ANNEX
SPECIFICATION FOR STRUCTURES TO BE BUILT IN DISASTER AREAS
CHAPTER I - GENERAL PRINCIPLES
1.1.
SCOPE
1.1.1 - Requirements of this Specification shall be applicable to newly constructedbuildings as well as to existing buildings.
1.1.2 - Provisions to be applied for the prevailing buildings of which the intended use
and / or carrier system shall be changed, the performance shall be evaluated before or after
the earthquake and buildings to be strengthened were given in Section - 7.
1.1.3 - Requirements of this Specification shall be applicable to reinforced concrete(cast-in-situ and pre - stressed or non - pre - stressed prefabricated) buildings, structuralsteel buildings and building-like structures, and timber, masonry and adobe buildings.
1.1.4 - Minimum conditions and rules to be implied to wooden buildings and such kindof buildings shall be determined by the Ministry of Public Works and Settlement until theprovisions of relevant specification shall be put into effect and projects of them shall bearranged according to those basis.
1.1.5 - In addition to buildings and building-like structures, non-building structures
permitted to be designed in accordance with the requirements of this Specification arelimited with those specified in 2.12 of Chapter 2. In this context bridges, dams, harbor
structures, tunnels, pipelines, power transmission lines, nuclear power plants, natural gas
storage facilities, underground structures and other structures designed with analysis andsafety rules that are different than those for buildings are outside the scope of thisSpecification.
1.1.6 - Buildings equipped with special system and equipment between foundation andsoil for the purpose of isolation of building structural system from the earthquake
motion, and buildings incorporating other active and passive control systems are out of
the scope of this Specification.
1.1.7 - Rules to be applied to structures which are outside the scope shall be
specifically determined by the Ministries supervising the constructions and such
structures shall be designed to those rules until their own special specifications areprepared.
The objective of this Part of the Specification is to define the minimum requirements
for the earthquake resistant design and construction of buildings and building-likeof structures or their parts subjected to earthquake ground motion.
1.2.
GENERAL PRINCIPLES
1.2.1 - The general principle of earthquake resistant design to this Specification is toprevent structural and non-structural elements of buildings from any damage in lowintensity earthquakes; to limit the damage in structural and non-structural elements torepairable levels in medium-intensity earthquakes, and to prevent the overall or partial
collapse of buildings in high-intensity earthquakes in order to avoid the loss of life.
Performance criteria based on the evaluation and reinforcement of the existing buildings
is stated in Chapter 7.

11.2.2 - The design earthquake considered in this Specification, corresponds to highintensity earthquake defined in 1.2.1 above. For buildings with Building Importance Factor
of I=1 in accordance with Chapter 2, Table 2.3, the probability of exceedance of thedesign earthquake within a period of 50 years is 10 %. Earthquakes with different theprobability of exceedance are defined in Chapter 7 in order to be considered in theevaluation and reinforcement of the existing buildings.
1.2.3 - Seismic zones cited in this Specification are the first, second, third and fourth
seismic zones depicted in Seismic Zoning Map of Turkey prepared by the Ministry of
Public Works and Settlement and issued by the decree of the Council of Ministers dated
18/04/1996 and numbered 96/8109.
1.2.4 - Buildings to be built in the seismic zones according to this Specification shall bein accordance with Turkish Standards and “General Technical Specification” of the
Ministry of Public Works and Settlement in terms of materials and labor.

2CHAPTER 2 - ANALYSIS REQUIREMENTS FOR EARTHQUAKERESISTANT BUILDINGS
2.0. NOTATION
A (T) = Spectral Acceleration CoefficientAo= Effective Ground Acceleration CoefficientBa= Design internal force component of a structural element in the direction of
its principal axis a
Bax= Internal force component of a structural element in the direction of its
principal axis a due to earthquake in x direction
Bay= Internal force component of a structural element in the direction of its
principal axis a due to earthquake in y direction perpendicular to x direction
Bb= Design internal force component of a structural element in the direction of
its principal axis b
Bbx= Internal force component of a structural element in the direction of its
principal axis b due to earthquake in x direction
Bby= Internal force component of a structural element in the direction of its
principal axis b due to earthquake in y direction perpendicular to x directionBB= Any size calculated with the combination of mode contributions in theMode-Superposition Method
BD= Amplified value of BBDi= Amplification factor to be applied in Equivalent Seismic Load Method to ±%5 additional eccentricity at i’th storey of a torsionally irregular building
dfi= Displacement calculated at i’th storey of building under fictitious loads Ffi
di= Displacement calculated at i’th storey of building under design seismic
loads
Ffi
= Fictitious load acting at i’th storey in the determination of fundamental
natural vibration period
Fi= Design seismic load acting at i’th storey in Equivalent Seismic Load Methodfe= Equivalent seismic load acting at the mass centre of the mechanical andelectrical equipmentg= Acceleration of gravity (9.81 m / s2)
gi= Total dead load at i’th storey of buildingHi= Height of i’th storey of building measured from the top foundation level (Inbuildings with rigid peripheral basement walls, height of i’th storey ofbuilding measured from the top of ground floor level)
HN= Total height of building measured from the top foundation level (Inbuildings with rigid peripheral basement walls, total height of building
measured from the top of the ground floor level)
Hw= Total height of partition measured from under the foundation or from theground floorhi= Height of i’th storey of building [m]I= Building Importance Factor= Length of partition or piece of strap partition on planw
Mn
= Modal mass of the n’th natural vibration mode
Mxn
= Effective participating mass of the n’th natural vibration mode of building in
the x earthquake direction consideredMyn= Effective participating mass of the n’th natural vibration mode of building in
the y earthquake direction consideredmi= i’th storey mass of building (mi = wi / g)
= In the case where floors are modeled as rigid diaphragms, mass moment ofmθiinertia around vertical axis passing through unshifted mass centre of i’thstorey of buildingN= Total number of stories of building from the foundation level (In buildings
with rigid peripheral basement walls, total number of stories from theground floor level)
3

n
qi
R

=
=
=
Rdown, Rup =

RNÇ

=

RYP

=

Ra(T) =
S(T)=
Sae(T) =SaR(Tr) =T=
T1=
TA ,TB =Tm , Tn =
Vi
=
Vt
=
VtB

=

W

=

we
wi

=
=

Y

=

α
αS

=
=

β

=

∆i
(∆i)ave∆FNδi(δi)mak
ηbi
ηci
ηki
Φxin

=
=
=
=
=
=
=
=
=

Φyin

=

Φθin

=

θi

=

Live Load Participation Factor
Total live load at i’th storey of building
Structural Behavior Factor
In case single storey frames with columns hinged at the top are used as top
floor (roof top) in cast – in – situ reinforced concrete, prefabricated andstructural steel buildings, R factors defined for lower stories and the top
floor, respectively.
Structural Behavior Factor defined in Table 2.5 for the case where entire
seismic loads are carried by frames of nominal ductility level
Structural Behavior Factor defined in Table 2.5 for the case where entire
seismic loads are carried by walls of high ductility level
Seismic Load Reduction Factor
Spectrum Coefficient
Elasticity spectrum ordinate [m /s2]
Acceleration spectrum ordinate for the r’th natural vibration mode [m /s2]
Building natural vibration period [s]First natural vibration period of building [s]Spectrum Characteristic Periods [s]m’th and n’th natural vibration periods of building [s]Storey shear at i’th storey of building in the earthquake direction considered
In the Equivalent Seismic Load Method, total equivalent seismic load acting
on the building (base shear) in the earthquake direction considered
In the Mode-Superposition Method, total design seismic load acting on thebuilding (base shear) obtained by modal combination in the earthquake
direction considered
Total weight of building calculated by considering Live Load Participation
Factor
Weight of mechanical or electrical equipment
Weight of i’th storey of building by considering Live Load Participation
FactorSufficient number of natural vibration modes taken into account in the ModeSuperposition Method
Coefficient used for determining the gap size of a seismic joint
Ratio of sum of shear forces developed at the bases of structural walls of highductility level to total shear force developed at the bases for the entire
building
Coefficient used to determine lower limits of response quantities calculated byMode-Superposition Method
Storey drift of i’th storey of building
Average storey drift of i’th storey of building
Additional equivalent seismic load acting on the N’th storey (top) of building
Effective storey drift of i’th storey of building
Maximum effective storey drift of i’th storey of building
Torsionally Irregularity Factor defined at i’th storey of building
Strength Irregularity Factor defined at i’th storey of building
Stiffness Irregularity Factor defined at i’th storey of building
In buildings with floors modeled as rigid diaphragms, horizontal componentof n’th mode shape in the x direction at i’th storey of building
In buildings with floors modeled as rigid diaphragms, horizontal componentof n’th mode shape in the y direction at i’th storey of building
In buildings with floors modeled as rigid diaphragms, rotational componentof n’th mode shape around the vertical axis at i’th storey of building
Second Order Effect Indicator defined at i’th storey of building

4

2.1. SCOPE
2.1.1 - Seismic loads and analysis requirements to be applied to the earthquake resistantdesign of all cast-in-site and prefabricated reinforced concrete buildings, structural steelbuildings and building-like structures to be built in seismic zones defined in 1.2.3 are
specified in this chapter. Rules for masonry buildings are specified in Chapter 5,
respectively.
2.1.2 - Rules for the analysis of building foundations and soil retaining structures are
specified in Chapter 6.
2.1.3 - Non-building structures which are permitted to be analyzed in accordance with therequirements of this chapter shall be limited to those given in Chapter.12.
2.1.4 – Design loads to be applied for strengthening and evaluating earthquake
performances of existing buildings are specified in Chapter 7.
2.2. GENERAL GUIDELINES AND RULES
2.2.1. General Guidelines for Building Structural Systems
2.2.1.1 – The building structural system resisting seismic loads as a whole as well as
each structural element of the system shall be provided with sufficient stiffness, stability
and strength to ensure an uninterrupted and safe transfer of seismic loads down to thefoundation soil.
2.2.1.2 - It is essential that floor systems possess sufficient stiffness and strength toensure the safe transfer of lateral seismic loads between the elements of the structural
system. In insufficient cases, appropriate transfer elements shall be arranged on floors.
2.2.1.3 - In order to dissipate a significant part of the seismic energy fed into thebuilding by ductile behavior of structural system, ductile design principles specified in
Chapter 3 and in Chapter 4 of this Specification should be followed.
2.2.1.4 - Design and construction of irregular buildings defined in 2.3.1 below should be
avoided. Structural system should be arranged symmetrical or nearly symmetrical inplan and torsional irregularity defined as type A1 irregularity in Table 2.1 should
preferably be avoided. In this respect, it is essential that stiff structural elements such as
structural walls should be placed so as to increase the torsional stiffness of the building.
On the other hand, vertical irregularities defined as types B1 and B2 in Table 2.1
leading to weak storey or soft storey at any storey should be avoided.
2.2.1.5 - Effects of rotations of column and in particular wall supporting foundations on
soils classified as group (C) and (D) in Table 6.1 of Chapter 6 should be taken into
account by appropriate methods of structural modeling.
2.2.2. General Rules for Seismic Loads
2.2.2.1 - Unless specified otherwise in this chapter, i n o r d e r t o d e t e r m i n eseismic loads acting on buildings, Spectral Acceleration Coefficient specified in 2.4
and Seismic Load Reduction Factor specified in 2.5 shall be based on.

5

2.2.2.2 - Unless specified otherwise in this Specification, seismic loads shall beassumed to act non-simultaneously along the two perpendicular axes of the building in thehorizontal plane. Provisions concerning combined effect of earthquakes in considered axes
are given in 2.7.5.
2.2.2.3 - Unless specified otherwise in this Specification, load factors to be used todetermine design internal forces under the combined effects of seismic loads and otherloads according to ultimate strength theory shall be taken from the relevant structural
specifications.
2.2.2.4 - It shall be assumed that the wind loads and seismic loads act nonsimultaneously, and the most unfavorable response quantity due to wind or earthquake
shall be considered for the design of each structural element. However, even if thequantities due to wind govern are more unfavorable, rules given in this Specification
shall be applied for dimensioning and detailing of structural elements and their joints.
2.3. IRREGULAR BUILDINGS
2.3.1. Definition of Irregular Buildings
Regarding the definition of irregular buildings whose design and construction should be
avoided because of their unfavorable seismic behavior, types of irregularities in planand in elevation are given in Table 2.1 and relevant conditions are given in 2.3.2 below.
2.3.2. Conditions for Irregular Buildings
Conditions related to irregularities defined in Table 2.1 are given below:
2.3.2.1 - Irregularity types A1 and B2 are irregularities that govern the selection of themethod of seismic analysis as specified in 2.6 below.
2.3.2.2 - In buildings with irregularity types A2 and A3, it shall be verified by
calculation in the first and second seismic zones that the floor systems are capable ofsafe transfer of seismic loads between vertical structural elements.
2.3.2.3 - In buildings with irregularity type B1, if total infill wall area at i’th storey isgreater than that of the storey immediately above, then infill walls shall not be taken
into account in the determination of ηci. In the range 0.60 ≤ (ηci) min < 0.80, structural
behavior factor given in Table 2.5 shall be multiplied by 1.25 (ηci)min and applied to theentire building in both earthquake directions. In no case, however, ηci < 0.60 shall bepermitted. Otherwise strength and stiffness of the weak storey shall be increased and theseismic analysis shall be repeated.
2.3.2.4 – In order to be applied in all seismic regions, conditions related to buildings withirregularity type B3 are specified below:(a) In all seismic zones, columns at any storey of the building shall in no case bepermitted to rest on the cantilever beams or on top of or at the tip of gussets provided in
the columns underneath.

6TABLE 2.1 - IRREGULAR BUILDINGSA – IRREGULARITIES IN PLAN
Related Items
A1 – Torsional Irregularity :The case where Torsional Irregularity Factor ηbi, which is defined forany of the two orthogonal earthquake directions as the ratio of the
2.3.2.1
maximum relative storey drift at any storey to the average relative
storey drift at the same storey in the same direction, is greater than 1.2(Figure 2.1). [ηbi = (∆i)max / (∆i)avr > 1.2]
Relative storey drifts shall be calculated in accordance with 2.7, byconsidering the effects of ± %5 additional eccentricities.
A2 – Floor Discontinuities :In any floor (Figure 2.2);
I - The case where the total area of the openings including those ofstairs and elevator shafts exceeds 1 / 3 of the gross floor area,
2.3.2.2
II – The case where local floor openings which make the safe transfer
of seismic loads difficult to vertical structural elements,
III – The cases of abrupt reductions in the in-plane stiffness andstrength of floors.
A3 – Projections in Plan :The cases where dimensions of projections in both of the two
perpendicular directions in plan exceed the total plan dimensions of
2.3.2.2
that storey of the building in the respective directions by more than
20% (Figure 2.3).
B – IRREGULARITIES IN ELEVATION
Related Items
B1 – Interstorey Strength Irregularity (Weak Storey) :In reinforced concrete buildings, the case where in each of theorthogonal earthquake directions, Strength Irregularity Factor ηciwhich is defined as the ratio of the effective shear area of any storey to
2.3.2.3
the effective shear area of the storey immediately above, is less than
0.80. [ηci = ( Ae)i / ( Ae)i+1 < 0.80]
Definition of effective shear area in any storey :Ae = Aw + Ag + 0.15 Ak (See 3.0 for notations)
B2 – Interstorey Stiffness Irregularity (Soft Storey) :The case where in each of the two orthogonal earthquake directions,
Stiffness Irregularity Factor ηki , which is defined as the ratio of theaverage relative storey drift at any i’th storey to the average relative
2.3.2.1
storey drift at the storey immediately above or below, is greater than
2.0. [ηki = (∆i / hi) avr / (∆i+1 / hi +1) avr > 2.0 orηki = (∆i / hi) avr / (∆i - 1 / hi -1) avr > 2.0]
Relative storey drifts shall be calculated in accordance with 2.7, byconsidering the effects of ± %5 additional eccentricities.
B3 - Discontinuity of Vertical Structural Elements :The cases where vertical structural elements (columns or structural
walls) are removed at some stories and supported by beams or
2.3.2.4
gusseted columns underneath, or the structural walls of upper stories
are supported by columns or beams underneath (Figure 2.4).

7(∆i)max(∆i)mini +1’st storey
floor

Earthquake
Directioni’ th storey
Floor

In the case where floors behave as rigid diaphragms
In their own planes:(∆i)ort = 1/2 [(∆i)max + (∆i)min]
Torsional irregularity factor :ηbi = (∆i)max / (∆i)ort
Torsional irregularity : ηbi > 1.2

Figure 2.1

Ab

Ab1

Type A2 irregularity - I
Ab / A > 1/3
Ab : Total area of openings
A : Gross floor area

Ab2

Ab = Ab1 + Ab2

AA

Type A2 irregularity - II
Section A - A
Type A2 irregularity - II and II

Figure2.2

8

ay
Ly

Ly
ay

ay
ax

Ly

ax

Lx

ax

ay
ax

Lx

ax
Lx

Type A3 irregularity:ax > 0.2 Lx and at the same time ay> 0.2 Ly

Figure 2.3

Bkz. 2.3.2.4 (a)Bkz. 2.3.2.4 (b)Bkz. 2.3.2.4 (c)Bkz. 2.3.2.4 (d))LJXUH2.4(b) In the case where a column rests on a beam which is supported at both ends,
all internal force components induced by the combined effect of vertical loads andseismic loads shall be increased by 50 % at all sections of the beam and at all
sections of the other beams and columns adjoining to the beam in the earthquake
direction considered.
(c) Structural walls at upper stories shall in no case be permitted to rest on the columns
below.
(d) Structural walls shall in no case be permitted in their own plane to rest on the beamspan at any storey of the building.

99

2.4. DEFINITION OF ELASTIC SEISMIC LOADS: SPECTRAL ACCELERATION
COEFFICIENTThe Spectral Acceleration Coefficient, A (T), which shall be considered as the basis forthe determination of seismic loads is given by Equation (2.1). Elastic Spectral
Acceleration, Sae (T) which is the ordinate of Elastic Acceleration Spectrum defined for 5% damped rate is derived by multiplying Spectral Acceleration Coefficient with gravity,g.
A (T) = Ao I S (T)(2.1)
Sae (T) = A (T) g
2.4.1. Effective Ground Acceleration Coefficient
The Effective Ground Acceleration Coefficient, Ao, appearing in Equation (2.1) is
specified in Table 2. 2.
TABLE 2.2 - EFFECTIVE GROUND ACCELERATION COEFFICIENT (Ao)Seismic Zone
Ao
1
0.40
2
0.30
3
0.20
4
0.10
2.4.2. Building Importance Factor
The Building Importance Factor, I, appearing in Equation (2.1) is specified in Table
2.3.
TABLE 2.3 - BUILDING IMPORTANCE FACTOR (I)Purpose of Occupancy or Typeof Building
1. Buildings required to be utilized after the earthquake andbuildings containing hazardous materialsa) Buildings required to be utilized immediately after the earthquake(Hospitals, dispensaries, health wards, fire fighting buildings andfacilities, PTT and other telecommunication facilities, transportation
stations and terminals, power generation and distribution facilities;
governorate, county and municipality administration buildings, firstaid and emergency planning stations)b) Buildings containing or storing toxic, explosive and flammablematerials, etc.
2. Intensively and long-term occupied buildings andbuildings preserving valuable goodsa) Schools, other educational buildings and facilities, dormitories andhostels, military barracks, prisons, etc.
b) Museums
3. Intensively but short-term occupied buildings
Sport facilities, cinema, theatre and concert halls, etc.
4. Other buildings
Buildings other than above defined buildings. (Residential and officebuildings, hotels, building-like industrial structures, etc.)

Importance
Factor (I)

1.5

1.4

1.2
1.0

10

2.4.3. Spectrum Coefficient
2.4.3.1 - The Spectrum Coefficient, S(T), appearing in Equation (2.1) shall be
determined by Equation (2.2), depending on the local site conditions and thebuilding natural period, T (Figure 2.5):
T
S (T ) = 1 + 1.5(0 ≤ T ≤ TA )TA
(2.2)
S (T ) = 2.5(TA < T ≤ TB )0.8
TS (T ) = 2.5 B(TB < T )T
Spectrum Characteristic Periods, TA and TB , appearing in Equation (2.2) are
specified in Table 2.4, depending on Local Site Classes defined in Table 6.2 of Chapter
6.
TABLE 2.4 - SPECTRUM CHARACTERISTIC PERIODS (TA, TB)
Local Site Class
according to Table 6.2
Z1
Z2
Z3
Z4

TA
(second)
0.10
0.15
0.15
0.20

TB
(second)
0.30
0.40
0.60
0.90

2.4.3.2 - In case where the requirements specified in 6.2.1.2 and 6.2.1.3 of Chapter
6 are not met, spectrum characteristic periods defined in Table 2.4 for local site class
Z4 shall be used.
2.4.4. Special Design Acceleration Spectra
In required cases, elastic acceleration spectrum may be determined through special
investigations by considering local seismic and site conditions. However spectral
acceleration coefficients corresponding to so obtained acceleration spectrum ordinates
shall in no case be less than those determined by Equation (2.1) based on
relevant characteristic periods specified in Table 2.4.
S(T)2.5
S(T) = 2. 5 (TB / T)

0. 8

1.0

TA

TB
Figure 2.5

112.5. REDUCTION OF ELASTIC SEISMIC LOADS: SEISMIC LOAD
REDUCTION FACTOR
In order to consider the specific nonlinear behavior of the structural system during
earthquake, elastic seismic loads to be determined in terms of spectral acceleration
coefficient defined in 2.4 shall be divided to below defined Seismic Load Reduction
Factor to account for. Seismic Load Reduction Factor, shall be determined by
Equation (2.3) in terms of Structural System Behavior Factor, R, defined in Table
2.5 for various structural systems, and the natural vibration period T.
T
Ra (T ) = 1.5 + (R − 1.5)
(0 ≤ T ≤ TA )(2.3)
TA
Ra (T ) = R(TA < T )2.5.1. General Conditions on Ductility Levels of Structural Systems

2.5.1.1 - Definitions of and requirements to be fulfilled for structural systems of highductility level and structural systems of nominal ductility level whose Structural
System Behavior Factors are given in Table 2.5, are given in Chapter 3 forreinforced concrete buildings and in Chapter 4 for structural steel buildings.
2.5.1.2 - In structural systems denoted as being high ductility level in Table 2.5,
ductility levels shall be high in both lateral earthquake directions. Systems whichhave high or combined ductility level in one earthquake direction and nominal
ductility level in the perpendicular earthquake direction shall be deemed to be structural
systems of nominal ductility level in both directions.
2.5.1.3 – Systems which have the same ductility level in both directions or high in one
direction and mixed in other direction, different R coefficients can be used in different
directions.
2.5.1.4 – Bare or infilled joist and waffle slab systems whose columns and beams do notsatisfy the requirements given in 3.3, 3.4 and 3.5, and reinforced concrete flat slab
systems without structural walls shall be treated as systems of nominal ductility level.
2.5.1.5 – In the first and second seismic zones;(a) Except paragraph (b) below, structural systems of high ductility level shall be used forthe reinforced concrete buildings with structural systems comprised of frames only.
(b) In reinforced concrete buildings with Building Importance Factor I = 1.2 and I = 1.0
according to the Table 2.3, structural systems comprised of frames of nominal ductility
level can only be built on the condition that HN ≤ 16 m.
(c) In all buildings with Building Importance Factor of I = 1.5 and I = 1.4 according toTable 2.3, structural systems of high ductility level or structural systems with mixed
ductility level defined in 2.5.4.1 shall be used.
2.5.1.6 – Structural systems of nominal ductility level without structural walls can only bepermitted to be built in the third and fourth seismic zones with the following conditions:(a) Reinforced concrete buildings defined in 2.5.1.4, can be built on the condition that
HN ≤ 13 m.

12(b) – Excluding the systems indicated in 2.5.1.4, reinforced concrete and structuralsteel buildings comprised only of frames of nominal ductility level are permitted to bebuilt on the condition that HN ≤ 25 m.
TABLE 2.5 - STRUCTURAL SYSTEM BEHAVIOUR FACTORS (R)
Systems of Systems ofNominalHigh
BUILDING STRUCTURAL SYSTEM
Ductility
Ductility
Level
Level
(1) CAST-IN-SITE REINFORCED CONCRETE
BUILDINGS(1.1) Buildings in which seismic loads are fully resisted byframes................................................................................
48(1.2) Buildings in which seismic loads are fully resisted bycoupled structural walls......................................................
47(1.3) Buildings in which seismic loads are fully resisted bysolid structural walls...........................................................
46(1.4) Buildings in which seismic loads are jointly resisted
by frames and solid and / or coupled structural walls............
4
7(2) PREFABRICATED REINFORCED CONCRETE
BUILDINGS(2.1) Buildings in which seismic loads are fully resisted byframes with connections capable of cyclic moment transfer
37(2.2) Single-storey buildings in which seismic loads are
fully resisted by columns with hinged upper connections
3(2.3) Prefabricated buildings with hinged frame connections
in which seismic loads are fully resisted by prefabricated orcast – in – situ solid structural walls and / or coupled5
structural walls.
(2.4) Buildings in which seismic loads are jointly resisted
by frames with connections capable of cyclic momenttransfer and cast-in-situ solid and / or coupled structural
3
6
walls
(3) STRUCTURAL STEEL BUILDINGS(3.1) Buildings in which seismic loads are fully resisted byframes.................................................................................
58(3.2) Single – storey buildings in which seismic loads are
fully resisted by columns with connections hinged at the
top…..…………………………………………………….
4(3.3) Buildings in which seismic loads are fully resisted bybraced frames or cast-in-situ reinforced concrete structural
walls(a) Centrically braced frames ……………..................
54(b) Eccentrically braced frames …………………………
7(c) Reinforced concrete structural walls.............................
64(3.4) Buildings in which seismic loads are jointly resisted
by structural steel braced frames or cast-in-situ
reinforced concrete structural walls(a) Centrically braced frames....................................... (b)5
6
Eccentrically braced frames......................................... (c)8Reinforced concrete structural walls.............................
74

13

2.5.2. Conditions for Reinforced Concrete Solid Structural Wall - Frame Systems ofHigh Ductility Level
Requirements for buildings where seismic loads are jointly resisted by reinforced
concrete solid structural walls of high ductility level and reinforced concrete or
structural steel frames of high ductility level are given below:

2.5.2.1 – In order to use R = 7 for cast – in – situ reinforced concrete and structural steel
frame systems or R = 6 for prefabricated reinforced concrete frame systems as it is given
in Table 2.5, sum of shear forces developed at the bases of solid structural walls underseismic loads shall not exceed 75% of the total shear force developed at the bases for theentire building (αS ≤ 0.75).
2.5.2.2 – In the case where the requirement 2.5.2.1 cannot be satisfied, coefficient R to
be used in the range 0.75 < αS ≤ 1.0 shall be calculated by the expression R = 10 − 4 αS forcast – in – situ reinforced concrete and structural steel frame systems and by R = 9 − 4 αSfor prefabricated reinforced concrete frame systems.
2.5.2.3 – In structural walls in which Hw / w ≤ 2.0, internal forces calculated according to
R coefficients defined above shall be increased by being multiplied with [3 / (1 + Hw /w)]. However, this coefficient is not taken more than 2.
2.5.3. Conditions on Mandatory Use of Structural Walls in Certain Systems ofNominal Ductility Level
Systems of nominal ductility level defined in paragraphs (a) and (b) of 2.5.1.6 can be built
in all seismic regions and over the height limit defined in the same paragraphs. But in thiscase, it is mandatory to use solid or coupled reinforced concrete structural walls of
nominal or high ductility level in reinforced concrete buildings through the full height ofthe building with the following conditions fulfilled and centrically or eccentrically braced
frames of nominal or high ductility level in structural steel buildings.

2.5.3.1 – When structural walls of nominal ductility level are used in the structural
system, sum of shear forces developed at the bases of structural walls according toseismic loads shall be more than 75% of the total shear force developed for theentire building in each earthquake direction.
2.5.3.2 When structural walls of high ductility level are used in the structural
system, requirements specified in 2.5.4.1 below for mixed structural systems shall beapplied.
2.5.4. Conditions for Mixed Structural Systems in Terms of Ductility Level
2.5.4.1 – Systems of nominal ductility level defined in paragraphs (a) and (b) of 2.5.1.6
are permitted to be mixed with structural walls ofhigh ductility level. In so
obtained systems of mixed ductility level, solid or coupled reinforced concrete structural
walls of high ductility or for steel buildings structural steel eccentric or centric braced
frames may be used provided that the following conditions are met.

14

(a) In the seismic analysis of such mixed systems, frames and structural walls (orbraced frames) shall be jointly considered, however in each earthquake direction it
shall be αS ≥ 0.40.
(b) In the case where αS ≥ 2/3 in both earthquake directions, R factor defined in Table
2.5 for the case where seismic loads are fully resisted by structural of high ductility
level (R = RYP), may be used for the entire structural system.
(c) In the range 0.40 < αS < 2/3, the expression R = RNÇ + 1.5 αS (RYP − RNÇ) shall beapplied to the entire structural system in both earthquake directions.
2.5.4.2 – Reinforced concrete rigid peripheral walls used in basements of buildings shallnot be taken into consideration as parts of structural wall systems or structural wallframe systems appearing in Table 2.5. Rules to be applied in analysis of such buildings
are given in 2.7.2.4 and 2.8.3.2.
2.5.5. Conditions for Systems with Hinged Connections
2.5.5.1 – In reinforced concrete buildings made of single – storey frames with columns
hinged at the top;(a) In case cast – in – situ reinforced concrete columns are used, R factor defined in item(2.2) of Table 2.5 shall be used for prefabricated buildings.
(b) Conditions concerning reinforced concrete prefabricated and structural steel buildings,
whose R factors are given in items (2.2) and (3.2) of Table 2.5, are given in 2.5.5.2.
Conditions relating to usage of such frames as top floor (roof top) in cast – in – situ
reinforced concrete, prefabricated and structural steel buildings are defined in 2.5.5.3.
2.5.5.2 – A single mezzanine floor can be constructed inside such buildings provided that
it is not larger than 25 % of place area of the building. Structural system of mezzanine
floor shall be taken into account in the seismic analysis of such buildings together
with the main structural frames. In this case, combined system shall be arranged as thesystem of high ductility level in prefabricated reinforced concrete buildings. In combined
system, existence of torsional irregularity shall be controlled and if it exists, it shall betaken into account in analysis. Connections of mezzanine floor with main structural
frames can be hinged or monolithic.
2.5.5.3 – In case single storey frames with columns hinged at the top are used as top floor(roof top) in cast – in – situ reinforced concrete, prefabricated and structural steelbuildings, for the top floor, R factor (Rup) defined in items (2.2) or (3.2) of Table 2.5 andfor the lower floors, R factor (Rdown) which may be defined differently shall be used with
together provided that following conditions are met.
(a) At the beginning, seismic analysis shall be made for entire building according to 2.7 or
2.8 by taking R = Rdown. Reduced and effective relative storey drifts defined in 2.10.1 shallbe obtained for entire building from this analysis.
(b) Internal forces of the top floor shall be obtained by multiplying internal forces
calculated in (a) with (Rdown / Rup) ratio.
(c) On the other hand, internal forces of lower floors shall be composed of sum of twosides. First side is the internal forces calculated in (a). Second side shall be calculated byacting structural system of lower floors by multiplying the forces calculated in (b) as
support reactions of top floor columns with (1 – Rup / Rdown).

15

2.6. SELECTION OF ANALYSIS METHOD
2.6.1. Analysis Methods
Methods to be used for the seismic analysis of buildings and building-like structuresare, Equivalent Seismic Load Method given in 2.7, Mode – Superposition Method given
in 2.8 and Analysis Methods in the Time Domain given in 2.9. Methods given in 2.8 and2.9 may be used for the seismic analysis of all buildings and building-like structures.

2.6.2. Application Limits of Equivalent Seismic Load Method
Buildings for which Equivalent Seismic Load Method given in 2.7 is applicable aresummarized in Table 2.6. Methods given in 2.8 or 2.9 shall be used for the seismic
analysis of buildings outside the scope of Table 2.6.

TABLE 2.6 - BUILDINGS FOR WHICH EQUIVALENT SEISMIC LOAD
METHOD IS APPLICABLE
Total Height
Seismic
Type of Building
Zone
Limit
Buildings in which torsional irregularity coefficient1, 2
HN ≤ 25 m
satisfies the condition ηbi ≤ 2.0 at every storey
Buildings in which torsional irregularity coefficient
1, 2
satisfies the condition ηbi ≤ 2.0 at every storey and at HN ≤ 40 m
the same time without type B2 irregularity
All buildings
3, 4
HN ≤ 40 m
2.7. EQUIVALENT SEISMIC LOAD METHOD
2.7.1. Determination of Total Equivalent Seismic Load
2.7.1.1 – Total Equivalent Seismic Load (base shear), Vt, acting on the entire building in
the earthquake direction considered shall be determined by Equation (2.4).
WA(T1 )
≥ 0.10 Ao I W
(2.4)
Vt =
Ra (T1 )The first natural vibration period of the building, T1, shall be calculated in accordancewith 2.7.4.
2.7.1.2 – Total building weight, W, to be used in Equation (2.4) as the seismic weight
shall be determined by Equation (2.5).

W=

N

i =1

wi

(2.5)

Storey weights wi of Equation (2.5) shall be calculated by Equation (2.6).
w i = gi + n q i(2.6)
Live Load Participation Factor, n, appearing in Equation (2.6) is given in Table 2.7. In
industrial buildings, n = 1 shall be taken for fixed equipment weights while crane
payloads shall not be taken into account in the calculation of storey weights 30 % ofsnow loads shall be considered in calculation of weight of roof top to be used indetermination of seismic loads.

16

TABLE 2.7 - LIVE LOAD PARTICIPATION FACTOR (n)Purpose of Occupancy of Building
Depot, warehouse, etc.
School, dormitory, sport facility, cinema, theatre, concert hall, car park,
restaurant, shop, etc.
Residence, office, hotel, hospital, etc.

n
0.80
0.60
0.30

2.7.2. Determination of Design Seismic Loads Acting at Storey Levels
2.7.2.1 – Total equivalent seismic load determined by Equation (2.4) is expressed by
Equation (2.7) as the sum of equivalent seismic loads acting at storey levels (Fig. 2.6a):

Vt = ∆FN +

N
i=1

Fi

(2.7)

2.7.2.2 – Additional equivalent seismic load, ∆FN, acting at the N’th storey (top) of thebuilding shall be determined by Equation (2.8).
∆FN = 0.0075 N Vt

(2.8)

2.7.2.3 – Excluding ∆FN , remaining part of the total equivalent seismic load shall be
distributed to stories of the building (including N’th storey) in accordance with
Equation (2.9).
wH
Fi = (Vt − ∆FN ) N i i(2.9)
wj H jj=1

2.7.2.4 – In buildings with reinforced concrete peripheral walls at their basements being
very rigid relative to upper stories and basement floors behaving as rigid diaphragms inhorizontal planes, equivalent seismic loads acting on the basement stories and on theupper stories shall be calculated independently as in the following. These loads shall beapplied together with structural system composed of combination of upper and lower
stories.
(a) In determining the total equivalent seismic load and equivalent storey seismic loads
in accordance with 2.7.1.1, 2.7.2.2 and 2.7.2.3, appropriate R factor shall be selectedfrom Table 2.5 without considering the rigid peripheral basement walls and seismic
weights of the upper stories only shall be taken into account. In this case, foundation top
level appearing in the relevant definitions and expressions shall be replaced by theground floor level. Fictitious loads used for the calculation of the first natural vibration
period in accordance with 2.7.4.1 shall also be based on seismic weights of the upper
stories only (Fig. 2.6b).
(b) In calculating equivalent seismic loads acting on rigid basement stories, seismic
weights of basements only shall be taken into account and Spectrum Coefficient
shall be taken as S (T) = 1. In determining equivalent seismic loads acting on eachbasement storey, spectral acceleration obtained from Equation (2.1) shall be multiplied
directly with the respective weight of the storey and resulting elastic loads shall be
reduced by dividing them to Ra (T) = 1.5 (Fig. 2.6c).
(c) Strength of flooring system of ground storey, in its self – plane, surrounded by multi
rigid walls and located at the passage from upper stories to sub – basement shall becontrolled according to internal forces obtained in this analysis.

17

FN + ∆FN

FN + ∆FN

wN

wN

Fi

wi
HN

Fi

wi

w2

Hi

HN
w1
Vt
w2

Hi
Fbk

wbk

w1
Fbk = Ao I wbk / 1.5
Vt
(a)

(b)

(c)

Figure 2.6
2.7.3. Displacement Components to be Considered and Application Points ofSeismic Loads
2.7.3.1 – In buildings where floors behave as rigid horizontal diaphragms, two lateraldisplacement components and the rotation around the vertical axis shall be taken into
account at each floor as independent static displacement components. In order toconsider eccentricity effect, at each floor, equivalent seismic loads determined inaccordance with 2.7.2 shall be applied on the points obtained by shifting the actual
mass centre by + 5% and − 5% times the floor length in the perpendicular direction to theearthquake direction considered as well as to storey mass center (Fig. 2.7).
2.7.3.2 - In buildings where type A2 irregularity (defined in Table 2.1) exists and floors
do not behave as rigid horizontal diaphragms, sufficient number of independent static
displacement components shall be considered to account for the in-plane
deformation of floors. In order to consider additional eccentricity effects, eachof the individual masses distributed over each floor shall be shifted by + 5% and − 5%times the floor length in perpendicular direction to the earthquake direction considered(Fig. 2.8).
2.7.3.3 - In the case where type A1 irregularity defined in Table 2.1 exists at any i’thstorey such that the condition 1.2 < ηbi ≤ 2.0 is satisfied, ± 5% additional eccentricity
applied to this floor according to 2.7.3.1 and / or 2.7.3.2 shall be amplified by multiplying
with coefficient Di given by Equation (2.10) for both earthquake directions.
η 
Di =  bi  1.2 2

(2.10)

18

Bxey
x earthquake
Direction

By
ey

ex

ey = 0.05By

exex = 0.05Bx
y Earthquake
direction

Figure 2.7
Bx

ejx ejx
ejx = 0.05Bx

Figure 2.8
2.7.4. Determination of First Natural Vibration Period of Building
2.7.4.1 – In the case Equivalent Seismic Load Method is applied, the first natural
vibration period of building in the direction of earthquake is not taken more than thevalue calculated by Equation (2.11).
1/ 2

 N
2 
∑ mi d fi 
 i=1
T1 = 2π  N ∑ Ffi d fi 
 i=1
(2.11)

Ffi referring to the fictitious load acting on the i’th storey shall be obtained from
Equation(6.9) by substituting any value (for example unit value) in place of (Vt − ∆FN)
(Figure 2.9).
2.7.4.2 – In buildings in which N > 13 excluding basement(s), natural period is not taken
more than 0.1 N as being independent from the value calculated in Equation (2.11).

19

wN

Ffi =

wi H iNwi

Ffi∑ wj H j

dfi

j=1

Hi

Figure 2.9
2.7.5. Internal Forces in the Directions of Elements at Principal Axis
Under combined effect of the earthquakes in the directions of x and y acting on structural
system respectively, internal forces in the directions of principal axes a and b of elementsof structural system shall be obtained by Equation (2.12) so as to yield the mostunfavorable results (Figure 2.10).
Ba = ± Bax ± 0.30 Bay

veya Ba = ± 0.30 Bax ± Bay

Bb = ± Bbx ± 0.30 Bby

veya Bb = ± 0.30 Bbx ± Bby(2.12)bx earthquake
direction

b a
b a

a

a

a

b
a

a

b

a

b

b

y

b
y earthquake
directionx

Figure 2.10
2.8. MODE SUPERPOSITION METHOD
In this method, maximum internal forces and displacements are determined by
the statistical combination of maximum contributions obtained from each of thesufficient number of natural vibration modes considered.
2.8.1. Acceleration Spectrum
Reduced acceleration spectrum ordinate to be taken into account in any n’th
vibration mode shall be determined by Equation (2.13).

20

Sae (Tn )(2.13)Ra (Tn )In the case where elastic design acceleration spectrum is determined through special
investigations in accordance with 2.4.4, relevant spectrum ordinate shall be considered in
Equation (2.13) in lieu of Sae(Tn).

SaR (Tn ) =2.8.2. Dynamic Degrees of Freedom to be considered
2.8.2.1 – In buildings where floors behave as rigid horizontal diaphragms, twohorizontal degrees of freedom in perpendicular directions and a rotational degree of
freedom with respect to the vertical axis passing through the mass center shall beconsidered at each storey. Modal seismic loads shall be calculated for those degrees of
freedom at each storey, but in order to consider additional eccentricity effects, they shallbe applied to the points obtained by shifting the actual mass center b y +5 % and −5 %of the floor length in perpendicular direction to the earthquake direction and to themass center as an additional load (Figure 2.7).
2.8.2.2 – In buildings where floor discontinuities defined under the title of A2
irregularity exists and floors do not behave as rigid horizontal diaphragms, sufficientnumber of dynamic degrees of freedom shall be considered to account for the inplane deformation of floors. In order to consider additional eccentricity effects, each of
the modal seismic loads acting on the individual masses distributed over each floor
shall be shifted by +5 % and −5 % of the floor length in perpendicular direction to theearthquake direction (Fig. 2 . 8 ). In such buildings, internal force and displacement
quantities due to additional eccentricity effects alone may also be calculated inaccordance with 2.7. Such quantities shall be directly added to those combined inaccordance with below given 2.8.4 without taking into account additional eccentricity
effects.
2.8.3. Sufficient Number of Vibration Modes to be considered
2.8.3.1 - Sufficient number of vibration modes, Y, to be taken into account in theanalysis shall be determined to the criterion that the sum of effective participating
masses calculated for each mode in each of the given x and y lateral earthquake
directions perpendicular to each other shall in no case be less than 90 % of the totalbuilding mass.
Y
Y L2
N
xn
≥ 0.90 mi
M xn =
n=1
n=1 M ni=1
Y
n=1

M yn =

Y

2
Lyn

n=1

Mn

≥ 0.90(2.14)N
i=1

mi

The expressions of Lxn, Lyn and modal mass Mn appearing in Equation (2.14) are given
below for buildings where floors behave as rigid diaphragms:

Lxn =

N
i=1

Mn =

mi

N
i=1

(mi

xin

;

2
xin + mi

Lyn =

N

mi

yin

2
yin + mθi

2
θin )

i=1

(2.15)

21

2.8.3.2 - In analysis of buildings with reinforced concrete peripheral walls at theirbasements being very rigid relative to upper stories and basement floors behaving as rigid
diaphragms in horizontal planes, it may be sufficed with the consideration of vibration
modes which are effective in the upper stories only. In this case, in the analysis performed by
the Mode Superposition Method which corresponds to the analysis by Equivalent Seismic
Load Method as given in Paragraph (a) of 2.7.2.4, the coefficient R selected from Table
2.5 shall be used without considering the rigid peripheral basement walls whereas theupper storey masses only shall be taken into account. Paragraphs (b) and (c) of 2.7.2.4 shallbe applied as they are given.
2.8.4. Combination of Modal Contributions
Rules to be applied for the statistical combination of non-simultaneous maximum
contributions of response quantities calculated for each vibration mode, such as base shear,storey shear, internal force components, displacement and storey drift, are specified in
the following provided that they are applied independently for each response
quantity:

2.8.4.1 – In the cases where natural periods of any two vibration mode with Tm < Tnalways satisfy the condition Tm / Tn < 0.80, Square Root of Sum of Squares (SRSS) Rule
may be applied for the combination of maximum modal contributions.
2.8.4.2 - In the cases where the above given condition is not satisfied, Complete
Quadratic Combination (CQC) Rule shall be applied for the combination of maximum
modal contributions. In the calculation of cross correlation coefficients to be used in
the application of the rule, modal damping factors shall be taken as 5 % for all modes.
2.8.5. Lower Limits of Response Quantities
In the case where the ratio of the base shear in the given earthquake direction, VtB ,which is obtained through modal combination according to 2.8.4, to the base shear, Vt ,obtained by Equivalent Seismic Load Method through Equation 2.4 is less than the
below given value of β (VtB < β Vt), all internal force and displacement quantities
determined by Mode Superposition Method shall be amplified in accordance with
Equation (2.16).
BD =

β Vt
BB
VtB

(2.16)In the case where at least one of the irregularities of type A1, B2 or B3 defined inTable 2.1 exists in a building β= 0.90, whereas none of them exists β= 0.80 shall be
used in Equation (2.16).

2.8.6. Internal Forces in the Directions of Elements at Principal Axis
Under combined effect of the earthquakes in the directions of x and y acting on structural
system respectively, directional combination rule given in 2.7.5 shall be applied to theinternal forces obtained by combining elements of structural system in accordance with
2.8.4 and in the direction of a and b principal axes.

222.9. ANALYSIS METHODS IN TIME DOMAIN
Artificially generated, previously recorded or simulated ground motions may be used forthe linear or nonlinear elastic analysis of buildings and building-like structures in the time
domain.

2.9.1. Artificially Generated Seismic Ground Motions
In order to use artificially generated ground motions, at least three seismic ground motions
shall be generated in accordance with the following properties.
(a) The duration of strong motion part of the acceleration shall neither be less than 5times o f the first natural vibration period of the building nor less than 15 seconds.
(b) Average of spectral acceleration values of simulated seismic ground motion
corresponding to period zero shall not be less than A o g.
(c) Average of spectral acceleration values to be recalculated for each simulated
acceleration record with 5 % damping ratio shall not be less than 90 % of elastic spectral
accelerations Sae(T) defined in 2.4 for the periods between 0.2T1 and 2T1 according to first
period T1 in the direction of earthquakes considered. In the case where nonlinear elastic
analysis is performed in the time domain, spectral acceleration values to be based on inorder to obtain reduced seismic ground motion shall be calculated by Equation (2.13).
2.9.2. Recorded or Simulated Seismic Ground Motions
Recorded earthquakes or physically simulated ground motions to source and wave
propagation characteristics may be used. While generating such ground motions, floor
conditions should be taken into account concordantly. In case of using recorded or
simulated seismic ground motions at least three seismic ground motions shall be generated
and those motions shall satisfy all the conditions given in 2.9.1.

2.9.3. Analysis in Time Domain
In case of making nonlinear elastic analysis in time domain, internal force – transformationcohesions representing dynamic behavior of elements of structural system under cycling
loads shall be defined by utilizing related literature provided that their theoretical andexperimental validities are proven. In linear and nonlinear analysis, in case of using threeground motions the maximum of results, and in case of using at least seven groundmotions average of results shall be taken for the design.

2.10. LIMITATION OF RELATIVE STOREY DRIFTS, SECOND ORDER
EFFECTS AND SEISMIC JOINTS
2.10.1. Calculation and Limitation of Effective Relative Storey Drifts
2.10.1.1 – Reduced relative storey drift, ∆i, of any column or structural wall shall be
determined by Equation (2.17) as the difference of displacements between the twoconsecutive stories.
∆i = di − di − 1(2.17)

23

In Equation (2.17) di and di − 1 represent lateral displacements obtained from the analysis
according to reduced seismic loads at the ends of any column or structural wall at stories iand (i - 1). However, the condition in 2.7.4.2 and the condition of minimum equivalent
seismic load defined in Equation (2.4) may not be considered in calculation of di and ∆i.

2.10.1.2 – Effective relative storey drift, i, for columns and structural walls of the i’thstorey of a building for each earthquake direction shall be obtained from Equation (2.18).
(2.18)
δi = R ∆ i
2.10.1.3 – The maximum value of effective relative storey drifts, i, within a storey,( i)max, calculated by Equation (2.18) for columns and structural walls of the i’th storey of abuilding for each earthquake direction shall satisfy the condition given by Equation (2.19):(δi ) max
(2.19)≤ 0.02hi
This limit can be increased maximum of 50 % in single – storey buildings in which seismic
loads are fully resisted by structural steel frames with connections capable of cyclic momenttransfer.
2.10.1.4 – In the case where the condition specified by Equation (2.19) is not satisfied atany storey, the earthquake analysis shall be repeated by increasing the stiffness of thestructural system. The serviceability of nonstructural brittle elements (such as facadeelements) under effective relative storey drifts shall be verified by calculation even if theabove given conditions satisfied.
2.10.2. Second – Order Effects
Unless a more refined analysis considering the nonlinear elastic behavior of structural
system is performed, second-order effects may be taken into account as follows.

2.10.2.1 – In the case where Second – Order Effect Indicator, θi, satisfies the condition
given by Equation (2.20) for the earthquake direction considered at each storey, second –order effects shall be evaluated in accordance with currently enforced specifications ofreinforced concrete or structural steel design.

θi =(∆i )avr

N
j =i

wj

≤ 0.12(2.20)
Vi hi
Here (∆i)avr shall be determined in accordance with 2.10.1.1 as the average value of
reduced relative storey drifts calculated for i’th storey columns and structural walls within
the storey.
2.10.2.2 – In the case where the condition given by Equation (2.20) is not satisfied,seismic analysis shall be repeated by sufficiently increasing the stiffness of thestructural system.
2.10.3. Seismic Joints
Excluding the effects of differential settlements and rotations of foundations and theeffects of temperature change, the conditions are indicated concerning sizes of gaps to beretained in the seismic joints between building blocks or between the old and newly
constructed buildings:

24

2.10.3.1 - Unless a more unfavorable value is obtained in accordance with 2.10.3.2 below,
sizes of gaps shall not be less than the value found as result of multiplication of coefficient α
specified below with square root of sum of squares of displacements obtained in adjacentbuildings or blocks for each storey. Storey displacements to be considered shall be theaverage values of reduced displacements di calculated within a storey at the column or
structural wall joints. In case the seismic analysis is not possible for the existing old building,the storey displacements of old building shall not be assumed to be less than those obtained forthe new building at the same stories.
(a) α = R / 4 if all floor levels of adjacent buildings or building blocks are the same at all
stories.
(b) α = R / 2 shall be valid for entire building i f any of the floor levels of adjacentbuildings or building blocks are not the same.
2.10.3.2 – Minimum size of gaps shall be at least 30 mm up to 6 m height and fromthereon a minimum 10 mm shall be added for each 3 m height increment.
2.10.3.3 - Seismic joints shall be arranged so as to allow the independent movementof building blocks in all earthquake directions.
2.11. SEISMIC LOADS APPLIED TO STRUCTURAL
ARCHITECTURALELEMENTS,MECHANICALAND
EQUIPMENTAPPENDAGES,ELECTRICAL

2.11.1 – Equivalent seismic loads to be applied to structural appendages which areconnected to structural system but serving independently such as balconies, parapets,
chimneys, etc. and to all non – structural architectural elements such as facade andpartition panels, etc.; to be used in analysis of mechanical and electrical equipments andalso connections of these to structural system of building are given by Equation (2.21).
H(2.21)
f e = 0.5 Ao I we 1 + 2 i
HN
The seismic load calculated shall be acted to center of gravity of related element so as togive the most unfavorable internal forces in the horizontal direction. Half of equivalent
seismic load calculated in Equation (2.21) shall be acted vertically to the elements which
are not in the vertical direction.
2.11.2 – In the case where the sum of weights of mechanical or electrical equipment
indicated by we in Equation (2.21) at any i’th storey is greater than 0.2wi, equipment
weights and stiffness properties of their connections shall be taken into account in the
structural analysis.
2.11.3 – Equation(2.21) may not be applied in industrial buildings where floor
acceleration spectrum is determined by appropriate methods defining the peakacceleration at the floor where mechanical or electrical equipment are located.
2 . 1 1 . 4 - Twice o f the seismic load obtained from Equation (2.21) shall be consideredin the analysis of emergency electric back – up and fire fighting systems, for all equipment
attached to the infill walls and for their connections.

25

6.12. NON – BUILDING STRUCTURES

Non – building structures permitted to be analyzed in accordance with the requirements ofthis chapter and the corresponding Structural Behavior Factors, (R), to be applied tosuch structures are given in Table 2.8. Applicable seismic load reduction factors shall be
determined in accordance with Equation (2.3). Where applicable, Building Importance
Factors specified in Table 2.3 shall be used for non – building structures. However Live
Load Participation Factors specified in Table 2.7 shall not be applied. Except snowloads and crane payloads, unreduced weights of all solid and liquid materials stored andmechanical equipment shall be used.
TABLE 2.8 - STRUCTURAL SYSTEM BEHAVIOUR FACTORS FOR NONBUILDING STRUCTURES

TYPE OF STRUCTURE
Elevated liquid tanks, pressurized tanks, bunkers, vessels carried byframes of high ductility level or steel eccentric braced frames
Elevated liquid tanks, pressurized tanks, bunkers, vessels carried byframes of nominal ductility level or steel centric braced frames
Cast – in – situ reinforced concrete silos, industrial chimneys and suchlike
structural systems with uniformly distributed mass along height (*)
Reinforced concrete cooling towers (*)
Space truss steel towers, steel silos and industrial chimneys withuniformly distributed mass along height (*)
Guyed steel high posts and guyed steel
Inverted pendulum type structures carried by a single structural elementwith mass concentrated at the top
Industrial type steel storage racks

R
4
2
3
3
4
2
2
4

(*)Seismic analysis of such structures shall be performed in accordance with 2.8 or
2.9 by considering discrete dynamic degrees of freedom defining the structure sufficiently.
2.13. REQUIREMENTS FOR SEISMIC ANALYSIS REPORTS

The following requirements shall be applied for the analysis reports that include seismic
analysis of buildings:
2.13.1 – Types of irregularities specified in Table 2.1 shall be evaluated in detail for thebuilding to be designed and, if any, existing irregularities shall be identified.
2.13.2 – The selected structural system of high or nominal ductility level shall be clearly
defined with respect to the requirements of Chapter 3 or Chapter 4, and the selectionof the applicable R factor from Table 2.5 shall be explained.
2.13.3 – The selection of the applicable analysis method in accordance with 2.6 shall beclearly explained by considering the seismic zone in which the building exists, buildingheight and structural irregularities involved.

26

2.13.4 – The following rules shall be applied in the cases where the analysis isperformed by computer:(a) Analysis report shall include three-dimensional illustrations of structural system byindicating the joint and element numbering.
(b) All input data as well as output data including internal forces and displacements
shall be included in the analysis report in an easily understandable format. Whenrequested by the approval authority, all computer files shall be delivered in electronically.
(c) The title, author and the version of the computer software used in the analysis shallbe clearly indicated.
(d) When requested by the approval authority, theory manual and user’s guide of thecomputer software shall be included in the analysis report.
2.14. INSTALLATION OF ACCELEROMETERS

Upon endorsement by the Ministry of Public Works and Settlement, strong motion
accelerometer shall be permitted to be installed by the ministry or university institutions
on the public, private or corporate buildings and other structures for the purpose ofrecording the strong earthquake motions, and owners or operators of buildings or
structures shall be responsible from the safety of such instruments.

27

CHAPTER 3 - EARTHQUAKE RESISTANT DESIGN REQUIREMENTS FOR
REINFORCED CONCRETE BUILDINGS
2.0. NOTATIONS
Dimensioned expressions used in this chapter with the following notations are in

2

Newton [N] for forces, millimeter [mm] for lengths and Mega Pascal [MPa] = [N/mm ]for stresses.
Ac
Ach
Ack
Ae
Ag
Ak
Aos
Ap
As1
As2
Asd
Ash
Aw
a

Aw

bj

bk
bw
D
d
fcd
fck
fctd
fyd
fyk
fywk
Hcr

= Gross section area of column or wall end zone
= Gross section area of a solid wall, wall segment of a coupled wall, a floor or afloor segment of a perforated floor= Concrete core area within outer edges of confinement reinforcement= Effective shear area at any storey for the earthquake direction considered= Sum of section areas of structural elements at any storey behaving as structural
walls in the direction parallel to the earthquake direction considered= Sum of masonry infill wall areas (excluding door and window openings) at any
storey in the direction parallel to the earthquake direction considered= Section area of spiral reinforcement= Sum of plan areas of all stories of building= Total area of tension reinforcement placed on one side of the beam-column loop
at the top to resist the negative beam moment= Total area of tension reinforcement placed on the other side of the beam –column loop with respect to As1 at the bottom to resist negative beam moment= Total reinforcement area of each of the cross rebar bundles in coupling beam
= Along the height corresponding to transverse reinforcement spacing s, sum of
projections of cross section areas of all legs of hoops and crossties of columns orwall end zones in the direction perpendicular to bk considered= Effective web area of column cross section (excluding protrusions in the direction
perpendicular to the earthquake direction)= Sum of effective web areas of column cross sections, Aw’s at any storey= Lateral distance between legs of hoops and / or crossties of columns or wall end
regions= In the earthquake direction considered, column width in case the beam into thejoint has the same width as column or expands in both sides of the column,
otherwise twice the smaller of the distances measured from the vertical centerlineof beam to the edges of column (It shall not exceed beam width plus joint depth)= For each of the orthogonal lateral directions, cross section dimension of concretecore of column or wall end zone (distance between the centers or outermost
rebars)= Width of beam web, thickness of wall web= Concrete core diameter of circular column (distance between the centers of spiralreinforcement)= Effective beam height= Design compressive strength of concrete= Characteristic compressive cylinder strength of concrete= Design tensile strength of concrete= Design yield strength of longitudinal reinforcement= Characteristic yield strength of longitudinal reinforcement= Characteristic yield strength of transverse reinforcement= Critical wall height28

Hw= Total structural wall height measured from top foundation level or ground floorlevelh= Column cross section dimension in the earthquake direction consideredhk= Beam height= Development length of tensile reinforcement as given in TS-500b= Clear height of column between beams, clear span of beam between column ornwall faces= Length of wall or segment of coupled wall in planw
Ma
= Moment at the bottom of column clear height which is used for the calculation ofcolumn shear force(Md)t = Moment calculated under the combined effect of seismic loads and vertical loads
multiplied with load coefficients at the bottom section of structural wall.
Mpa = Moment capacity calculated at the bottom of column clear height by considering
fck, fyk and strain hardening of steel
Mpi= Positive or negative moment capacity calculated at column face on left end i of abeam by considering fck , fyk and strain hardening of steel
Mpj= Negative or positive moment capacity calculated at column face on right end j ofa beam by considering fck, fyk and strain hardening of steel
Mp = Sum of moment capacities of beams framing into a loop
Mpü = Ultimate moment capacity calculated at the top of column clear height byconsidering fck, fyk and strain hardening of steel(Md)t = Moment capacity calculated at the bottom section of wall by considering fck , fyk
and strain hardening of steel
Mra = Ultimate moment resistance calculated at the bottom of column or wall clear
height by considering fcd and fyd
Mri= Positive or negative ultimate moment resistance calculated at column or wall faceon left end i of a beam by considering fcd and fyd
Mrj= Negative or positive ultimate moment resistance calculated at column or wall faceon right end j of a beam by considering fcd and fyd(Mr)t = Ultimate moment resistance calculated at bottom section of wall by considering
fcd and fyd
Mrü = Ultimate moment resistance calculated at the top of column or wall clear heightby considering fcd and fyd
Mü= Moment at the top of column clear height which is used for the calculation ofcolumn shear force
Nd= Axial force calculated under combined effect of seismic loads and vertical loads
multiplied with load coefficients
Ndm = Greater of the axial pressure forces calculated under combined effect of seismic
loads and vertical loadss= Spacing of transverse reinforcement, step of spiral reinforcement
Vc= Contribution of concrete to shear strength
Vd= Shear force calculated under combined effect of seismic loads and vertical loads
multiplied with load coefficientsVdy= Simple beam – shear force developed at any section of the beam due to verticalloads
Ve= Shear force taken into account for the calculation of transverse reinforcement ofcolumn, beam or wall
Vik
= Sum of shear forces calculated in the earthquake direction considered inaccordance with Chapter 2 at all columns of the i’th storey

29

Vis
Vkol
Vr
Vt
αi

∅
γ
ρ
ρs
ρsh

= Sum of shear forces calculated in the earthquake direction considered inaccordance with Chapter 2 at the i’th storey columns where Equation (3.3) issatisfied at both bottom and top loops= Smaller of the shear forces at above and below the loop calculated in accordancewith Chapter 2= Shear strength of a section of column, beam or wall
= Total seismic load acting on a building (base shear) according to Chapter 2= Ratio of Vis / Vik calculated for any i’th storey= Reinforcement diameter= Angle of cross rebar bundle used in coupling beam with the horizontal axis
= Tension reinforcement ratio at the top and bottom of beam support section= Volumetric ratio of spiral reinforcement of column [ρs = 4 Aos / (D s)]= Volumetric ratio of horizontal web reinforcement of wall [(ρsh) min = 0.0025]

30

3.1. SCOPE
3.1.1 - Dimensioning and reinforcing of all structural elements of reinforced concretebuildings to be built in seismic zones shall be performed, along with currently enforced
relevant standards and codes, primarily in accordance with the requirements of thischapter. Requirements for reinforced concrete building foundations are given in
Chapter 6.
3.1.2 - Requirements and rules specified in this chapter are applicable to cast - in - situ
monolithic reinforced concrete buildings, and unless otherwise stated, prefabricatedbuildings whose structural systems are comprised of reinforced and / or pre - stressed
concrete elements.
3.1.3 - Lateral load carrying systems of reinforced concrete buildings covered in thischapter may be comprised of frames only, of walls only or of combination of frames
and walls.
3.1.4 - Reinforced concrete buildings with concrete strength exceeding that of C 50 andbuildings where steel profiles are used as reinforcement in structural elements are outside
the scope of this chapter.
3.2. GENERAL RULES
3.2.1. Classification of Reinforced Concrete Structural Systems

Lateral load resisting structural systems of reinforced concrete buildings shall beclassified with respect to their seismic behavior into two classes defined below.
Special cases and requirements regarding the mixed use of such classes of systems are
given in 2.5.4 of Chapter 2.
3.2.1.1 - Reinforced concrete structural systems given below are defined as Systems ofHigh Ductility Level:(a) Frame type structural systems comprised of columns and beams dimensioned andreinforced in accordance with the requirements of 3.3, 3.4 and 3.5.
(b) Structural systems comprised of solid or coupled structural walls dimensioned andreinforced in accordance with the requirements of 3.6.
(c) Frame - wall structural systems made of combining two systems defined above.
3.2.1.2 - Reinforced concrete structural systems given below are defined as Systems ofNominal Ductility Level:(a) Frame type structural systems comprised of columns and beams dimensioned andreinforced in accordance with the requirements of 3.7, 3.8 and 3.9.
(b) Structural systems comprised of solid or coupled structural walls dimensioned andreinforced in accordance with the requirements of 3.10.
(c) Frame - wall structural systems made of combining two systems defined above.

31

3.2.2. Relevant Standards

Cast - in - situ and prefabricated reinforced concrete structural systems shall be designed,along with the requirements of this chapter, according to the seismic loads and analysis
requirements given in Chapter 2, to other loads specified in TS - 498 and TS - 9967; andto the requirements as well as material and load factors specified in TS - 500, TS - 708,
TS - 3233 and TS - 9967.
3.2.3. Section Stiffnesses to be used in Structural Analysis

Section stiffnesses for uncracked sections shall be used in the structural analysis to be
performed with the methods given in Chapter 2. However respective values for cracked
sections may be used for beams framing into walls in their own plane and for coupling
beams of the coupled structural walls.
3.2.4. Method to be used in Section Design

The use of the Ultimate Strength Method given in TS - 500 is mandatory in earthquake
resistant dimensioning and reinforcement calculations of reinforced concrete structuralelements in all seismic zones.
3.2.5. Material
3.2.5.1 - In all buildings to be built in seismic zones, concrete with strength less than C
20 shall not be used.
3.2.5.2 - In all seismic zones, it is necessary t o u s e concrete produced with concrete
quality control requirements specified in TS - 500 and concrete placed with using vibrators.
However, in case of the usage of self - placed concretes, placing concrete with vibrator is
not required.
3.2.5.3 - Unribbed reinforcement steel can not be used exempt hoops and crossties withflooring reinforcement. With the exception of elements mentioned in 3.2.5.4 below,
reinforcing steel with strength exceeding that of S 420 shall not be used reinforced concrete
structural elements. The rupture strain of reinforcement to be used shall not be less than
10 %. Experimentally obtained average yield strength of reinforcing steel shall not be
more than 1.3 times the characteristic yield strength specified in the relevant steel standard.
In addition, experimentally obtained average rupture strength shall not be less than 1.25 times
the average yield strength obtained as well from the experiment.
3.2.5.4 - Reinforcing steel with strength exceeding that of S 420 may be used in flatslabs, in the slabs of joist floors, in peripheral external walls of basements, in the webs ofstructural walls of buildings in which entire seismic loads are resisted by such walls of fullbuilding height satisfying both of the conditions given by Equation (3.14) in 3.6.1.2, andas pre - stressing steel in prefabricated buildings.
3.2.6. Development Length of Tensile Reinforcement

Unless stated otherwise in this chapter, development lengths of tensile rebars with andwithout hooks shall be determined in accordance with TS - 500.

32

3.2.7. Welded Splices and Mechanically Connected Reinforcement
3.2.7.1 - Welded lap splices of longitudinal reinforcement shall be made bycertified welders. Butt weld splices shall not be permitted. Carbon equivalency of thereinforcement steel to be welded shall not exceed the limit value given in TS - 500.
3.2.7.2 - Tension test shall be applied to at least 2 % of welded splices and mechanicalconnections of longitudinal reinforcement provided that number of tests shall not be lessthan 5. Experimentally determined tensile strength of the connection shall not be lessthan the rupture strength given in TS - 500.
3.2.7.3 - Transverse reinforcement shall not be permitted to be welded to longitudinal
reinforcement.
3.2.7.4 - Frames of steel windows and doors, anchors, connection plates, elements ofplumbing system, machinery and equipment shall not be permitted to be welded
to longitudinal and transverse reinforcement.
3.2.8. Special Seismic Hoops and Crossties
Hoops and crossties used in columns, beam - column joints, wall end zones andbeam confinement zones of all reinforced concrete systems of high ductility level ornormal ductility level in all seismic zones shall be special seismic hoops and special
seismic crossties for which requirements are given below (Fig.3.1):

135°
Çap ≥ 5φetr≥ 6φ(10φ)≥ 80 mm (100 mm)

Figure 3.1
3.2.8.1 - Special seismic hoops shall always have 135 degree hooks at both ends.
However, 90 degree hook may be made at one end of the special seismic crossties. In thiscase, crossties with 135 degree and 90 degree hooks shall be placed on one face of acolumn or wall in a staggered form in both horizontal and vertical directions. 135
degree hooks shall be bent around a circle with at least 5∅ diameter where ∅ denotes the33diameter of transverse reinforcing bar. Lengths of hooks measured from tangent point shallnot be less than 10 ∅ and 100 mm for plain bars, 6∅ and 80 mm for ribbed bars.
3.2.8.2 - Special seismic hoops shall engage the longitudinal reinforcement from outsidewith hooks closed around the same rebar. Diameter and spacing of special seismic crossties
shall be the same as those of hoops. Crossties shall be connected to longitudinal
reinforcement always at both ends. Hoops and crossties shall be firmly tied such that theyshall not move during concrete pouring.
3.3. COLUMNS OF HIGH DUCTILITY LEVEL
3.3.1. Cross-section Requirements
3.3.1.1 - Shorter dimension of columns with rectangular section shall not be less than
250 mm and section area shall not be less than 75000 mm2. Diameter of circular columns
shall be at least 300 mm.
3.3.1.2 - In order the gross section are of column to be the biggest one of axial pressure
strengths calculated under the combined effect of Ndm vertical loads and seismic loads, grosssection area of column shall satisfy the condition Ac ≥ N dmax / (0.50 fck).
3.3.2. Longitudinal Reinforcement Requirements
3.3.2.1 - Longitudinal column reinforcement shall not be less than 1 %, nor shall it be morethan 4 % of gross section area. Minimum number of rebars shall be 4∅16 or 6∅14 forrectangular columns and 6∅14 for circular columns.
3.3.2.2 - Longitudinal reinforcement ratio shall not exceed 6 % at lap spliced sections.
3.3.3. Arrangement of Longitudinal Reinforcement
3.3.3.1 - Lap splices of column longitudinal reinforcement should be made, as much as
possible, within the column central zone defined in 3.3.4.2. In this case the splice length
shall be equal to the development length b given in TS - 500 for tension bars.
3.3.3.2 - In the case where lap splices of column longitudinal reinforcement are madeat the bottom end of the column, the following requirements shall be met:(a) In the case where 50 % of longitudinal reinforcement or less is spliced at the bottom
end of column, lap splice length shall be at least 1.25 times b.
(b) In the case where more than 50 % of longitudinal reinforcement is spliced at thebottom end of column, lap splice length shall be at least 1.5 times b. The same condition
shall apply to starter bars protruding from the foundation.
(c) In both cases given above, minimum transverse reinforcement defined in 3.3.4.1
shall be used along the length of the lap splice.

3.3.3.3 - In the case where the column cross-section changes between consecutive
stories, slope of the longitudinal reinforcement within the beam - column joint shall not be
more than 1 / 6 with respect to the vertical. When the change in cross section is more or in
the case of top storey columns; development length of the column longitudinal reinforcement
within the other side of the beam above shall not be less than 1.5 times the development
length b given in TS - 500 for tension reinforcement, nor shall it be less34

than 40 ∅. In the case of no beam present on the other side, development shall be achieved,
if necessary, by downward bending of rebar along the far face of the column. Length of
90 degree bent horizontal hook or downward bent vertical hook shall be at least 12∅(Fig. 2)

3.3.3.4 - Longitudinal distance between mechanical or welded connections on adjacentlongitudinal rebars shall not be less than 600 mm.

b

≥6

c

b
a

a
e

e

1

(a+b) ≥ 1.5 ℓb(a+b) ≥ 40 φb ≥ 12 φe ≥ 1.5 ℓbe ≥ 40 φ(a+b+c) ≥ 1.5 ℓb(a+b+c) ≥ 40 φc ≥ 12 φFigure 3.2
3.3.4. Transverse Reinforcement Requirements
Unless a more unfavorable situation governs in accordance with below given 3.3.7.6, theminimum transverse reinforcement requirements of columns are those specified in 3.3.4.1
for column confinement zones and in 3.3.4.2 for the column central zone (Fig.3.3).
Special seismic hoops and special seismic crossties defined in 3.2.8 shall be used along
the full length of the column.
3.3.4.1 - Special confinement zones shall be arranged at the bottom and top ends of eachcolumn. Length of each of the confinement zones shall not be less than smaller of column
cross section dimensions (diameter in circular columns), 1 / 6 the clear height of column
measured upward from floor level or downward from the bottom face of the deepest
beam framing into the column, and 500 mm. Such reinforcement shall be extended into
the foundation for a length equal to at least twice the smaller of column cross section
dimensions. Requirements for transverse reinforcement to be used in confinement zones
are given below. Those reinforcements shall be continued through the length not less than
25 times of the diameter of biggest longitudinal reinforcement and not less than 300 mm
inside the foundation. However, on the column which are supported to pot foundations,longitudinal reinforcements in the confinement zones shall be continued through thelength of the pot.

35

(a) Transverse reinforcement with a diameter less than ∅ 8 shall not be used inconfinement zones. Along the column, spacing of hoops and crossties shall not be morethan 1 / 3 the smaller cross section dimension and 100 mm, nor shall it be less than 50
mm. Lateral distance between legs of hoops and crossties, a, shall not be more than 25
times the hoop diameter. Pitch of the continuous spirals shall not be more than 1 / 5 thecore diameter and 80 mm.
(b) In the case where Nd > 0.20 Ac fck in columns with hoops, minimum total area oftransverse reinforcement to be used in confinement zones shall be calculated to satisfy themore unfavorable of the requirements given in Equation (3.1). In this calculation, core
diameter of column, bk, shall be considered separately for each direction (Fig. 3.3).
Ash ≥ 0.30 s bk [(Ac / Ack) − 1] (fck / fywk)
Ash ≥ 0.075 s bk (fck / fywk)(3.1)(c) In the case where Nd > 0.20 Ac fck in columns with spirals, minimum volumetric ratioof transverse reinforcement to be used in confinement zones shall be calculated to satisfy
the more unfavorable of the requirements given in Equation (3.2).
ρs ≥ 0.45 [(Ac / Ack) − 1] (fck / fywk)
ρs ≥ 0.12 (fck / fywk)(3.2)(d) In the case where Nd ≤ 0.20 Ac fck, at least 2 / 3 the transverse reinforcement given by
Equation (3.1) and Equation (3.2) shall be used as a minimum transverse reinforcement
in column confinement zones.
3.3.4.2 - Column central zone is the region between the confinement zones defined at thebottom and top ends of the column (Fig. 3.3). Transverse reinforcement with a diameter
less than ∅ 8 shall not be used along the column central zone. Along this zone, spacingof hoops and crossties shall not be more than half the smaller cross section dimension and
200 mm. Lateral distance between the legs of hoops and / or crossties, a, shall not be morethan 25 times the hoop diameter.
3.3.5. Requirement of Having Columns Stronger Than Beams
3.3.5.1 - In structural systems comprised of frames only or of combination of frames andwalls, sum of ultimate moment resistances of columns framing into a beam-column joint
shall be at least 20% more than the sum of ultimate moment resistances of beams framing
into the same joint (Fig. 3.4):(Mra + Mrü) ≥ 1.2 (Mri + Mrj)

(3.3)

3.3.5.2 - In order that Equation (3.3) is applied, beams framing into the joint shall satisfy
the dimensional requirements given in 3.4.1.1.
3.3.5.3 - Eq (3.3) shall be applied separately for both earthquake directions and senses toyield the most unfavorable result (Fig. 3.4). In calculating the column ultimate moment
resistances, axial forces Nd shall be taken to yield the minimum moments consistent with thesense of earthquake direction.

36

Figure 3.3

37

3.3.5.4 – Special situations regarding the application of Equation (7.3) are describedin the following:(a) Equation (3.3) need not to be applied in the case where Ndcolumns framing into the joint.
(b) Equation (3.3) need not to be checked in single storey buildings and in joints of
topmost storey of multi-storey buildings.
(c) Equation (3.3) need not to be checked in the case where a wall connected by beams
works like a column in its weak direction.
Earthquake
direction

Mra

Mra

Mrj

Mri

Earthquake
direction

Mri

Mrj

Mrü

Mrü

Figure 3.4
3.3.6. The Case Where Some Columns Cannot Satisfy the Requirement of Having
Columns Stronger Than Beams
3.3.6.1 – In structural systems comprised of frames only or of combination of walls andframes, Equation (3.3) may be permitted not to be satisfied in a given earthquake direction
at some joints at the bottom and / or top of an i’th storey, provided that Equation (3.4)
given below is satisfied.
αi = Vis /Vik ≥ 0.70

(3.4)

Nd ≤ 0.10 Ac fck may be taken into account in the calculation of Vis even if they do notsatisfy Equation (3.3).
3.3.6.2 – In the case where Equation (3.4) is satisfied, bending moments and shear forcesof columns satisfying Equation (3.3) at both bottom and top joints shall be
amplified by multiplying with the ratio (1/αi) within the range of 0.70 < αi < 1.00.
3.3.6.3 – In the case where Equation (3.4) is not satisfied at any storey, all frames ofstructural systems which may be comprised of frames only or of combination of walls
and frames shall be considered as frames of nominal ductility level, and theanalysis shall be repeated by changing the Structural Behavior Factor according to Table
2.5. As it is mentioned in 2.5.4.1 in Chapter 2, it is possible, however, to combine
frames of nominal ductility level with structural walls of high ductility level.

383.3.7. Shear Safety of Columns
3.3.7.1 – Shear force, Ve, to be taken into account for the design of column transverse
reinforcement shall be calculated by Equation (3.5).

Ve = (Ma + Mü) /

n

(3.5)

In determining Ma and Mü of Equation (3.5), below given 3.3.7.2 shall be applied forthe case where Equation (3.3) is satisfied at both bottom and top joints of the column,
whereas 3.3.7.3 shall be applied otherwise (Fig.3.5).
3.3.7.2 – Sum of ultimate moment capacities, Mp, at the ends of beams framing into thejoint where Equation (3.3) is satisfied shall be calculated:

Mp = Mpi + Mpj(3.6)

In the case where a more rigorous analysis is not performed, it may be assumed to be Mpi≅ 1.4 Mri and Mpj ≅ 1.4 Mrj. The moment Mp shall be distributed to columns in proportion
to the moments obtained in accordance with Chapter 2 at column ends framing into thejoint, and such distributed moments obtained at the bottom or top end of the column shallbe considered in Equation (3.5) as Ma or Mü, respectively. Equation (3.6) shall be applied
separately for both senses of earthquake direction and the largest value of Mp shall beconsidered in the distribution.
Even if Equation (3.3) is satisfied, calculation of Ma and Mü of Equation (3.5) may be
performed conservatively in accordance with below given 3.3.7.3.
3.3.7.3 – End moments of columns framing into the joint where Equation (3.3) is notsatisfied shall be calculated as the ultimate moment capacities and shall be substituted
into Equation (3.5) as Ma and / or Mü . In the case where a more rigorous analysis is not
performed, it may be assumed to be Mpa ≅ 1.4 Mra and Mpü ≅ 1.4 Mrü. In the calculation of
moments Mpa and Mpü, axial force Nd shall be taken into account so as to maximize thosemoments, being consistent with the sense of earthquake direction.
3.3.7.4 – The moment Ma at the bottom of a column framing into the foundation shall also
be calculated as the ultimate moment capacity in accordance with 3.3.7.3.
3.3.7.5 – Shear force ,Ve, obtained according to Equation (3.5), shall not be less than
the shear force calculated under factored gravity and seismic loads combined, and in
addition it shall satisfy the conditions given by Equation (3.7) below. In the case where
the condition given by Equation (3.7b) is not satisfied, cross section dimensions shall be
increased as required and the seismic analysis shall be repeated.

Ve ≤ Vr(3.7)
Ve ≤ 0.22 Aw fcd
3.3.7.6 – In calculating the column transverse reinforcement for shear force, Ve, contributionof concrete to the shear strength of the section, Vc, shall be determined in accordance with
TS - 500. However, in the calculation of transverse reinforcement along the column
confinement zones specified in 3.3.4.1, the coefficient of shearing force of concrete shall be39

taken as Vc= 0 in case shearing force made of only seismic loads is bigger than the halfof the total shearing force and at the same time provided the condition Nd ≤ 0.05 Ac fck.
Calculation of Mü

Calculation of Ma

Mhü(i): Moment obtained at top end of i’th storey column according to Chapter 2.
Mha(i): Moment obtained at bottom end of i’th storey column according to Chapter 2.

Figure 3.5
3.3.8. Conditions Related to Short Columns
Short columns may be developed due to structural arrangements or due to openings
provided in infill walls between columns (Fig. 3.6). In cases where short columns
cannot be avoided, shear force for transverse reinforcement shall be calculated by
Equation (3.5). The moments in Equation (3.5) shall be calculated at bottom andtop ends of the short column as Ma ≅1.4 Mra and Mü ≅1.4 rü with ln being the lengthof the short column. In addition, calculated shear force shall satisfy the conditions given
by Equation (3.7). The minimum transverse reinforcement requirements and conditionsof arrangement defined in 3.3.4.1 for column confinement zones shall be applied along
the length of the short column. Transverse reinforcement shall be extended along the fullstorey length of columns which are transformed into short columns in between infill
walls (Fig. 3.6)40

Ve
1.4 Mrüℓn
1.4 MraVe
Deep beamorInfill wall

Figure 3.6
3.4. BEAMS OF HIGH DUCTILITY LEVEL
3.4.1. Cross - section Requirements
3.4.1.1 – Dimensional requirements of cross - section of beams forming frames together
with columns, or of beams connected to structural walls in their own planes are given
below:(a) Width of the beam web shall be at least 250 mm. Web width shall not exceed thesum of the beam height and the width of the supporting column in theperpendicular direction to the beam axis.
(b) Beam height shall not be less than 3 times the thickness of floor slab and 300 mm,
nor shall it more than 3.5 times the beam web width.
(c) Beam height should not be more than 1 / 4 the clear span. Otherwise below given
3.4.2.5 shall be applied.
(d) Limitations specified above in relation to beam width and heights are not applicable
to reinforced concrete or pre - stressed / prefabricated beams with hinge connections
to columns, to coupling beams of coupled structural walls, and to the secondary
beams which are connected to frame beams outside the beam-column joints.
3.4.1.2 - It is essential that design axial force satisfies the condition Nd ≤ 0.1 Ac fck inorder that any structural element be sized and reinforced as a beam. Otherwise
such elements shall be sized and reinforced as a column in accordance with 3.3.
3.4.2. Longitudinal Reinforcement Requirements
3.4.2.1 – The requirement given by Equation (3.8) shall be applied as the minimum
ratio of top tension reinforcement at beams supports.
ρ ≥ 0.8 f ctd / f yd

(3.8)

41

3.4.2.2 – Diameter of longitudinal rebars shall not be less than 12 mm. At least two
rebars each at the bottom and top of the beam shall be continuously provided along thefull span length of the beam.
3.4.2.3 – In the first and second seismic zones, bottom reinforcement at a beam support
shall not be less than 50 % of the top reinforcement provided at the same support.
However this percentage may be decreased to 30 % in the third and fourth seismic
zones.
3.4.2.4 – Ratio of tensile reinforcement along beam spans and at supports shall not be
more than the maximum value specified in TS - 500 and 2 %.
3.4.2.5 – In the special cases where the condition given in paragraph (c) of 3.4.1.1 is notsatisfied, web reinforcement shall be provided along the beam height on both sides of
the web. Total area of web reinforcement shall not be less than 30 % of the greater of thesum of top and bottom longitudinal reinforcement at right or left support sections.
Diameter of web reinforcement shall not be less than 12 mm and spacing shall not be
more than 300 mm. For the development of web reinforcement similar to that oflongitudinal reinforcement, paragraph (b), and (c) of 3.4.3.1 shall be applied.
3.4.3. Arrangement of Longitudinal Reinforcement
3.4.3.1 – Requirements for the placement and development of the longitudinal reinforcement
are given below (Fig. 3.7):(a) At least 1 / 4 the maximum of the top support reinforcement at the ends of a beam
shall be extended continuously along the full span length. The remaining part of the top
support reinforcement shall be arranged in accordance with TS - 500.
(b) In cases where beams framing into columns are not extended to the other side ofcolumns, bottom and top beam reinforcement shall be extended up to the face of the otherside of the confined core of the column and then shall be bent 90 degrees from inside thehoops. In this case, total length of the horizontal part of the longitudinal rebar inside thecolumn and the 90 degree bent vertical part shall not be less than the straight development
length specified in TS - 500. Horizontal part of the 90 degree bent shall not be less than
0.4 b and vertical part shall not be less than 12 ∅. In walls and columns which
value is more than straight development length b and also more than 50 ∅, developmentof longitudinal reinforcement shall be provided straight without making 90 degree hook.
(c) In the case where beams frame into columns from both sides, beam bottom rebars
shall be extended to the adjacent span from the column face by at least the development
length b given in TS - 500. In cases where this is not possible because of reasons such as
the depth difference in beams, development shall be achieved in a way similar toparagraph(b) above, i.e., to the case where beam is not extended to the other side of
the column.
3.4.3.2 -Requirements related to splicing of longitudinal reinforcement are given below:(a) Lap splicing shall not be made along beam confinement zones defined in 3.4.4
below, within beam - column joints, and in regions where reinforcement has a possibility ofyielding, such as the mid-span region for bottom reinforcement. In places outside suchregions where lap splicing can be made, special seismic hoops defined in 3.2.8 shall be
used. Spacing of such hoops shall not exceed 1 / 4 of the beam depth and 100 mm. It is notnecessary to use special seismic hoops in the span center of the upper assembly rebar.

42

1 / 4 the max support reinforcement(See TS - 500 for other rules of arrangement)

Bottomreinforcement ofadjacent span

Bottomreinforcement ofadjacent span

Figure 3.7(b) Mechanical connections or welded lap splices shall only be applied to every alternate
bar at a section and longitudinal distance between two consecutive splices shall not be lessthan 600 mm.
3.4.4. Transverse Reinforcement Requirements

A region with a length twice the beam depth measured from the column face of a beam
support shall be defined as confinement zone and special seismic hoops defined in 3.2.8
shall be used along this region. In the confinement zone, distance of the first hoop to thecolumn face shall be max. 50 mm. Unless a more unfavorable value is obtained from
3.4.5.3, hoop spacing shall not exceed 1 / 4 of the beam depth, 8 times the minimum
diameter of the longitudinal reinforcement and 150 mm (Fig.3.8). Outside the confinementzone, minimum transverse reinforcement requirements specified in TS - 500 shall be applied.
3.4.5. Shear Safety of Beams
3.4.5.1 - Shear force, Ve, to be taken into account for beam transverse reinforcement shallbe calculated by Equation (3.9) such that the most unfavorable result is obtained byseparately considering the cases of earthquake acting from left to right or from right to left
(Fig.3.9).

Ve = Vdy ± (Mpi + Mpj) /

n

(3.9)

43

≤ 50 mm

sk

hk
Beam
Beam central zone
Confinement(Minimum transverse
zone
reinforcement according to TS-500)

Beam
Confinementzone= 2 hk= 2 hks k ≤ hk / 4
sk ≤ 8φ (φ = min. longitudinal rebar diameter)sk ≤ 150 mm

Figure 3.8

Unless a more rigorous analysis is performed, ultimate moment capacities at the beam ends
may be taken as Mpi ≅ 1.4 Mri and Mpj ≅ 1.4 Mrj.
3.4.5.2 – Shear force, Ve, calculated by Equation (3.9) shall satisfy the conditions given below
by Equation (3.10). In the case where the condition given by Equation (3.10b) is
not satisfied, cross-section dimensions shall be increased as required and the seismic
analysis shall be repeated.

Ve ≤ VrVe ≤ 0.22 bw d fcd(3.10)

3.4.5.3 - In calculating the beam transverse reinforcement for shear force, Ve,
contribution of concrete to the shear strength of the section, Vc, shall be determined inaccordance with TS - 500. However, in calculating the transverse reinforcement along thebeam confinement zones defined in 3.4.4, the coefficient of shearing force of concrete shallbe taken as Vc= 0 in case shearing force made of only seismic loads is bigger than the halfof the total shearing force. In no case shall the contribution of inclined longitudinal bars to
the shear strength be taken into account.
Mpj ≈1.4 Mrj

Mpi ≈1.4 Mri
i

j

ℓn
Vdyi

Vdyj
(Mpi + Mpj) / ℓnFigure 3.9

443.5. BEAM - COLUMN JOINTS OF FRAME SYSTEMS OF HIGH DUCTILITY LEVEL

3.5.1. Confined and Unconfined Joints

Beam - column joints of frame systems comprised of columns and beams of high ductility
level shall be separated into two classes as defined below.
(a) In the case where beams frame into all four sides of a column and where the width ofeach beam is not less than 3 / 4 the adjoining column width, such a beam-column joint shallbe defined as a confined joint.
(b) All joints not satisfying the above given conditions shall be defined as unconfined
joint.
3.5.2. Shear Safety of Beam-Column Joints
3.5.2.1 – Shear force in beam-column joints along the earthquake direction considered(Fig.3.10) shall be calculated by Equation (3.11).

Ve = 1.25 fyk (As1 + As2) − Vkol

(3.11)In the case where beam frames into column from only one side and discontinuous on theother side, it shall be As2 = 0.
3.5.2.2 – The shear force calculated by Equation (3.11) in a joint along the given
earthquake direction shall in no case exceed the limits given below (Fig.3.10). In thecases where those limits are exceeded, cross-section dimensions of column and/or beam
shall be increased and the seismic analysis shall be repeated.

Ve ≤ 0.60 bj h fcd(3.12)Ve ≤ 0.45 bj h fcd(3.13)

3.5.2.3 – Requirements for minimum transverse reinforcement in beam - column joints are
given below (Fig. 3.3):(a) In confined joints, at least 40 % of the amount of transverse reinforcement existing in
the confinement zone of the column below shall be provided along the height of the joint.
However, diameter of transverse reinforcement shall not be less than 8 mm and its spacing
shall not exceed 150 mm.
(b) In unconfined joints, at least 60 % of the amount of transverse reinforcement existing in
the confinement zone of the column below shall be provided along the height of the joint.
However in this case, diameter of transverse reinforcement shall not be less than 8 mm andits spacing shall not exceed 100 mm.

45Confined joint conditions
bw1 ve bw2 ≥ 3/4 b
bw3 ve bw4 ≥ 3/4 h(See 3.5.1)

bw2
bw3

Va
As1
1.25As1fyk
C1

C2
1.25As2fyk
As2Vü
Vkol = min (Va , Vü)

bw1

b1

b2

(Bkz. 3.5.2.1)bEarthquake
Direction

Figure 3.10bw4h

bj= b, In the case bw1 and bw2
In the case bw1 and bw2 < b
bj = 2 min (b1, b2)
bj ≤ (bw1 + h) (for bw1 < bw2)

b3.6. STRUCTURAL WALLS OF HIGH DUCTILITY LEVEL
3.6.1. Cross-Section Requirements
3.6.1.1 – Structural walls are the vertical elements of the structural system where the ratioof length to thickness in plan is equal to at least seven. With the exception of the special
case given in 3.6.1.2 and 3.6.1.3 below, wall thickness shall not be less than 1 / 20 thestorey height and 200 mm. In those walls, limits of the wall thickness in the end
points are given 3.6.2.1 below.
3.6.1.2 – In buildings where seismic loads are fully carried by structural walls along thefull height of building, wall thickness shall not be less than 1 / 20 the highest storey
height and 150 mm, provided that both two of the conditions given by Equation(3.14) are satisfied.

ΣAg / ΣAp ≥ 0.002
Vt / ΣAg ≤ 0.5 f ctd(3.14)

Equation (3.14) shall be applied at the ground floor level in buildings with stiff
peripheral walls in basement stories, whereas it shall be applied at foundation top levelfor other buildings.
3.6.1.3 – On the walls situated in lateral direction with the elements that the length is equal
to at least to 1 / 5 of the storey length and have storey length bigger than 6 m, wall46

thickness in the ground may be equal to at least 1 / 20 of horizontal length between
the points where its situated in lateral direction. However this thickness should not beless than 300 mm.
3.6.2. Wall End Zones and Critical Wall Height
3.6.2.1 - Wall end zones shall be developed on both ends of walls where Hw / w > 2.0(Fig. 3.11). With the exemption of buildings specified in 3.6.1.2, wall thickness shallnot be less than 1 / 15 of the storey height and 200 mm. In cases where wall end
zones situated to lateral direction with the elements that the length is equal to at least to 1 /5 of the storey height, wall thickness in the ground may be equal to at least 1 / 20 ofhorizontal length between the points where its situated in lateral direction. However
this thickness should not be less than 1 / 20 of the storey height and 300 mm. Wall end
zones may be developed within the wall itself or within an adjoining wall or in an
enlarged section at the edge of the wall.
3.6.2.2 – The critical wall height measured from the foundation level shall be
determined as to satisfy the unfavorable one of the following conditions given in
Equation (3.15) provided that it does not exceed 2 w .

Hcr ≥ w
(3.15)
Hcr ≥ Hw / 6
Here Hw, is the wall height measured from level that reduce more than 20 % of length of thewall in plan or from the top of the ground. In buildings where the stiffnesses of reinforced
concrete peripheral walls in basement stories are excessive compared to upper stories,
and where basement slabs behave as rigid diaphragms in horizontal planes, Hw and Hcrshall be considered upwards from the ground floor. In such buildings critical wall height
shall be extended downwards along the height of first basement storey below the groundfloor.
3.6.2.3 – In structural walls with rectangular cross section, the plan length of each of theend zones along the above defined critical wall height shall not be less than 20 % of thetotal plan length of the wall, nor shall it be two times the wall thickness. The plan lengthof each of the end zones along the wall section above the critical wall height shall not
be less than 10 % of the total plan length of the wall, nor shall it be less than the wall
thickness (Fig. 3.11).
3.6.2.4 – In the case where wall end zones are arranged within an adjoining walls or atenlarged sections at the edges of the wall, cross section area of each of the wall end zones shallbe equal at least to the area defined in 3.6.2.3 for rectangular section walls.
3.6.3. Web Reinforcement Requirements
3.6.3.1 – Total cross section area of each of the vertical and horizontal web reinforcement on
both faces of structural wall shall not be less than 0.0025 of the gross section area of thewall web remaining in between the wall end zones. In the case where Hw / w ≤ 2.0, wall
web section shall be considered as the full section of the wall. The spacing of
longitudinal and transverse reinforcement in wall web shall not be more than 250 mm(Fig. 3.11).

47

3.6.3.2 – In buildings where both conditions given by Equation(3.14) of 3.6.1.2 above
are satisfied, each of the total vertical and horizontal web reinforcement ratios may
be decreased to 0.0015. However in such a case, reinforcement spacing shall not
exceed 300 mm.
3.6.3.3 – Excluding the wall end zones, reinforcement mesh on both faces of the wall
web shall be tied each other by at least 4 special seismic crossties per unit square meterof the wall surface. However, excluding the wall end zones, at least 10 special seismic
crossties per unit square meter of the wall surface shall be used along the criticalwall height defined in 3.6.2.2. Crosstie diameter shall be at least equal to that of thehorizontal reinforcement.
3.6.4. Arrangement of Web Reinforcement

Horizontal web reinforcement may be arranged as explained below in 3.6.4.1 or in
3.6.4.2 (Fig. 3.11). Horizontal web reinforcement so arranged may be taken into accountin determining the confinement reinforcement to be provided in accordance with below
given 3.6.5.2 at wall end zones along the critical wall height.
3.6.4.1 – Horizontal web rebars shall be bent 90 degree at the outer edge of the wall end
zone and tied to the vertical corner reinforcement at the other face by a 135 degree
hook.
3.6.4.2 – In the case where horizontal web rebars are terminated at the wall end without 90
degree bent, ⊃ shaped horizontal bars with the same diameter of web reinforcement shallbe placed at both ends of the wall. Those bars shall be extended inside the wall web by atleast the development length measured from the inner boundary of the wall end zone.
However, in case development length of the web reinforcement is less than or equal tolength of wall end zone, ⊃ shaped bars should not be placed. In this case, total area of thetransverse in the wall end zones on unit length shall not less than the total area on the unit
length of the horizontal reinforcement in the wall web.
3.6.5. Reinforcement Requirements at Wall End Zones
3.6.5.1 – The ratio of the total area of vertical reinforcement at each wall end zone to thegross wall cross section area shall not be less than 0.001. However this ratio shall be
increased to 0.002 along the critical wall height defined in 3.6.2.2. Amount of verticalreinforcement at each wall end zone shall not be less than 4∅14 (Fig. 3.11).
3.6.5.2 – Vertical reinforcement at wall end zones shall be confined as similar tocolumns, by transverse reinforcement made of hoops and crossties, in accordance withthe below given rules.
(a) Diameter of transverse reinforcement to be used at wall end zones shall not be lessthan 8 mm. Horizontal distance between the legs of hoops and / or crossties, a, shall not
be more than 25 times the diameter of hoops or crossties.
(b) At least 2 / 3 of the transverse reinforcement determined by Equation(3.1) in 3.3.4.1
for the confinement zones of columns shall be provided at wall end zones along thecritical wall height defined in 3.6.2.2. Vertical spacing of hoops and / or crossties shallnot be more than half the wall thickness and 100 mm, nor shall it be less than 50 mm(Fig. 3.11). Such reinforcement shall be extended into the foundation by at least aheight equal to twice the wall thickness.

48

Wall and zone

Critical wall height

End zone

End zone

Wall and zone

SectionAlong the critical wall height

Outside the critical wall height

Figure 3.11(c) Vertical spacing of hoops and / or crossties at wall end zones outside the critical wallheight shall not be more than the wall thickness and 200 mm (Fig. 3.11).
3.6.6. Design Bending Moments
3.6.6.1 - In walls satisfying the condition Hw / w > 2.0, design bending moments along thecritical wall height determined according to 3.6.2.2 shall be taken as a constant value
being equal to the bending moment calculated at the wall base in accordance with Chapter
2. Above the critical wall height, a linear bending moment diagram shall be applicable49

(hich is parallel to the line connecting the moments calculated at the base and at the topof the wall (Fig. 3.12). In buildings with rigid peripheral walls at basements, the constantwall bending moment shall be considered along the critical wall height defined in 3.6.2.2.
In all sections of the walls satisfying Hw / w 2.0, design bending moments shall be taken
as equal to bending moments calculated according to Chapter 2.

Designbending
momentDesignbending
momentHw

Hw

Bending
moment(Analysis)

Bending
moment(Analysis)

Hcr

Hcr

Structural system comprisedof walls and frames

Structural system comprisedof walls only

Figure 3.12

3.6.6.2 – In the case where Hw / w > 2.0, ultimate moment resistances of wall crosssections at each storey shall satisfy in their strong direction the condition given
by Equation(3.3) for columns. Otherwise, seismic analysis shall be repeatedby increasing the wall dimensions and / or reinforcement.
3.6.6.3 – In walls satisfying the condition Hw / w > 2.0, design shear force based on thecalculation of any considered transverse reinforcement in section, Ve, shall be calculatedwith Equation (3.16).
Ve = β v(M p ) t(M d ) t

Vd(3.16)

Dynamic magnification coefficient of shear force placed in this correlation shall be taken
as v= 1.5. In the case where a more rigorous analysis is not performed, (Mp)t ≅ 1.4 (Mr)t
can be taken as the hardening moment capacity in the ground of wall. Design shear forcesin all section of the wall satisfying Hw / w 2.0, shall be taken as equal to shear forces
calculated according to Chapter 2.
3.6.7. Shear Safety of Structural Walls
3.6.7.1 – Shear strength of wall cross sections, Vr, shall be calculated by Equation (3.17).

Vr = Ach (0.65 fctd + ρsh fyd)(3.17)

50

The shear force Vd shall satisfy the conditions defined below:
Vd ≤ Vr
Vd ≤ 0.22 Ach fcd(3.18)

Otherwise transverse reinforcement of the wall and / or wall cross sections shall be
increased so as to satisfy the above conditions.
3.6.7.2 - By considering the shear force transferred to that section, vertical reinforcement atconstruction joints at the foundation level and at the above stories, shall be controlled withshear friction design defined in TS-500.
3.6.8. Rules and Requirements for Coupled Structural Walls
3.6.8.1 – All rules and requirements given above for structural walls are equally valid
for each of the wall segments forming the coupled structural walls.
3.6.8.2 – Sum of the base moments developed along the given earthquake direction at
the wall segments forming a coupled structural wall system shall not be more than 2 / 3
the total overturning moment developed in the coupled structural wall system due toseismic loads (Fig. 3.13). In the case where this condition is not satisfied, each of thewall segments forming the coupled structural wall shall be treated as a solid structuralwall, and R factor taken from Table 2.5 of Chapter 2 shall be changed accordingly.

Fwi

Hi

Msol
T

(Msol + Msağ) ≤ 2/3 ∑ (Fwi Hi)MsağT
Fwi: Seismic load acting at i’th storey oncoupled structural wall system

Figure 3.13

51

3.6.8.3 – In the reinforcement design of wall segments forming the coupled structuralwall, it may be allowed to transfer at most 30 % of the moment of the wall segment intension to the wall segment in compression (redistribution).
3.6.8.4 – Rules related to the shear reinforcement of coupling beams are given below:(a) In the case where any of the conditions below is satisfied, calculation of shear
reinforcement of coupling beams shall be performed in accordance with 3.4.5.
n > 3 hk
Vd ≤ 1.5 bw d fctd

(3.19)(b) In the case where none of the conditions given by Equation (3.19) is satisfied, thespecial shear reinforcement to be provided for the coupling beam shall be determinedby methods whose validity are proven by tests, or cross rebars shall be used to resist theshear of the coupling beam (Fig. 3.14). Total reinforcement area of each bundle of crossrebars shall be determined by Equation (3.20).

Asd = Vd / (2 fyd sin γ)(3.20)

There shall be at least four rebars in each bundle of cross rebars and they shall be
extended into the wall segments by at least 1.5 b. Bundles shall be confined with special
seismic hoops whose diameter shall not be more than 8 mm and their spacing shall not
be more than 8 times the cross rebar diameter and 100 mm. In addition to cross rebars,
coupling beam shall be provided with the minimum amount of hoops and horizontal
web reinforcement specified in TS-500 (Fig. 3.14).

Figure 3.14

3.7. COLUMNS OF NOMINAL DUCTILITY LEVEL
3.7.1. Cross - section Requirements

Cross - section requirements given in 3.3.1 for columns of high ductility level are equallyapplicable to columns of nominal ductility level.

523.7.2. Longitudinal Reinforcement Requirements

Longitudinal reinforcement requirements given in 3.3.2 for columns of high ductility
level are equally applicable to columns of nominal ductility level.
3.7.3. Arrangement of Longitudinal Reinforcement
Requirements related to the arrangement of longitudinal reinforcement given in 3.3.3
for columns of high ductility level are equally applicable to columns of nominal ductility
level.

In the case where reinforcement lap splices are made at the bottom end of the column,
minimum transverse reinforcement defined in 3.7.4.1 shall be used along the length of thelap splice.
3.7.4. Transverse Reinforcement Requirements
The minimum transverse reinforcement requirements of columns are specified in 3.7.4.1 forcolumn confinement zones and in 3.7.4.2 for the column central zone. Special seismic
hoops and special seismic crossties defined in 3.2.8 shall be used along all regions ofcolumn.
3.7.4.1 – The definition given in 3.3.4.1 for the length of each of the confinement zones isequally applicable to columns of nominal ductility level. In columns of nominal ductility
level, spacing of transverse reinforcement along the confinement zones shall not be morethan 1/ 3 of the cross - section size, 8 times of the diameter of minimum longitudinal
reinforcement and 150mm.
3.7.4.2 – In relation to the column central zone, definition and the minimumtransverse reinforcement requirements given in 3.3.4.2, as well as the conditions given in
3.3.4.3 are equally applicable to columns of nominal ductility level. Transverse
reinforcement in column central zone shall be determined in accordance with 3.7.5.3.
3.7.5. Shear Safety of Columns
3.7.5.1 – In columns of nominal ductility level, the shear force, Vd, obtained under
the combined effect of gravity loads and seismic loads given in Chapter 2 shall betaken into account in the determination of transverse reinforcement.
3.7.5.2 – In relation to the upper bound of shear force, the condition given by Equation(3.7) for columns of high ductility level is equally applicable to columns of nominal
ductility level, provided that Vd shall be considered in lieu of Ve .
3.7.5.3 – In the determination of transverse reinforcement according to the shear
force defined in 3.7.5.1, the contribution of concrete to the shear strength of thesection, Vc, shall be determined in accordance with TS - 500 by taking into accountthe minimum axial force, Nd, calculated under gravity loads combined with seismic loads.
3.7.6. Conditions Related to Short Columns
In relation to short columns, conditions given in 3.3.8 for columns of high ductility level are
equally applicable to columns of nominal ductility level.

533.8. BEAMS OF NOMINAL DUCTILITY LEVEL
3.8.1. Cross-section Requirements

Cross-section requirements given in 3.4.1.1 for beams of high ductility level are equallyapplicable to beams of nominal ductility level.
3.8.2. Longitudinal Reinforcement Requirements

Longitudinal reinforcement requirements given in 3.4.2 for beams of high ductility level are
equally applicable to beams of nominal ductility level.
3.8.3. Arrangement of Longitudinal Reinforcement

Requirements related to the arrangement of longitudinal reinforcement given in 3.4.3 forcolumns of high ductility level are equally applicable to columns of nominal ductility level.
3.8.4. Transverse Reinforcement Requirements

A region with a length twice the beam depth measured from the column face of a beam
support shall be defined as confinement zone and special seismic hoops defined in 3.2.8
shall be used along this region. In the confinement zone, distance of the first hoop to thecolumn face shall be max. 50 mm. Unless a more unfavorable value is obtained from the
below given 3.8.5, hoop spacing shall not exceed 1 / 3 o f the beam depth, 10 times theminimum diameter of the longitudinal reinforcement and 200 mm. Outside the confinementzone, minimum transverse reinforcement requirements specified in TS - 500 shall beapplied.
3.8.5. Shear Safety of Beams
3.8.5.1 – In beams of nominal ductility level, the shear force, Vd, obtained under the
combined effect of gravity loads and seismic loads given in Chapter 2 shall be taken
into account in the determination of transverse reinforcement.
3.8.5.2 – In relation to the upper bound of shear force, the condition given by Equation(3.10) for beams of high ductility level is equally applicable to beams of nominal
ductility level, provided that Vd shall be considered in lieu of Ve .
3.8.5.3 – In the determination of transverse reinforcement according to the shear force
defined in 3.8.5.1, the contribution of concrete to the shear strength of the section, Vc,
shall be determined in accordance with TS - 500. In no case shall the contribution of inclined
longitudinal bars to the shear strength be taken into account.
3.9. BEAM-COLUMN JOINTS OF FRAME SYSTEMS OF NOMINAL DUCTILITY
LEVEL

Rules and conditions given in 3.5 in relation to beam - column joints of frame systems
formed by columns and beams of high ductility level are equally applicable to beam column joints of systems of nominal ductility level with the exception of 3.5.2.1 and 3.5.2.2.

54

3.10. STRUCTURAL WALLS OF NOMINAL DUCTILITY LEVEL

Structural walls of nominal ductility level shall be dimensioned and reinforced inaccordance with the internal forces developed under the combined effect of gravity
loads and seismic loads. With the exception of rules and conditions given in 3.6.6, 3.6.8.2,
3.6.8.3 as well as the definitions and conditions given in relation to the critical wallheight, rules and conditions given in 3.6 for structural walls of high ductility level are
equally applicable to structural walls of nominal ductility level. However in 3.6.7.1, 1.5 Vdshall be taken instead of Ve.
3.11. SLABS
3.11.1 – Slabs shall possess sufficient stiffness and strength to enable the safe distributionof seismic loads acting on storey masses to the vertical elements of the structural system.
3.11.2 – In all seismic zones, slab thickness of all cast-in-situ or prefabricated, bare or
infilled joist floor systems shall not be less than 50 mm. However it is mandatory thatshear connectors be made between joists and the slab, and their adequacy be proven by
calculation to insure the safe transfer of in-plane shear forces developed under gravity
loads and seismic loads. Requirements given in TS - 500 for the slab thicknesses of otherfloor systems are applicable.
3.11.3 – In relation to the shear strength of slab systems, conditions given in 3.6.7 for the
shear strength of structural walls of high ductility level are equally applicable except 3.6.7.1.
3.12. SPECIAL REQUIREMENTS FOR PREFABRICATED BUILDINGS

Prefabricated buildings which are constructed through assembling the structuralelements manufactured in factory conditions shall comply with the following special
requirements in addition to the other requirements specified in this regulation.
3.12.1. Frames with Hinge Connections
3.12.1.1 – Hinge connections made of weld, shall possess sufficient strength to resist at least
2 times of the connection strength to be occurred from the earthquake according to Chapter
2 and other hinged connections shall also possess sufficient strength to resist at least 1.5 of
it. In confinement calculations safety tensions shall be increased maximum 15 %.
3.12.2. Moment Resisting Frames
3.12.2.1 – It shall be proven through analytical methods with appropriate referencesfrom the literature or tests that moment resisting connections of prefabricated building
frames possess strength and ductility that are equivalent to the monolithic behavior
under cyclic and repeated loading due to earthquakes.
3.12.2.2 – Connections shall possess sufficient strength to transfer moments, shear
forces and axial forces to be developed at the ultimate strength level without any
reduction in strength and ductility. In welded connections and other type of connections, 1.5
times and 1.2 times the seismic connection forces, respectively, obtained according to
Chapter 2 shall be taken into account.

55

3.12.2.3 – Connections must be arranged in sufficient distance from the potential plastic
hinges that can develop within the elements connected.
3.12.3. Conditions Concerning Pre - Stressing Elements

With the exception of floor elements and beam type elements with hinge connections to thecolumns, full pre - stressing shall not be permitted in prefabricated structural elements to be
used in seismic zones. Limited pre - stressing application, in addition to pre - stressing steel,can be provided by means of using pre - stressing steel in an amount to be obtained
sufficient ductility in elements or stressing of a pre - stressing steel with a low tensile force.
Tensile of the pre -stressing steel under the effects of earthquake shall not exceed the value
calculated with dividing the elastic limit to safety coefficient of material.
3.13. REQUIREMENTS FOR REINFORCED CONCRETE APPLICATION DESIGNDRAWINGS
3.13.1. General Requirements
3.13.1.1 – Quality classes of concrete and reinforcing steel to be used in the building
shall be indicated on all drawings.
3.13.1.2 – The Effective Ground Acceleration Coefficient, the Building Importance
Factor considered in the design, the Local Site Class selected from Table 6.2 and theStructural Behavior Factor determined from Table 2.5 shall be indicated on all floor
framing plan drawings.
3.13.1.3 – Hook bending detail of special seismic hoops and special seismic crossties
defined in 3.2.8 (Fig. 3.1) shall be shown on all detail drawings of columns, beams andstructural walls.
3.13.2. Column and Beam Details
3.13.2.1 – Position, diameter and number of vertical rebars within the cross - section
shall be shown in detail on column application drawings. Further, horizontal sections shallbe taken at each beam - column joint showing in plan the rebars extended upwards fromthe column below and longitudinal rebars of all beams framing into the column. Hence it
shall be clearly shown that column and beam rebars are arranged in such a way that theyshall not hinder the proper pouring of concrete into the joint. Ore reinforcement of wall andcolumn from the dig shall be indicated in the drawing with number, diameter and spacingwith expansions of transverse reinforcement concerning those.
3.13.2.2 – Vertical sections shall be taken with vertical rebar detailing clearly shown foreach type of column with fully identical longitudinal and transverse reinforcement.
Vertical columns sections shall include rebar splicing regions, lap lengths, beam - column
joint at the top of the column. In this respect, standard details valid for all beams - columns
joints of the building shall not be accepted.
3.13.2.3 – Lengths of column confinement zones as well as diameters, numbers, spacing
and cross-sectional details of transverse reinforcement provided along those regions,along the column central zone and within the top beam - column joint shall be clearly
indicated on the drawings, separately for each column type.

56

3.13.2.4 – In the application drawings of structural walls; positions, diameters andnumbers of vertical bars in the web and wall end zones shall be indicated. In addition,
vertical sections shall be taken for each wall type showing the vertical layout of rebars.
Critical wall height shall be clearly indicated on the vertical section. Diameters,
numbers, spacing and cross - sectional details of transverse reinforcement provided along
the critical wall height and other sections of the wall shall be clearly indicated on thedrawings.
3.13.3. Beam Details

In beam details, lengths of confinement zones at beam supports as well as diameters,
numbers, spacing and cross-sectional details of transverse reinforcement provided along
those regions and along the beam central zone shall be clearly indicated on thedrawings, separately for each beam.

57

CHAPTER 4 - EARTHQUAKE RESISTANT DESIGN REQUIREMENTS
FOR STRUCTURAL STEEL BUILDINGS
Dimensioned expressions used in this chapter with the following notations are in
Newton [N] for forces, millimeter [mm] for lengths and MegaPascal [MPa] = [N/mm2] forstresses.
4.0. NOTATION

A
Ak
An
b
bcf
bbf
D
Da
db
dc
E
Es
e
G
Havr
h
hi
b
n

Md
Mp
Mpa
Mpi
Mpj
Mpn
Mpü
Mvi
Mvj
Nbp
Nçp
Nd
Q
R
ry
t
tbf
tcf
tmin
tp

= Area of Cross - Section= Area of shearing= Useful cross - section area
= Width= Flange width of column section= Flange width of beam section= Outside diameter in circular ring sections= Increase coefficient of yield stress= Length of cross - section beam
= Length of cross - section column= Notation for seismic load
= Elasticity modulus of structural steel= Length of bond beam
= Notation for dead load
= Average storey heights on the up and down of the loop point= Height of web plate= Storey height of the i’th floor of the building= Distance between the points where the beam is supported in lateral direction= Distance between the possible plastic joint points in the edges of the beams= Bending moment calculated under the combined effects of seismic loads andgravity loads= Bending moment capacity calculated at the bottom end of the column= Moment calculated at the bottom end of column= Positive or negative plastic moment calculated at the left end i of the beam
= Negative or positive plastic moment calculated at the right end j of the beam
= Reduced moment capacity= Moment calculated at the top end of column= Additional bending moment occurred on the surface of the column due toshearing force in the possible plastic joints at the left end i of the beam
= Additional bending moment occurred on the surface of the column due toshearing force in the possible plastic joints at the right end j of the beam
= Axial pressure capacity= Axial tensile capacity= Factored axial force calculated under simultaneous action of vertical loads andseismic loads= Notation for live load
= Behavioral coefficient of structural system= Radius inertia in the lateral direction of the 1 / 3 of the part that is under thecompressive strength of the beam flange and web= Thickness= Flange thickness of the beam section= Flange thickness of the column section= Minimum plate thickness in the sliding zone
= Including the reinforcing plates, total plate thickness in the sliding zone

58

tt
tw
u
Vd
Vdy
Ve
Vke
Vik
Vis

Vp
Vpn
Wp

αi

i
p
o
a
bem
em

p

= Thickness of the reinforcing plate= Web thickness= Length of the periphery of reinforcing plate= Shearing force calculated under the combined effect of gravity loads andseismic loads= Simple beam shearing force occurred due to gravity loads in the surface of thebeam which combines with column= Necessary shearing strength of the beam - column confinement zone
= Necessary shearing strength of the sliding zone
= Sum of shear forces calculated in the earthquake direction considered inaccordance with Chapter 2 at all columns of the i’th storey in the peripheries offramed or framed - wall systems= Sum of shear forces calculated in the earthquake direction considered inaccordance with Chapter 2 at the i’th storey columns where Equation (4.3) issatisfied at both bottom and top joints in the peripheries of framed or framed wall systems= Shearing force capacity= Reduced shearing force capacity= Plastic moment of resistance= Ratio of Vis / Vik calculated for any i’th storey= Relative storey drift at the i’th floor of the building= Turning angle of the bond beam
= Increase coefficient= Yield stress of the structural steel= Depending on the slenderness of the element, pressure safety stress calculated
according to TS - 648= Safety stress= Relative floor drift angle

594.1. SCOPE
4.1.1 - Dimensioning of all structural elements of structural steel buildings to be built inseismic zones and design of their joints shall be performed, along with currently
enforced relevant standards and codes, primarily in accordance with the requirements ofthis chapter.
4.1.2 - Lateral load carrying systems of structural steel buildings covered in this chapter
may be comprised of steel frames only, of steel braced frames only or of combination offrames with steel braced frames or reinforced concrete structural walls. Steel carrying
systems of armoured concrete floorings that work compositely with the steel beams are also
under the scope of this Chapter.
4.1.3 - Requirements for structural steel building foundations are given in Chapter 6.
4.2. GENERAL RULES
4.2.1. Classification of Steel Structural Systems

Lateral load carrying systems of structural steel buildings shall be classified withrespect to their seismic behavior into two classes defined in 4.2.1.1 and 4.2.1.2 below.
Special cases and requirements regarding the mixed use of such classes of systems are
given in 2.5.4 of Chapter 2 and also in 4.2.1.3 and 4.2.1.4. In the case where reinforced
concrete structural walls are used as part of the structural system, rules given in 3.6 or 3.10
of Chapter 3 shall be applied.
4.2.1.1 - Structural steel systems given below are defined as Systems of High Ductility
Level:(a) Frame type structural systems complying with the requirements of 4.3.
(b) Lateral carrying systems comprised of centric steel braced frames that provides theconditions specified in 4.6 and centric steel braced frames complying with the requirementsof 4.8.
(c) Steel braced wall - frame systems made of combining the two systems defined inparagraph (a) and (b) above.
4.2.1.2 – Structural steel systems given below are defined as Systems of Nominal
Ductility Level:(a) Frame type structural systems complying with the requirements of 4.4.
(b) Structural systems comprised of concentric steel braced frames complying with therequirements of 4.7.
(c) Steel braced wall - frame systems made of combining the two systems defined
above.
4.2.1.3 – In case the lateral load carrying systems specified above are differ from eachother in both two lateral seismic direction, conditions of R coefficients are given in 2.5.1.2
and 2.5.1.3 and also conditions concerning R coefficients to be applied in mixed use inany direction are given in 2.5.4.
60

4.2.1.4 – Conditions concerning steel or armored concrete - steel combined buildings
consist maximum two different lateral carrying system in vertical direction and R
coefficients to be applied to those are given in 2.5.5.2.
4.2.2. Relevant Standards
4.2.2.1 - Design of structural steel systems covered in the scope of this chapter
shall be performed according to the seismic loads and analysis requirements given in
Chapter 2 of this Specification, to other loads specified in TS - 498, to the requirementsof TS - 648 based on allowable stress method. In special cases where the rules in relevant
standards are different, rules in this Chapter shall be taken as basis.
4.2.2.1 - For the matters outside the rules given in this Chapter, rules in TS - 3357 and TS 648 shall be complied. based on allowable stress method and to those of TS - 4561
based on ultimate strength design method. For the matters outside the scope of thosestandards and hereby Regulation, then it can be benefited from the internationally accepted
standards and regulations.
4.2.3. Material Conditions and Material Safety Factors
4.2.3.1 – Within the scope of this Regulation, all structural steels that have weld ability
and defined in the other internally accepted standards or in TS - 648 can be used. On
the plates that have at least 50 mm thickness on the rolling profiles with 40 mm walled
thickness of flanges and artificial profiles made of those plates, minimum value ofCharpy - V - Notch (CVN) (Notch Resistance) shall be 27 Nm (27 J) in 218 C on thetests carried out in accordance with ASTM A673 or equivalent standards.
4.2.3.2 – Bolts to be used in the combination and joints of the elements under the effect ofseismic load shall be ISO 8.8, 10.9 or high quality. These bolts shall be pre - stressed withall pre - stress strength applicable to them in the joints that transmit moment, whereas on theother joints those shall be pre - stressed with half of it. ISO 4.6 and 5.6 quality bolts can beused in the combinations and joints of the elements that are not under the effect of seismic
loads and in the details of foundation connections.
4.2.3.3 – On the welded joints, electrodes shall be used in accordance with the steel material
and welded method and yield strength of the electrode will not be less than the yieldstrength of the combined materials. On the welded column - beam joints of the frames thattransmit moment, full penetration butt weld or butt wells seams shall be used. On theminimum value of electrodes of Charpy - V - Notch (CVN) (Notch Resistance) shall be
27 Nm (27 J) in - 298 C in those welds.
4.2.3.4 – On the elements that are under the effect of seismic load, welded and bolted joints
can not be used together in the same joint points.
4.2.3.5 – On the section calculations made according to Safety Stress Method under the
combined effect of gravity loads and seismic loads, safety stresses shall be increased utmost
33 %. On the design of combinations and joints based on the safety stresses, this increment
will not exceed 15 %. Also combinations and joints shall be controlled according to element
capacities or increased seismic effects in such a way that specified in the relevant articles ofthis Chapter.

61

4.2.3.6 – As prescribed in the articles 4.3.2.1, 4.3.4.1, 4.8.6 and 4.9.1 of this Chapter, on thecalculation of required capacities of structural steel elements and joint details, values of
Da a increased yield stress shall be used instead of the value of yield stress a. Da factors to
be used in the calculation of increased yield stress are given in the Table 4.1 depending on
the class and element type of the structural steel.
TABLE 4.1 – Da INCREASE COEFFICIENTSClass and Element Type of Structural Steel

Rolling profiles made of Fe 37 steel
Rolling profiles made of other structural steels
Plates made of all structural steels

Da
1.2
1.1
1.1

4.2.4. Increased Seismic Effects

On the required points of the articles 4.3.1.2, 4.3.5.3, 4.4.2.1, 4.4.2.3, 4.6.3.1, 4.6.5.2,
4.7.2.1, 4.8.6.4 and 4.9.1 of this Chapter, on the design of structural steel elements andcombination details, increased seismic effects given below are taken into consideration.
Loads that give increased seismic effects are defined as:
1.0 G + 1.0 Q ± Ωo E

(4.1a)

0. 9 G ± Ω 0 E(4.1b)

Or in case of unfavorable results
Values of Increase Coefficient, Ωo, to be applied to internal forces formed of seismic loads
calculated according to Chapter 2, are given in the Table 4.2 depending on the types ofstructural steel systems.
TABLE 4.2 – INCREASE COEFFICIENTSType of Structural SystemsΩoFrames Of High Ductility Level
Frames Of Normal Ductility Level
Centric Steel Braced Frames (Frames of High or Normal Ductility Level)
Eccentric Steel Braced Frames

2.5
2.0
2.0
2.5

4.2.5. Inner Force Capacities and Boundary Values of Tensile

In order to use in necessary cases, tensile boundary values of inner force capacities andboundary values of tensile of the structural elements are defined as follows:
Inner force capacities of structural elements:
Bending moment capacity: M p = Wp σa(4.2a)

Shearing force capacity: Vp = 0.60 σa Ak(4.2b)

Axial pressure capacity: N bp = 1.7 σbem A(4.2c)

Axial tensile capacity: N çp = σa Anet

(4.2d)

Tensile Boundary Values of Combination Elements:

62

Full penetration weld
Partial penetration butt weld
Or filled weld
Bolted combinations: σa: 1.7 σem
: 1.7 σem

Here, σem indicates safety stresses of relevant combination element (normal stress, sliding
and crushing stress).
4.3. FRAMES OF HIGH DUCTILITY LEVEL

Rules to be respected in dimensioning of the frames of high ductility level are given
below.
4.3.1. Cross-section Requirements
4.3.1.1 - Requirements concerning flange width / thickness ratio and web depth / thickness
ratio of the frames of high ductility level in the beams - columns are given in Table 4.3.
4.3.1.2 - Besides providing necessary tensile controls under the axial force and bending
moments occur due to the combined effect of gravity loads and seismic, columns shall also
have the sufficient resistance capacity under the axial pressure and tensile force (without
considering bending moments) occur from the condition of increased load according toEquation (4.1a) and Equation (4.1b) in the first and second seismic zones. Axial pressure
and tensile capacities of column cross - sections shall be calculated with Equation (4.2c)
and Equation (4.2d).
4.3.2. Requirement of Having Columns Stronger Than Beams
4.3.2.1 - In frame systems or in the frames of frame - wall (braced frame) systems, sum of
the plastic moments of columns framing into a beam - column joint in the earthquake
direction shall be bigger than 1.1Da times of the total of bending moment capacities on thesurface of the beams which joint in that loop point (Fig. 4.1):

Earthquake
direction

Mpa

Mpa

Earthquake
direction

Mpj
Mpj

Mpi
Mpi

Mpü

Figure 4.1

Mpü

63

TABLE 4.3 – CROSS - SECTION CONDITIONSLimit Values
Description of
Slenderness
Systems of High Ductility
Systems of Normal
Elements
RatiosLevel
Ductility Level
I Sections
U Sections
b/t
0.3 Es σ a
0.4 Es σ aUnder bending effect
I Sections
U Sections
Under bending effect
T Sections
L Sections
Under pressure effecth/tw

3.2 Es σ a

4.0 Es σ a

h/tw

0.3 Es σ a

0.4 Es σ aFor, N d σ a A
I Sections
U Sections
Under bending andpressure effects

0.10

For, N d σ a A

0.10

Nd
σa A

4.0 Es σ a 1 − 1.7

Nd
σa A

3.2 Es σ a 1 − 1.7

h/twFor, N d σ a A > 0.10
1.33 Es σ a 2.1 −Circular ring sections
under bending oraxial pressure effect(pipes)D/t

0.05

Rectangular sections
under bending oraxial pressure effect

b/t
or
h/tw

0.7 Es σ a

Nd
σa A

For, N d σ a A > 0.10
1.66 Es σ a 2.1 −

Es

σa

0.07

Nd
σa A

Es

σa

1.1 Es σ a

Descriptionsb:

Width of half - flange in I sections
U sections and flange width in rectangular sectionsh:

I , U , T sections and web length in rectangular sections
long side length in L sections

D:

Outer diameter in the circular ring sections (in pipes)t:

I , U , T sections and flange thickness in rectangular sections
thickness in the circular sections (pipes)

tw:

I , U , T, L sections and web thickness in rectangular sections

64

(Mpa + Mpü) ≥ 1.1Da (Mpi + Mvj + Mpj + Mvj)

(4.3)

In case of using weakened beam sections or forming gussets at the end of beams, terms of
Mvj and Mvj in this equation, indicate the additional bending moments occurred on thesurface of the column due to shearing forces in the possible plastic joints at the end zones ofbeam. In case plastic moments form in the beam’s sections of the surface of columns, theseterms take zero value.
4.3.2.2 - Equation (4.3) shall be applied separately for both senses of earthquake direction
to yield the most unfavorable result. In calculating the column plastic moments, axial forces
shall be considered to yield the minimum moments capacities with the sense of earthquake
direction.
4.3.2.3 - Equation (4.3) need not to be checked in single storey buildings and in joints of
topmost storey of multi - storey buildings.
4.3.3. The Case Where Some Columns Cannot Satisfy the Requirement of Having
Columns Stronger Than Beams
4.3.3.1 – In structural systems comprised of frames only or of combination of frames
and walls (braced frames), Equation (4.3) may be permitted not to be satisfied in a given
earthquake direction at some joints at the bottom and / or top of an i’th storey, provided
that Equation (4.4) given below is satisfied.
αi = Vis / Vik ≥ 0.70

(4.4)

4.3.3.2 – In the case where Equation (4.4) is satisfied, bending moments and shear forcesof columns satisfying Equation (4.3) at both bottom and top joints shall be amplified bymultiplying with the ratio (1 / αi) within the range of 0.70 < αi < 1.00. In the case wherecolumns is not satisfied Equation (4.3), it shall be calculated under the effects ofgravity load and seismic load forming its sections.
4.3.3.3 – In the case where Equation (4.4) is not satisfied at any storey, all frames ofstructural systems which may be comprised of frames only or of combination of frames
and walls shall be considered as Frames of Nominal Ductility Level, and the analysis shallbe repeated by changing the Structural Behavior Factor according to Table 2.5. As it ismentioned in 2.5.4.1 in Chapter 2, it is possible, however, to combine frames of nominal
ductility level with structural walls of high ductility level.
4.3.4. Confinement Zones of Beam - Column
4.3.4.1 – In the beam - column joints that transfer moment of the frames with high ductility
level, the following three conditions shall be covered together:a) Confinement shall have the capacity to be provided at least 0.04 radian Angle of Relative
Storey Drift (relative storey drift / storey height). Therefore, details that availability isproved with scientific and / or analytical methods shall be used. Several samples of bolted
and welded confinement detail and application boundaries of them are given in Information
Annex 4A.

65b) Necessary bending strength of the joint on the surface of the column will not be less than
0.80 X 1.1Da times of the bending moment capacity on the surface of column of combined
beam. However, upper limit of this strength shall conform to the biggest bending momenttransferred to confinement by joint columns to loop point. Additionally, it will not exceed
the bending moment occurred under the combined effects of seismic loads calculated for the
R = 1.5 value of the reduced coefficient of gravity loads and seismic loads. In case of using
weakened beam cross - sections or forming gussets at the end zones of the beams, capacityof bending moment on the surface of column shall be calculated by adding beam plastic
moment with additional bending moments occurred on the surface of the column due toshearing forces in the possible plastic joints at the end zones of beam.
c) Shearing force, Ve, to be based on dimensioning of the joint shall be calculated with
Equation (4.5).
(M pi + M pj )Ve = Vdy ± 1.1 Da(4.5)ℓn
4.3.4.2 – On the calculation of combination’s bearing capacity, tensile boundary values
given in the 4.2.5 shall be used.
4.3.4.3 – On the calculation of the bearing capacity of the combination, sliding zone limitedby column and beam flanges shall be dimensioned provided the following conditions:a) Necessary shearing strength, Vke, of the sliding zone shall be taken equal to shearing
force occurred 0.80 times of the sum of bending moment capacities of beams on the surfaceof the column combined at the loop point.
1
1
Vke = 0.8 ∑ M p ( −(4.6))
d b H ort

kayma bölgesi

V ke

t bf

süreklilik levhaları
db

V ke
t cf

dc

Figure 4.2

66b) Shearing force capacity, Vp, shall be calculated with the following Equation:
 3b t 2 
Vp = 0.6 σa d c tp 1 + cf cf  d b d c tp (4.7)

In order to sliding zone to have necessary shearing strength the following condition has tobe provided:
Vp ≥ Vke(4.8)
In case this condition is not provided, necessary amount of reinforcing plate shall be used or
strutting plates shall be added to sliding zone diagonally.

c) Minimum thickness, t min, of the each web plates of the column and reinforcing plates, if
used, shall be provided the below condition (Figure 4.3).
tmin ≥ u / 180(4.9)

In cases where this condition is not provided, by welding interoperation of reinforcing plates
and web plate of the column and it shall be controlled whether the sum of plate thicknesses
provide the Equation (4.9) or not.

d) In cases where reinforcing plates are used in sliding zone, for connecting those plates tocap plates of column, full penetrated butt weld or fillet weld shall be used. These welds shallbe controlled in such a way that safely transfer shearing force corresponded by reinforcing
plate. On this calculation, welding stress capacities given in (4.2.5) shall be used.
Reinforcing plates

tt
t
tt

tt
t
tt
t min = min ( t , t t )
(a)

(b)

Figure 4.3
4.3.4.4 – In details of beam - column joints that transfer moment, by placing ductility plates
on both sides of column web in the level of beam flanges, it shall be provided to safely
transfer the tensile and pressure strengths on the beam ends to column (and to next beam in
the bilateral beam - column joints).

a) Thicknesses of ductility plates shall not be less than the cap thickness of the combined
beam in the unilateral beam joints where not less than the biggest flange thickness of the
combined beams in case there are bilateral beam combinations to column.
b) Full penetration butt weld shall be used for the connection of ductility plates to webs andflanges of column. For the connection of the ductility plate to column web, fillet weld canalso be used. (Figure 4.2). However, this weld should have the thickness and length to67

transfer a force equal to shearing force in the plane of ductility plate to column web.

c) Ductility plate can not be required if the flange thickness of column provides thefollowing two conditions:tcf ≥ 0.54 bbf tbf

andbtcf ≥ bf
6

(4.10a)(4.10b)4.3.5 – Column and Beam Splices
4.3.5.1 – Column splices made with full penetration butt weld or bolted shall be away frombeam - column joint by at least 1 / 3 of the net storey height. Additionally, this distance shallnot less than 1.20 m in the splices made of with fillet weld or butt weld without full
penetration.
4.3.5.2 – Beam splices shall be made away from the beam - column connection by a distanceat least two times of the beam height.
4.3.5.3 – Bending capacity of the column - beam splices shall not be less than the bending
capacity of the combined element and also shearing force capacity shall not be less than thevalue given in Equation (4.5). Besides, in the first and second seismic zones, axial force
capacity of the column splices shall be also sufficient under the axial pressure and tensile
force (without considering bending moments) calculated with Equation (4.1a) andEquation (4.1b). On the calculation of bearing capacities of the additional elements,
boundary tensile values of weld and bolt given in (4.2.5) shall be used.
4.3.6 – Supporting the Beam Flanges Laterally
4.3.6.1 – Up and down flanges of the beams shall be supported laterally. b distance between
the points where the beams are supported shall provide the following condition.

b≤ 0.086

ry E sσa(4.11)In addition, points effected by the single loads, points where beam cross - section changes
suddenly and points where plastic hinge can occur during the non - linear deformation of thesystem shall also be supported.

4.3.6.2 – Necessary pressure and tensile strength of lateral supports shall not be less than
0.02 of the axial tensile capacity of beam flange.
4.3.6.3 – On the systems where armoured concrete floorings operate compositely with steel
beams, it is not necessary to comply above conditions at the flanges of the beams bonded tothe armoured concrete flooring.

684.4. FRAMES OF NOMINAL DUCTILITY LEVEL
Rules to be respected on the calculation of frames of nominal ductility level are given
below.

4.4.1 – Cross - Section Conditions
4.4.1.1 - Requirements concerning flange width / thickness ratio and web depth / thickness
ratio of the frames of nominal ductility level in the beams - columns are given in Table 4.3.
However provided with the control of necessary local buckling, exceeding these boundaries
can be permitted in utmost two storey buildings.
4.4.1.2 - Requirements given above in 4.3.1.2 for the columns of frames of high ductility
level are also applicable to frames of nominal ductility level.
4.4.1.3 - Requirements given above in 4.3.2, 4.3.3 for frames of high ductility level are notmandatory to be applied for frames of nominal ductility level.
4.4.2 – Confinement Zones of Beam - Column
4.4.2.1 – Necessary tensile controls shall be carried out under internal forces occurred fromthe combined effect of gravity loads and seismic loads in the confinements of beam column of the frames of nominal ductility level. Besides, bearing capacity of the
combination shall provide the smallest ones of the internal forces defined below:a) Bending moment capacity of the beam which combined the column calculated in such a
way defined in 4.3.4.1 (b) and necessary shearing force strength calculated with Equation(4.5).
b) Bending moment and shear force occurred due to increased load situations given in the
Equation (4.1a) and Equation (4.1.b).
4.4.2.2 – On the calculation of the confinement’s bearing capacity, boundary values oftensile given in 4.2.5 shall be used.
4.4.2.3 – In the detail of beam column confinement, sliding zone (Figure 4.2) which islimited by the flanges of column and beam shall be dimensioned in a way that provides thefollowing conditions.

a) On the calculation of necessary shearing force strength of Sliding Zone, Vke, theshearing force occurred due to increased seismic load given in Equation (4.1a) andEquation (4.1b) and the smallest one of shearing force calculated with Equation (4.6) shallbe used.
b) Shearing force strength of the sliding zone, Vp, shall be calculated with Equation (4.7).
In order sliding zone to have sufficient shearing strength it is necessary to provided
Equation (4.8).
c) Rules given in 4.3.4.3 [c] and 4.3.4.3 (d) for the calculation of sliding zone of frames ofhigh ductility level are also available for the frames of nominal ductility level.

694.4.2.4 – Rules given in 4.3.4.4 for the calculation of continuity plates in the frames of highductility level are also available for the frames of nominal ductility level.
4.4.3 – Column and Beam Joints
Rules given in 4.3.5 for the joints of column and beam in frames of high ductility level are alsoavailable for the frames of nominal ductility level.

4.5 - CENTRIC AND ECCENTRIC STEEL BRACED FRAMES
Steel braced frames of high ductility level are defined as lateral load resisting structuralelements comprised of hinged joints or frames that transfer moment with braces connected
centrically and eccentrically to them. Lateral load bearing capacity of such kind of systems,
besides bending strengths, mostly or completely provided with the axial force strengths ofthe elements. Steel braced frames are divided into two depending on the order of braces:a) Centric Steel Braced Frames (Figure 4.4)b) Eccentric Steel Braced Frames (Figure 4.5)
Centric Steel Braced Frames in which the braces are connected centrically to loop points offrames can be dimensioned as the systems of high ductility level or the systems of nominal
ductility level. On the other hand, Eccentric Steel Braced Frames in which the braces areconnected eccentrically to loop points of frames can be dimensioned as the systems of highductility level.

Diyagonal çapraz

X çapraz

Ters V çapraz

V çapraz

K çapraz

Figure 4.4
kiri

ba kiri i

e

kolon

e

e

e

az
pr
ça

Figure 4.5704.6. STEEL BRACED FRAMES OF HIGH DUCTILITY LEVEL
Steel braced frames of high ductility level, even in case of buckling of some pressure
elements, are dimensioned in a way that avoid significant strength loss in the system.
Requirements to be applied in the dimensioning of such systems are as specified below:

4.6.1. Conditions of Cross Section
4.6.1.1 - Requirements concerning flange width / thickness ratio and web depth / thickness
ratio of the frames of high ductility level in the beams - columns and braces are given in
Table 4.3.
4.6.1.2 - Slenderness ratio (bar buckling length / radius of inertia) at all pressure elementsof roof and vertical plane brace systems shall not be exceed 4.0 E s / σ a4.6.1.3 - Spaces of brace plates in multi - partite crosses shall be determined in such a waythat slenderness ratio of the single element between two sequential brace plates does notexceed 0.40 times the slenderness ratio of all bar. In case it is shown that buckling of themulti - partite cross does not shearing effect on brace plate, spaces of brace plates shall be
determined in such a way that slenderness ratio of the single bar between two brace plates
does not exceed 0.75 times the active slenderness ratio of multi - partite bar. Total shearing
force capacity of brace plates shall not less than axial the tensile capacity of each bar
element. In each bar at least two brace plate shall be used and the plates shall be placed as
equal intermittently. Bolt brace plates are not permitted to place on middle three - third ofclear space of the bar.
4.6.2. Transfer of Horizontal Loads
Vertical centric cross elements on one axis of the building shall be arranged in such a waythat at least 30 % and utmost 70 % of horizontal forces affected in the earthquake on the
direction of that axis and on each direction of the earthquake cover by crosses which operate
when pushed.

4.6.3. Joints of Crosses
4.6.3.1 - On the joint details of crosses, necessary tensile controls shall be made under theinternal forces formed of the combined effect of gravity loads and earthquake. Besides,
bearing capacity of the joint shall also provide the smallest one of the internal forces define
below.
a) Axial force (tensile or pressure) capacity of crossb) Depending on the capacities of other elements combined at the loop point, the biggest
axial force that can transfer to mentioned crossc) Transverse axial force occurred due to increased load conditions as given in Equation(4.1.a) and Equation (4.1b).
4.6.3.2 - On the calculation of the bearing capacity of joint, boundary values of tensile asgiven in 4.2.5 shall be used.

71

4.6.3.3 - Plates of loop point that tie crosses to columns and / or beams shall also provide
the following two conditions:a) Bending capacity in the plane of loop point’s plate shall not less than the bending
capacity of the cross jointed to loop point.
b) In order to prevent buckling of loop point’s plate outside the plane, distance of the endof cross to the surface of beam or column shall not more than two times of the thickness ofloop plate. In cases where this rule is not followed,
4.6.4 - Additional Conditions for Special Cross Arrangements
4.6.4.1 - Additional conditions that have to be provided by V - shaped or opposite V shaped cross systems are given below:a) Beams which connect to crosses shall be perpetual.
b) Crosses shall be dimensioned under the effect of gravity loads and seismic loads.
However, in case the crosses are ignored, beams and end joints which are connected tocrosses shall be dimensioned in a way that carries safely the gravity loads on itself.
c) Conditions given in 4.3.6 for the beams of frames of high ductility level are alsoavailable for the beams which are connected to crosses.
4.6.4.2 - K - shaped (where the crosses are connected to mid point of the column) crossorder is not permitted for eccentric steel braced frames with high ductility level.
4.6.5 - Joints of Column
4.6.5.1 - Column joints shall be made at the center of 1 / 3 zone of column free level.
4.6.5.2 - Bending strength of column joints shall not less than 50 % of the bending capacityof combined smallest elements whereas shear force strength shall not less than the shearing
capacity of the combined smallest elements. Besides, it shall be sufficient under the axial
force bearing power of the column joints (without considering bending moments) andtensile and pressure forces formed due to increased seismic loads as given in Equation(4.1a) and Equation (4.1b) in the first and second seismic zones. On calculation of joint
elements, weld and bolt tensile capacities ad given in 4.2.5 shall be used.
4.7. CENTRIC STEEL BRACED FRAMES WITH NOMINAL DUCTILITY LEVEL
Rules to be applies on the steel braced frames of nominal ductility level are specified blow.
4.7.1. Conditions of Cross - Section
4.7.1.1 - Requirements concerning flange width / thickness ratio and web depth / thickness
ratio of the frames of nominal ductility level in the beams - columns are given in Table 4.3.
However provided with the control of necessary local buckling, exceeding these boundaries
can be permitted in utmost two storey buildings.
4.7.1.2 - Slenderness ratio (bar buckling length / radius of inertia) at all pressure elementsof roof and vertical plane brace systems shall not be exceed 4.0 E s / σ a72

4.7.1.3 - Rules concerning brace plates of TS 648 on the multi - partite crosses areapplicable. At least two brace plate shall be used in each bar.
4.7.1.4 - In the case where braces are designed to resist tension only, slenderness ratio ofbraces shall not exceed 250. However, this rule may not be applied in case the crosselements in utmost two storey buildings are dimensioned in such a way that carries themultiplication of tensile force calculated according to Chapter 2 and coefficient in Table
4.2.
4.7.2. Joints of Crosses
4.7.2.1 - On the joint details of crosses, necessary tensile controls shall be made under theinternal forces formed of the combined effect of gravity loads and earthquake. Besides,
bearing capacity of the joint shall also provide the smallest one of the internal forces define
below:a) Axial force (tensile or pressure) capacity of crossb) Transverse axial force occurred due to increased load conditions as given in Equation(4.1.a) and Equation (4.1b).
c) The biggest force to be transferred to the mentioned cross by the other elements
combined to loop point.
4.7.3.2 - On the calculation of the bearing capacity of joint, boundary values of tensile asgiven in 4.2.5 shall be used.
4.7.2.3 - Requirements given in 4.6.3.3 for centric steel braced frames of high ductility level
are also available for the centric steel braced frames of nominal ductility level.
4.7.3. Additional Conditions for Special Cross Arrangements
4.7.3.1 - Requirements given in 4.6.4.1 (a) and 4.6.4.1 (b) for centric steel braced frames ofhigh ductility level are also available for the centric steel braced frames of nominal ductility
level.
4.7.3.2 - Conditions given in 4.4.4 for the beams of frames of nominal ductility level arealso available for the beams which are connected to crosses.
4.8. ECCENTRIC STEEL BRACED FRAMES OF HIGH DUCTILITY LEVEL
Eccentric steel braced frames of high ductility level are the horizontal structural systems inwhich brace plates under the seismic effects have the feature of significant non - linear
deformation. These systems, during the plastic deformation of brace plates, are dimensioned
in a way that provide other beams, except columns, crosses and brace plates, remain inelastic zone. Requirements to be applied in dimensioning of the eccentric steel braced
frames of high ductility level are given below.
4.8.1. Conditions of Cross - Section
4.8.1.1 - Requirements concerning flange width / thickness ratio and web depth / thickness
ratio of the frames of nominal ductility level in the beams - columns are given in Table 4.3.
However provided with the control of necessary local buckling, exceeding these boundaries
can be permitted in utmost two storey buildings.

73

4.8.1.2 - Slenderness ratio (bar buckling length / radius of inertia) at all pressure elementsof roof and vertical plane brace systems shall not be exceed 4.0 E s / σ a4.8.1.3 - Conditions given in 4.4.4 for the multi - partite crosses are also available for theeccentric steel braced frames.
4.8.2. Brace Beams
4.8.2.1 - In the eccentric steel braced frames of high ductility level, there shall be one brace
beam at least one end of each cross element.
4.8.2.2 - Length of the brace beam, except the special condition in 4.8.8.1, may be
determined as follow.

1.0 M p / Vp ≤ e ≤ 5.0 M p / Vp

(4.13)

Mp bending moment and Vp shear force capacity in this correlation shall be accounted with
Equation (4.2a) and Equation (4.2b).

4.8.2.3 - Brace beams shall be dimensioned under the design internal forces (shear force,
bending moment and axial force) formed of seismic effects calculated according to Chapter
2 and gravity loads.
4.8.2.4 - Design shear load of brace beam, Vd, shall provide the both following conditions.
(4.14)
Vd ≤ Vp

Vd ≤ 2M p / e
4.8.2.5 - In case the axial design force of brace beam is,
N d / σa A > 0.15

(4.15)(4.16)

Following values shall be used in Equation (4.14) and Equation (4.15) instead of Mp, and VpN
M pn = 1.18 M p 1 − d
σa A
Vpn = Vp 1 − (N d /σ a A) 2

(4.18)

4.8.2.6 - Web plate of the brace beam shall be single - piece and there won’t be any support
plate in the web plane. There won’t be any spacing on web plate.
4.8.3. Lateral Supporting of the Brace Beam
4.8.3.1 - Up and bottom flanges of brace beam shall be supported on both ends of the beam
whereas in brace beams arranged on the side of column shall be laterally supported on one
end of the beam. Necessary strength of lateral supports shall not be less than 0.006 of theaxial tensile capacity of beam flange.

744.8.3.2 - Beside beam section outside the brace beam shall be supported laterally with
0.45bbf Es / σ a spaces. Necessary strength of these supports shall not be less than 0.001 of
the axial tensile capacity of beam flange.

4.8.3.3 - In the steel structural systems where armoured slabs operate compositely with steel
beams it is not necessary to obey the above conditions.
4.8.4. Turning Angle of Brace Beams
Depending on the relative storey drift of i’th storey in which brace beam is locateddefined in Chapter 2,i,∆i(4.19)
hi
Due to the angle of storey drift determined with above equation, p turning angle of brace
beam occurred between brace beam and storey beam of this beam’s extension shall not
exceed the boundary values as given below (Figure 4.6):
p

R

hi

i

=R

R

e

γp

θp

hi

e

i

θp
γp

L

L

γp = L θpeγp = L θp
e

e
R

hi

e

i

θp

γp

L
γp = L θp
2eFigure 4.675

(a) 0.10 radian in case the length of brace beam is equal to or smaller than 1.6 Mp / Vp.
(b) 0.03 radian in case the length of brace beam is equal to or smaller than 2.6 Mp / Vp.
Linear interpolation shall be made in case the length of brace beam is between these twoboundary values.

4.8.5. Rigidity (Stiffening) Plates
4.8.5.1 – Rigidity plates shall be placed at the end of cross elements where the crosselements directly transfer load to brace beam and extensions. Rigidity plates unlessotherwise stated, shall be placed on both sides of the web plate of brace beam and shall bein the length as web plate and in the width as half flange plate (Figure 4.7).Thickness ofrigidity plates shall not less than 0.75 of the thickness of web plate and 10 mm. Constantfillet welds that connect rigidity plates to web of the brace beam shall have the capacity totransfer forces formed of the multiplication of cross - section area of rigidity plates andyield stress of material.
rijitlik levhaları (4.8.5.1)
çapraz ve ba kiri ieksenleri ba kiri iiçinde kesi ecektir.

süreklikö ekayna ıeaaara rijitlik
levhaları(4.8.5.2)

rijitliklevhalarıa-a kesiti

Figure 4.7
4.8.5.2 – In addition to the rigidity plates at the end of connection beams inter rigidity
plates as defined below shall be placed:(a) On the brace beams with a length smaller than 1.6 Mp / Vp, inter - spaces of interrigidity plates shall not be less than (30 tw – db / 5) incase turning angle of brace beam is
0.10 radian whereas it shall not be less than (52 tw – db / 5) in case turning angle of brace
beam is smaller than 0.03. Linear interpolation shall be made for the inter values ofturning angle.
(b) On the brace beams with length taller than 2.6 M p / Vp and shorter than 5M p / Vp , oneeach rigidity plate shall be placed 1.5bbf distance from the end of brace beams.

(c) On the brace beams with a length between 1.6 M p / Vp and 2.6 M p / Vp , inter rigidity
plates as specified in (a) and (b) shall be used together.

(d) On the brace beams with a length taller than 5M p / Vp , inter rigidity plates may not be
used.

76

4.8.6. Crosses, Storey Beams and Columns
4.8.6.1 – Load that causes plasticity of the brace beam shall be determined by means of
the multiplication of internal forces formed due to seismic loads and calculated according
to Chapter 2 with the biggest one of the Mp Md and Vp / Vd Design Increment Factors
calculated as a result of section choose in the brace beam.
4.8.6.2 – Crosses shall be dimensioned according to internal forces formed of 1.25Da
times of load that causes the plasticity of brace beam.
4.8.6.3 – Section storey beam located outside the brace beam shall be dimensioned
according to internal forces formed of 1.1Da times of load that causes the plasticity ofbrace beam.
4.8.6.4 – Necessary tensile controls shall be made on the columns under internal forces
formed of the combined effect of gravity loads and seismic loads. Besides, bearing capacityof the column shall also provide the smallest one of the internal forces define below:(a) Internal forces formed of 1.1Da times of load that causes the plasticity of brace beam.
(b) Internal forces occurred due to increased load conditions as given in Equation (4.1.a)and Equation (4.1b).
4.8.6.5 – Internal force capacities of the cross - sections of crosses, storey beams andcolumns shall be calculated with the correlations as given in Equation (4.2).
4.8.7. Joint of Cross and Brace Beam
Joint details of crosses with brace beam shall be dimensioned according to internal forces
calculated as specified in 4.8.6.2.

4.8.8. Joint of Brace Beam - Column
4.8.8.1 – Length of the brace beam that joints to column shall provide the following
condition:e ≤ 1.6M p / Vp

(4.20)

4.8.8.2 – Necessary bending and shearing strengths of joint on the surface of column shallrespectively not be less than the capacity of bending moment of brace beam, Mp, andshearing force Vp. Full penetration butt welding shall be applied for the connection ofbrace beam flanges to column (Figure 4.8).

77

rijitlik levhaları(4.8.5.1)
çapraz ve ba kiri ieksenleri ba kiri iiçinde kesi ecektir.

süreklikö ekayna ıeaaara rijitlik
levhaları(4.8.5.2)

rijitliklevhalarıa-a kesiti

tam penetrasyonlu
küt kaynak

4.8.9 Beam - Column Joint

Figure 4.8

Joint details of the part of storey beam with column located outside the brace beam shallbe made as hinged inside the beam - web plane. However, this connection shall bedimensioned transversely as equal to 0.01 of the axial tensile capacity of beam flanges andaccording to buckling moment formed by forces with opposite direction.

4.9. DETAILS OF FOUNDATION CONNECTION
4.9.1 – On the foundation details of the elements of structural steel system, necessary
tensile controls shall be made by predicating the support reactions formed of the combined
effect of gravity loads and seismic loads. Besides, bearing capacity of the detail offoundation connection shall also provide smallest ones among the internal forces define
below:(a) The bending moment formed of 1.1Da times of the bending moment capacity ofcolumn which joints to foundation with total gravity and horizontal forces formed of
1.1Da times of the axial load capacities of column and crosses which joint to foundation.
(b) Internal forces occurred due to increased load conditions as given in Equation (4.1.a)and Equation (4.1b).
4.9.2 – Boundary tensile values as given in 4.2.5 shall be used on the calculation of the
bearing capacity of connection detail.

78

4.10. RULES CONCERNING THE STATEMENT
IMPLEMENTATION PROJECTSOFPROJECT

AND

4.10.1. Statement of Project
4.10.1.1 – Information specified in 2.13 of Chapter 2 shall be in the statement of project
concerning the statement of earthquake.
4.10.1.2 – Besides, information listed below shall be in the statement of project:(a) Material qualities and characteristic strengths of the latten and profile that forms
structural system with bolts used in the joints and confinements, type of electrode.
(b) Loads that give the increased seismic effects and load combinations based on design.
4.10.1.3– Besides the dimensioning calculations of structural elements and verifications ofstability, calculations of combination and joint details with capacity control verifications
concerning these details shall be given in detailed in the scope of the project statement.
4.10.2. Rules Concerning the Drawings of Steel Implementation Project
4.10.2.1 – Following sections shall be in the steel implementation projects:(a) General construction plans concerning roof slabs and storey slabs(b) Column implantation (layout) plan(c) Anchorage plan and details(d) Front views and sections in sufficient amount(e) Detailed drawings of columns and beams that composed the structural system withcrosses of roof, horizontal plane and vertical plane(f) Details of all combinations and joints
4.10.2.2 – Material qualities of profiles and latten used in building with bolt types used in
combinations with the type of electrodes to be used shall be specified in all sections.
4.10.2.3 – Factor of Effective Ground Acceleration, Building Importance Factor, Local
Soil Class as considered in design and Load - Bearing System Behavioral Factor
determined according to Table 2.5 shall be specified in all construction sections.
4.10.2.4 – In the details of blot combination and joints, type of used bolt, diameters ofbolts and drills, features of washer and nuts with pre - stress force to be implied to bolts
shall be specified.
4.10.2.5 – Weld type, thickness of weld and welding length to be implied shall be given indetails of welded combinations and joints and also geometrical sizes of welding bent shallbe given in butt welds which require to open welding bent.

79

INFORMATION ANNEX 4A – BEAM - COLUMN COMBINATION DETAILS IN
MOMENT TRANSFERRED FRAMES
4A.0. NOTATIONS
bbf
db= Flange width of beam section= Height of beam cross - section

4A.1. SCOPE AND GENERAL MATTERS
4A.1.1 – As estimated in 4.3.4.1 (a), in this Chapter several bolted and welded
combination details samples are given which are proved with scientific and / or analyticalmethods that the samples have the capacity to provide at least 0.04 radian Relative Storey
Drift Angle (relative storey drift / storey height)1.
4A.1.2 – These details may be used within the limits of implementation concerning
moment transferred beam - column combinations of frames of high ductility level.
4A.1.3 – As for the moment transferred beam - column combinations of frames of
nominal ductility level those mentioned details may be used definitively.
4A.1.4 – Strength calculations and capacity control verifications of combination details
shall be carried out in accordance with 4.3.4 and 4.4.2 respectively for the frames of
nominal and high ductility level.
4A.2. COMBINATION DETAILS OF BEAM - COLUMN
Implementation boundaries that contain combination details of bolted and welded momenttransferred beam - column with the usage terms of these details in frames of high ductility
level are given below.

4A.2.1. Combination Details for Bolted Rider Plate
Beam - column combination detail for bolted rider plate is given in Figure 4A.1. In thedetail, rider plate made of Fe 37 steel combined to flange plates of beam with full
penetration butt weld and also combined to web plate with double - sided fillet weld. For
the connection of rider plate to column, full pre - stressed bolts with at least ISO 8.8
quality shall be used.
For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.1.

1

Federal Emergency Management Agency (FEMA) (2000), Recommended Seismic Design Criteria for
New Steel Moment-Frame Buildings, FEMA 350, FEMA, Washington, D.C.

80

Fe 37 alın levhası
tam penetrasyonlu küt kaynak
takviye levhaları(gerekti inde)süreklilik levhaları(gerekti inde)en az ISO 8.8 kalitesindetam öngermeli bulon
im (gerekti inde)

Figure 4A.1
TABLE 4A.1 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF BOLTED RIDER PLATE BEAM - COLUMN
Parameter of Combination Detail
Cross - section height of beam
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Class of bolt
Conditions of bolted pre - stress
Material class of rider plate
Weld of flange plate

Implementation Boundaries
750 mm
7
20 mm
600 mm8.8 or 10.9
Full pre - stress
Fe 37
Full penetration butt weld

4A.2.2. Combination Details of Supported Rider Plate Beam - Column
Beam - column combination detail for bolted rider plate supported with rigidity plates isgiven in Figure 4A.2. In the detail, rider plate made of Fe 37 steel combined to flange
plates of beam with butt weld and also combined to rigidity plate with double - sided fillet
weld. For the connection of rider plate to column, full pre - stressed bolts with at least ISO
8.8 quality shall be used.
For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.2.

81

Fe 37 alın levhası

25

rijitlik levhası
tam penetrasyonlu küt kaynak

takviye levhaları(gerekti inde)

25

süreklilik levhaları(gerekti inde)30°

en az ISO 8.8 kalitesindetam öngermeli bulon

im (gerekti inde)

Figure 4A.2
TABLE 4A.2 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF BOLTED SUPPORTED RIDER PLATE BEAM - COLUMN
Parameter of Combination Detail
Cross - section height of beam
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Class of bolt
Conditions of bolted pre - stress
Material class of rider plate
Weld of flange plate

Implementation Boundaries
1000 mm
7
25 mm
600 mm8.8 or 10.9
Full pre - stress
Fe 37
Full penetration butt weld

4A.2.3. Combination Details of Bolted Non - Rider Plate
Beam - column combination detail for bolted non- rider plate is given in Figure 4A.3. In
the detail, connection of beam to column is provided with joint flange plate and sliding
plate in web. Joint flange plate combined to column with butt weld and also sliding platecombined with butt weld and fillet weld. For the connection of beam flange and web
plates to joint flange plate and sliding plate, bolts with at least ISO 8.8 quality shall beused.
For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.3.

82

veya

tam penetrasyonlu
küt kaynak
en az ISO 8.8 kalitesindetam öngermeli bulon

takviye levhaları(gerekti inde)en az ISO 8.8
kalitesinde bulon
süreklilik levhaları(gerekti inde)veya
kayma levhası

im(gerekti inde)
ek ba lık levhası

Figure 4A.3
TABLE 4A.3 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF BOLTED NON - RIDER PLATE BEAM - COLUMN
Parameter of Combination Detail
Cross - section height of beam
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Class of bolt
Biggest bolt size
Pre - stress Conditions of flange plate bolts
Material class of joint flange plate
Weld of joint flange plate

Implementation Boundaries
800 mm
8
20 mm
600 mm8.8 or 10.9
M 30
Full pre - stress
Fe 37, Fe 52
Full penetration butt weld

4A.2.4. Welded Combination Detail
Welded combination detail is given in Figure 4A.4. In the detail, connection of beamflange plates to column is provided with full penetration butt weld. Web plate of beamcombined to column by using sliding plate with butt weld and also fillet weld. As shownin detail, access spaces for weld are necessary for butt welds in beam flanges.
For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.4.

83

tam penetrasyonlu küt kaynak

25

50
takviye levhaları(gerekti inde)montaj bulonu
süreklilik levhaları(gerekti inde)veya
kayma levhası

kaynak ula ımdeli iFigure 4A.4
TABLE 4A.4 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF WELDED BEAM - COLUMN
Parameter of Combination Detail
Cross - section height of beam
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Access space for weld
Weld of flange plate

Implementation Boundaries
1000 mm
7
25 mm
600 mmNecessary
Full penetration butt weld

4A.2.5. Combination Detail for Welded Joint Flange Plate
Combination detail for welded joint flange plate is given in Figure A4.5. In the detail,combination of joint flange plates to column is provided with full penetration butt weld
and combination to beam flange is provided with peripheral fillet weld. Web plate ofbeam combined to column by using sliding plate with butt weld and also fillet weld.
Access spaces for weld are not necessary in this detail.

For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.5.

84

ek ba lık levhası

veya

tam penetrasyonlu
küt kaynak

ek ba lık levhası
takviye levhaları(gerekti inde)kayma levhası
montaj bulonu
süreklilik levhaları(gerekti inde)

veya

Figure 4A.5
TABLE 4A.5 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF WELDED BEAM - COLUMN WITH JOINT FLANGE
Parameter of Combination Detail
Cross - section height of beam
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Material of joint flange plate
Weld of joint flange plate

Implementation Boundaries
1000 mm
7
25 mm
600 mmFe 52
Full penetration butt weld

4A.2.6. Welded Combination Detail of Weakened Beam Cross - Section
Welded combination detail of weakened beam cross - section is given in Figure 4A.6. In
the detail which has same features with welded combination detail, additionally weakened
cross - section beam is used. Estimated geometrical sizes for weakened beam cross section are shown in figure.
For the implementation of this detail on frames of high ductility level, it is necessary forthe parameters of combination detail to provide the implementation boundary given in
Table 4A.6.

85

yarıçap~= 0.80 d b
0.5-0.75 b bf

0.65-0.85 d bb bf

0.20-0.25 b bf
zayıflatılmı
kiri enkesiti
takviye levhaları(gerekti inde)montaj bulonudbsüreklilik levhaları(gerekti inde)veya
kayma levhası
kaynak ula ım deli itam penetrasyonlu küt kaynak( ekil 4A.4 'e bakınız.)

Figure 4A.6

TABLE 4A.6 – IMPLEMENTATION BOUNDARIES OF THE COMBINATIONDETAILSOF BEAM - COLUMN WELDED WITH WEAKENED BEAM CROSS SECTION
Parameter of Combination Detail
Cross - section height of beam
Weight of beam unit length
Ratio of beam spacing / cross - section heightThickness of beam flange
Cross - section height of column
Access space for weld
Weld of joint flange plate

Implementation Boundaries
1000 mm≤ 450 kg/m
7
45 mm
600 mmNecessary
Full penetration butt weld

86

CHAPTER 5 – EARTHQUAKE RESISTANT DESIGN REQUIREMENTS FOR
MASONRY BUILDINGS
5.1. SCOPE
Dimensioning and reinforcing of masonry buildings and building-like structures to beconstructed in seismic zones with load-bearing walls of natural or artificial materials, toresist both vertical and lateral loads shall be performed, along with currently enforced
relevant standards and codes, primarily in accordance with the requirements of thischapter. Requirements for masonry building foundations are given in Chapter 6.
5.2. GENERAL RULES
5.2.1 – Sliding stress on the walls of building which is generated by seismic loads definedby taking S (T1) = 2.5 and Ra (T1) = 2.5 according to Chapter 2, shall be calculated and it
shall be provided not to exceed permitted limit values.
5.2.2 – With the exception of the case given in 5.6.2 below, number of stories permitted
for masonry buildings is given in Table 5.1 depending on seismic zones.
TABLE 10.1 – MAXIMUM NUMBER OF STORIES PERMITTED
Seismic Zone
Maximum number of Stories
1
2
2, 3
3
4
4
5.2.3 – Maximum number of stories given in Table 5.1 correspond to ground storey
plus the upper stories. Area of a penthouse built in addition to those stories can notexceed 25 % of gross area of building at foundation level. The penthouse whose storey
area is more than 25 % of gross area of the building shall be deemed to be a full storey. In
addition, a single basement may be built. In the case where more than a single basement
is constructed, maximum number of stories given in Table 5.1 shall be reduced by one. In
all seismic zones, masonry buildings with adobe walls can be constructed utmost single
storey without considering basement.
5.2.4 – Storey height of masonry buildings shall be utmost 3.0 m from one floor top
level to the other. In masonry buildings with adobe walls, storey height can not be morethan 2.70 m and basement height can not be more than 2.40 m if it exists.
5.2.5 – Load-bearing walls of masonry buildings shall be arranged in plan, as much as
possible, regularly and symmetric or nearly symmetric with respect to the main axes.
Construction of partial basement shall be avoided.
5.2.6 - In plan, load-bearing walls shall be constructed so as to be placed one over theother.
5.3. ANALYSIS OF STRESS OF MASONRY WALLSIt shall be indicated that pressure and sliding stresses to be developed under the effect ofvertical loads and seismic analysis loads to be calculated by the method given in thissection do not exceed pressure and sliding stresses permitted according to type of masonrywall used in walls. If the stresses are exceeded, a new calculation shall be made byincreasing structural solid wall areas. Calculation of stress shall not be made for masonrybuildings with adobe walls.
87

5.3.1.1 – Because shear strength of walls is dependent on vertical stresses existing on thewalls, it is required to calculate stress of walls of masonry buildings under vertical loads.
5.3.1.2 – Comparison of pressure stresses generated on walls with stresses permitted
according to type of masonry wall shall be carried out. Loads coming from walls andfloorings shall be taken into account in this analysis. The stress to be derived by dividing
into cross section of the wall reduced as the cross sections of door and window spaces on
the wall shall not be more than the pressure stress permitted according to type of the wall.
5.3.2 – Pressure Safety Stress on Walls
This stress can be calculated by various methods given below:(a) 0.25 of wall strength calculated by pressure strength tests for wall particles made atequal strength as the pressure strength of masonnary unit and mortar to be used inconstruction of wall is the pressure safety stress.
(b) Wall safety stress can be taken from Table 5.2 depending on the mortar class used inwalls and the average free pressure strength of wall material given in TS – 2510.
(c) If strength test of wall particles is not made, 0.50 of free pressure strength obtained
experientially for the block used in wall is pressure strength of wall fd and 0.25 of thisstrength is the pressure safety stress fem of wall.
(d) If pressure strength of masonnary unit used in wall is not given or strength test of wall
is not made pressure strength stress for masonnary unit used in wall shall be taken from
Table 5.3.
5.3.2.1 – Pressure strengths of masonnary units and mortar used in wall shall be
determined by tests applied in accordance with concerned standards.
5.3.2.2 – Pressure strength stresses for walls shall be reduced by quantities given in Table
5.4 according to slenderness rates of walls.
TABLE 5.2 – PRESSURE SAFETY STRESSES FOR WALLS DEPENDING ON
MORTAR CLASS AND FREE PRESSURE STRENGTH OF WALL MATERIAL
Average Free Pressure Strengthof Wall Material
(MPa)
25
16
11
7
5

Mortar Class Used in the Wall (MPa)
A
B
C
D
E
(15)
(11)
(5)
(2)
(0.5)
1.8
1.4
1.2
1.0
0.8
1.4
1.2
1.0
0.8
0.7
1.0
0.9
0.8
0.7
0.6
0.8
0.7
0.7
0.6
0.5
0.6
0.5
0.5
0.4
0.4

88

TABLE 5.3 – PRESSURE SAFETY STRESSES OF WALLS IN WHICH FREE
PRESSURE STRENGTH IS UNKNOWN
Type of Masonnary Unit and Mortar
Pressure Safety Stress of Wall
Used in the Wallfem (MPa)
Vertical hallow block brick (hallow rate isless than 35 %, with lime mortar supported
1.0with cement)
Vertical hallow block brick (hallow rate isin between 35 – 45 %, with lime mortar
0.8
supported with cement)
Vertical hallow block brick (hallow rate ismore than 45 %, with lime mortar
0.5
supported with cement)
Filled block brick or clay brick (with lime
0.8
mortar supported with cement)
Stone wall (with lime mortar supported
0.3
with cement)Gas concrete (with adhesive)
0.6
Filled concrete briquette (with cement
0.8
mortar)TABLE 5.4 – REDUCING COEFFICIENTS FOR SAFETY STRESSESACCORDING TO SLENDERNESS RATE
Slenderness rate
6
8
10
12
14
16
18
20
22

Reducing
coefficient

1.0

0.95

0.89

0.84

0.78

0.73

0.67

0.62

0.56

24
0.51

5.3.3. Calculation of Sliding StressCalculation of sliding stresses generated parallel to horizontal joints of walls by seismic
design load shall be made as explained in this chapter.

5.3.3.1 – Relative sliding rigidity of solid wall parts rest among door or window spaces ineach axis of masonry building shall be calculated by the expression k A / h. In here, A ishorizontal cross section of solid wall part and h is the smallest of heights of spaces at both
two sides of solid wall part. If cross section of the wall is rectangular k = 1.0, if the wall
has an end element or there is a grinder or stay wall perpendicular to the wall on the edgeof the wall k = 1.2 shall be taken.
5.3.3.2 – Sliding rigidity of a wall axis is the sum of sliding rigidities of wall parts on thisaxis. Center of sliding rigidity of building shall be calculated by using sliding rigidity ofwall axes.
5.3.3.3 – Shear force on walls shall be calculated in the direction of both orthogonal axesof the building by considering storey torsion moment as well as storey shear force.
5.3.3.4 – Sliding stress developed on the wall shall be calculated by dividing seismic force
on the wall into horizontal cross section area of the wall and it shall be compared withsliding safety stress of wall em.
(5.1)
τem = τo + µσ

89

In this equation em = sliding safety stress of wall (MPa), o = cracking safety stress of wall(MPa), µ = coefficient of friction (it can be taken as 0.5) and σ is vertical wall stress(MPa). Cracking safety stress of wall, o, shall be taken from Table 5.5 according to typeof masonnary unit used in the wall.

TABLE 5.5 – CRACKING SAFETY STRESS OF WALLS
Cracking Safety Stress ofType of Masonnary Unit and Mortar Used in the
Wall
Wall τo (MPa )Vertical hallow block brick (hallow rate is less than 35
0.25%, with lime mortar supported with cement)
Vertical hallow block brick (hallow rate is more than
0.12
35 %, with lime mortar supported with cement)
Solid block brick or clay brick (with lime mortar
0.15
supported with cement)
Stone wall (with lime mortar supported with cement)
0.10
Gas concrete (with adhesive)
0.15
Solid concrete briquette (with cement mortar)
0.20
5.3.4. Elasticity Module
Elasticity Module (Ed) of masonnary units used in wall construction shall be calculated by
Equation (5.2).
(5.2)
Ed = 200 f d

5.4. LOAD – BEARING WALLS
5.4.1. Materials of Load – Bearing Walls
5.4.1.1 – Natural stone, solid brick, bricks and block bricks with hole ratios which are notexceeded the maximum void ratios permitted in TS – 2510 and TS EN 771 – 1 as materialof load – bearing walls, structural materials and elements of gas concrete, lime sandstone,
solid concrete blocks, adobe or similar masonnary units may be used as masonry materials
in the construction of load – bearing walls in accordance with Turkish Standards.
5.4.1.2 – Concrete blocks with holes, light aggregated concrete masonnary units,
bricks and block bricks with hole ratios which are exceeded the maximum void ratios
permitted in TS – 2510 and TS – 705 (TS EN 771 – 1) as material of load – bearing walls,
other bricks manufactured for infill walls in accordance with TS - 4377 and similarly
formed blocks shall never be used as load-bearing wall material.
5.4.1.3 – Natural stone load-bearing walls shall be used only in the basement and groundstories of masonry buildings.
5.4.1.4 – Concrete load-bearing walls shall be used only in the basements of masonrybuildings.
5.4.2. Strength of Wall Materials
5.4.2.1 – Strength and other specialties of natural and artificial masonnary units used inconstruction of walls and of mortars connecting those shall be as follows. These
conditions are not valid for adobe. Adobe can only be used in adobe buildings.

90

5.4.4.2 – According to gross pressure area, minimum pressure strength of naturaland artificial masonnary units to be used in load – bearing walls shall be 5.0 MPa atleast. Pressure strength of natural stones to be used in basement stories shall be 10.0
MPa at least. In the case where concrete walls are constructed in basements, minimum
quality of concrete to be used shall be C16.
5.4.2.3 – Lime mortar supported with cement (cement / lime / sand volumetric ratio =1 / 2 /9) or cement mortar (cement/sand volumetric ratio = 1 / 4) shall be used in load– bearing walls or cement mortar.
5.4.2.4 – Pressure safety stress of walls (fem) shall be calculated by using one of themethods given in 5.3.2.
5.4.2.5 – Sliding safety stress of walls shall be calculated according to Equation (5.1).
5.4.3. Minimum Thickness of Load-Bearing Walls
The minimum thicknesses of load-bearing walls, excluding plaster thicknesses, are given
in Table 5.6 depending on the number of stories in masonry building. In the case of nobasement, minimum wall thicknesses given in the Table 5.6 shall be valid for groundstorey and upper stories. In penthouses permitted in accordance with 5.2.3, wall
thickness specified for the storey below shall be applied.

TABLE 5.6 – MINIMUM THICKNESSES OF LOAD – BEARING WALLS
NaturalOthersConcrete Brick and Gas
Permitted
Seismic Zone
Stone
Stories(mm)
concrete
(mm)
(mm)
500
250
1
200
1, 2, 3 and 4 Basement storey
Ground storey
500
1
200
Basement storey
500
250
1.5
300
500
1
200
1, 2, 3 and 4 Ground storey
First storey
1200
Basement storey
500
250
1.5
300
Groundstorey500
1.5
300
2, 3 and 4First storey
1200
Second storey
1200
Basement storey
500
250
1.5
300
Ground storey
500
1.5
300
First
storey1.53004Second storey
1
200
Third storey
1
200

5.4.3.1 – In buildings with adobe walls, external load – bearing walls shall be at least

1.5 brick size, whereas internal adobe load-bearing walls shall be at least 1 brick size.
Nominal adobe brick dimensions to be used in load – bearing walls shall be 120 x 300 x
400 (main) and 120 x 190 x 400 (lamb) or 120 x 250 x 300 (main) and 120 x 180 x 300(lamb) in mm’s.

5.4.4. Total Length Limit for Load – Bearing Walls
The ratio of the total length of masonry load-bearing walls in each of the orthogonal
directions in plan (excluding window and door openings), to gross floor area (excluding91

cantilever floors) shall not be less than (0.2 I) m/m2 where I, represents Building
Importance Factor defined in Chapter 2.

2
d / A ≥ 0. 2 I m / m

Earthquake direction

d: Length of hatched area (m)2

A: Gross floor area (m )I: Building importance factor (Chapter 2)

Figure 5.1
5.4.5. Maximum Unsupported Length of Load-Bearing Walls
5.4.5.1 – Unsupported length of any load-bearing wall between the load – bearing wallaxes in the perpendicular direction in plan shall not exceed 5.5 m. in the first seismic zone
and 7.5 m in other seismic zones. Maximum unsupported length of wall in masonrybuildings with adobe walls shall be 4.5 m.
5.4.5.2 – In the case the condition given in 5.4.5.1 above is not satisfied, reinforced
concrete vertical bond beams shall be constructed along the full storey height at thecorners of building and in walls with axis to axis spacing in plan not more than 4.0 m.
However unsupported length of such walls shall not be more than 16 m (Figure 5.2).

91
92

ℓ2

ℓ1

Unsupported wall length: 1, 2 and 3(See 5.4.5.1)≤ 4.0 mVertical bondBeam

Vertical bondBeam
≤ 16.0 mℓ3≤ 5.5 m (1st Seismic zone)≤ 7.0 m (2nd, 3rd and 4th seismic zones)≤ 4.0 mVertical bond
Beam

Figure 5.2
5.4.6. Openings in Load-Bearing Walls
The following rules shall be followed in openings to be provided in load – bearing walls(Figure 5.3):

5.4.6.1 – Plan length of the solid wall segment to be set between the corner of a building
and the nearest window or door opening to the corner shall not be less than 1.50 m in thefirst and second seismic zones and 1.0 m in the third and fourth seismic zones. Thisquantity shall be at least 1.0 m in buildings with adobe walls in all seismic zones.
5.4.6.2 – Excluding the corners of buildings, plan lengths of the solid wall segments
between the window and door openings shall not be less than 1.0 m in the first and second
seismic zones and 0.8 m in the third and fourth seismic zones. This quantity shall be atleast 1.0 m in buildings with adobe walls in all seismic zones.
5.4.6.3 – In the case where reinforced concrete vertical bond beams according to 5.5.3 aremade on both sides of the window and door openings, condition of minimum lengths ofwall segments given in 5.4.6.1 and 5.4.6.2 may be decreased by 20%. If two timber pillars
with section of 0.10 m x 0.10 m are set on both two sides of the window and door
openings, solid wall segment between two openings may be 0.80 m in buildings with
adobe walls. These timber pillars shall be connected to the timber bond beams of window
and door.
5.4.6.4 – Excluding the corners of buildings, plan length of a solid wall segment between
intersection of the walls and the nearest window or door opening to the intersection of theorthogonal walls shall not be less than 0.50 m in the all seismic zones. In case where
reinforced concrete vertical bond beams according to 5.5.3 are exist on both sides of the
openings along the height of the storey solid wall segment may be less than 0.50 m.
5.4.6.5 – Plan length of each window or door opening shall not be more than 3.0 m. In
buildings with adobe walls, door openings shall not be more than 1.0 m in horizontal axis
and 1.90 m in vertical axis; window openings shall not be more than 0.90 m in horizontal
axis and 1.20 m in vertical axis.
93

5.4.6.6 – Total plan lengths of window or door openings along the unsupported lengthof any wall defined in 5.4.5 shall not be more than 40% of the unsupported wall
length.
5.4.6.7 – In the case where reinforced concrete vertical bond beams according to 5.5.3 aremade on both sides of the window or door openings, the maximum length of
openings defined in 5.4.6.6 and the maximum ratio of openings defined in 5.4.6.5 may be
increased by 20%. This condition is not valid for buildings with adobe walls.
1.5 m
1.0 m

1st and 2nd Seismic Zone
3rd and 4th Seismic Zone

1.0 m
0.8 m

ℓb1

≥ 0.5 mℓb2

ℓb1 ve ℓb2 ≤ 3.0 m(ℓb1 + ℓb2) ≤ 0.40 ℓnℓn (Unsupported wall length)

Figure 5.3
5.5. LINTELS AND BOND BEAMS
5.5.1. Lintels
5.5.1.1 – Each of seating lengths of window and door lintels on the walls shall not be lessthan 15% of lintel clear span and less than 200 mm.
5.5.1.2 – Cross sections dimensions of lintels as well as longitudinal transverse
reinforcement shall not be less than the values given in 5.5.2.1 for horizontal bond beams.
5.5.1.3 – Timber lintel may be set over and under the window and door in buildings with
adobe walls. Timber lintels shall be made with two square timbers with section of 100 mm
x 100 mm. Each of seating lengths of timber lintels on the walls shall not be less than 200
mm.
5.5.2. Horizontal Bond Beams
5.5.2.1 – Reinforced concrete horizontal bond beams satisfying the following
conditions shall be made at places where each of the slabs, including stair landings, issupported by structural walls such that they shall be cast (monolithically) with thereinforced concrete slabs.
(a) Width of horizontal bond beams shall be equal to the width of wall, and their height
shall not be less than 200 mm.
(b) Concrete quality for bond beams shall be at least C 16, Ø 8 hoops with a maximum
spacing of 250 mm shall be set with together longitudinal reinforcement at least 6Ø10
on stone walls with three at the bottom and three at the top, and at least 4 Ø10 on otherload – bearing walls. Longitudinal rebars shall be appropriately overlapped at the corners
and intersections to achieve continuity (Figure 5.4).
94

5.5.2.2 – In rubble stone walls, reinforced concrete bond beams shall be madeexcluding the slab and stair landing levels in accordance with the rules given in 5.5.2.1
with vertical axis to axis spacing not more than 1.5 m.
5.5.2.3 – Timber bond beams may be made in adobe masonry walls. Timber bond beams
shall be tar emulsified two elements of square sections of 10 cm x 10 cm which are to beplaced with outer faces coinciding with the exterior and interior wall surfaces. These
pieces shall be tied each other at every 50 cm with nail jointed timber elements ofcross section of 5 cm x 10 cm and holes in between shall be filled with stone aggregate.

≤ 250 mmØ8
≥ 40Ø≤ 250 mm≥ 40Ømin Ø10≤ 250 mm

Ø8

≥ 40Ø

≤ 250 mmmin Ø10Figure 5.4

955.5.3. Vertical Bond Beams
5.5.3.1 – In order to enhance the earthquake resistance of masonry buildings, it shall beappropriate to construct reinforced concrete vertical bond beams in full storey height on
the corners of buildings, along the vertical intersections of the load – bearing walls and on
both sides of the door and window openings.
5.5.3.2 – Vertical bond beams shall be constructed by reinforcing and concreting thesection in between the formworks to be placed parallel to the walls, following theconstruction of load – bearing walls on both sides (Figure 5.5).
5.5.3.3 – Cross section dimensions of vertical bond beams shall be equal to thicknesses ofwalls intersecting at corners of the buildings and at the intersections of the load – bearing
walls. In vertical bond beams to be constructed on both sides of window and door
openings, cross section dimensions of the bond beam perpendicular to the wall shall not
be less than the wall thickness, whereas the other cross section dimension shall not be lessthan 200 mm.
5.5.3.4 – Concrete quality for vertical bond beams shall be at least C16, Ø8 hoops with amaximum spacing of 200 mm shall be set with together longitudinal reinforcement atleast 6Ø12 on stone walls with three parallel to both wall faces and at least 4Ø12 on otherload – bearing walls. Longitudinal starter bars shall be provided at the foundation and at
the intermediate floors for longitudinal rebars (Figure 5.5).
≥ 200 mm

≥ 200 mm

≥ 200 mmFigure 5.5
5.6 SLABS
5.6.1 – Floor slabs of masonry buildings shall be reinforced concrete plate slabs or joist
floors whose dimensions and reinforcements are designed in accordance with therequirements of TS-500.

96

5.6.2 – Masonry buildings with slabs other than those defined in 5.6.1 above, shall be
constructed in all seismic zones with maximum two stories excluding the basement, if
any. In such buildings, horizontal bond beams supporting the slabs shall also beconstructed in accordance with 5.5.2. Buildings with adobe walls shall be constructed withmaximum one storey excluding basement.
5.6.3 – Cantilever elements such as balconies, cornices and eaves of roofs shall be madeonly as an extension of floor slabs and the clear cantilever length shall not be more than
1.5 m. Clear cantilever length of cantilevered stairs shall be at most 1.0 m. This condition
is not valid for buildings with adobe walls.
5.7. ROOFS
5.7.1 – Roofs of the masonry buildings may be constructed as reinforced concrete terrace
roof, timber or steel truss roof bearing on roof slab.
5.7.2 – Connections of the timber roof elements to the roof slabs or to horizontal bondbeams on load – bearing walls shall be made in accordance with the rules given in TS –2510.
5.7.3 – In the case where the height of the end wall resting on the horizontal bond beam at
the top storey exceeds 2.0 m, vertical and inclined bond beams shall be constructed(Figure 5.6).
5.7.4 – Roofs of the buildings with adobe walls shall be constructed in a way not toexceed external walls at most 500 mm and to be as light as possible. Soil roof shall not bemade in first and second seismic zones. Soil cover thickness of soil roof shall not be morethan 150 mm in third and fourth seismic zones. Roofs of adobe buildings may beconstructed as timber spring or reinforced concrete plate.
Reinforced Concrete Bond
Beam

Figure 5.6

97

5.8. NON – BEARING WALLS
5.8.1 – Thickness of non-bearing partition walls shall be at least 1 0 0 m m . Such walls
shall be constructed by connecting to load – bearing walls on both edges along thevertical intersection. At least 10 mm gap shall be allowed between the top of the non –bearing walls and floor bottom of the top slab, however required measures shall be taken
in order to prevent the toppling of wall out – of – plane by the effect of seismic loads
perpendicular to its plane.
5.8.2 – Height of parapets on terraces made of masonry wall material shall not be morethan 600 mm. Required measures shall be taken in order to prevent toppling of suchparapets under the seismic loads.
5.8.3 – Height of garden walls made of masonry wall material shall not be more than
1.0 m from the pavement level.

98CHAPTER 6 – EARTHQUAKE RESISTANT DESIGN REQUIREMENTS FOR
FOUNDATION SOILS AND FOUNDATIONS
6.0. NOTATION= Effective Ground Acceleration Coefficient defined in Chapter 2.
= Equivalent lateral seismic coefficient used in calculation of the soil pressure= Equivalent vertical seismic coefficient used in calculation of the soil pressure= Total height of uniform soil deposit or sum of layer thicknesses in case oflayered soils
h1= Thickness of the topmost soil layerI= Building Importance Factor defined in Chapter 2.
i= Slope angle which the soil surface on the side of active or passive pressure
creates upwards with horizontal axis
Kas
= Static active pressure coefficientKad= Dynamic active pressure coefficientKat= Total active pressure coefficient
Kps= Static passive pressure coefficient
Kpd= Dynamic passive pressure coefficient
Kpt= Total passive pressure coefficient
Pad= Resultant of dynamic active pressure force due to soil mass
Ppd
= Resultant of dynamic passive pressure force due to soil masspad (z) = Variation function of dynamic active pressure due to soil mass with respect todepth
ppd (z) = Variation function of dynamic passive pressure due to soil mass with respect todepth
pv (z) = Variation function of vertical soil pressure with respect to depth
Qad= Resultant of dynamic active pressure force due to uniformly distributed
external load
Qpd
= Resultant of dynamic passive pressure force due to uniformly distributed
external loadqad (z) = Variation function of dynamic active pressure due to uniformly distributed
external load with respect to depth with respect to depth
qpd (z) = Variation function of dynamic passive pressure due to uniformly distributed
external load with respect to depthqo= Amplitude of uniformly distributed surcharge
Rza= Reduction factor used in determining the dynamic internal forces applicable tosection design of soil retaining wallsz= Depth measured downwards from free soil surface
zcd= Depth of the resultant of active or passive pressure force measured downwards
from soil surface layer= Angle of wall – soil interface with vertical towards active or passive pressureα= Friction angle between soil and wallδ
= Internal friction angle of soilϕ
= Rebar diameter∅γ= Dry unit volume weight of soil
= Submerged unit volume weight of soilγbγs= Saturated unit volume weight of soil
λ= An angle calculated for determining total active and passive pressure
coefficients in terms of equivalent seismic coefficients
Ao
Ch
Cv
H

99

6.1. SCOPE
Determination of soil conditions of new buildings to be constructed and existing buildings
to be enhanced in seismic zones; design of reinforced concrete, structural steel andmasonry building foundations and soil retaining structures shall be performed, alongwith the applicable codes and standards in relevant areas, primarily in accordance withthe rules and requirements of this chapter.

6.2. DETERMINATION OF SOIL CONDITIONS
6.2.1. Soil Groups and Local Site Classes
6.2.1.1 – Soil groups and local site classes to be considered as the bases of determinationof local soil conditions are given in Table 6.1 and Table 6.2, respectively. Values
concerning soil parameters in Table 6.1 are to be considered as standard values given for
guidance in determining the soil groups.
6.2.1.2 – Soil investigations based on required site and laboratory tests are mandatory for
below given buildings with related reports prepared and attached to design documents.
Soil groups and local site classes defined in accordance with Table 6.1 and Table 6.2
shall be clearly indicated in reports.
(a) All buildings with total height exceeding 60 m in the first and second seismic zones,(b) Irrespective of the building height, buildings in all seismic zones with Building
Importance Factor of I = 1.5 and I = 1.4 according to Table 2.3 of Chapter 2.
6.2.1.3 – Regarding the buildings outside the scope of above given 6.2.1.2, in the first andsecond seismic zones, it is mandatory to indicate available local information or
observation results to be used in determination of soil groups and local site classes inaccordance with the definitions in Table 6.1 and Table 6.2 or to quote publishedreferences relating this subject in the seismic analysis.
6.2.1.4 – In the first and second seismic zones, determination of horizontal bedding
parameters as well as horizontal and axial load carrying capacities of piles under seismic
loads in Group (C) and (D) soils according to Table 6.1 shall be carried out on thebasis of soil investigations including in – situ and laboratory tests.
6.2.2. Investigation of Liquefaction Potential
In all seismic zones, it is mandatory to investigate whether the Liquefaction Potential
exists in Group (D) soils according to Table 6.1, by using appropriate analysis methods
based on in – situ and laboratory tests in the cases the ground water level is less than 10 mfrom the soil surface and to document these results.

100

TABLE 6.1 - SOIL GROUPS
Soil
Group

(A)

(B)

(C)

(D)

Description of
Soil Group

Standard
Penetration(N/30)

1. Massive volcanic rocks,
unweathered soundmetamorphic rocks, stiff
cemented sedimentary rocks
2. Very dense sand, gravel...
> 50
3. Hard clay and silty clay… > 32
1. Soft volcanic rocks such as
tuff and agglomerate,
weathered cemented
sedimentary rocks withplanes of discontinuity……
2. Dense sand, gravel.......... 30 50
3. Very stiff clay, silty clay… 16 32
1. Highly weathered soft
metamorphic rocks andcemented sedimentary rocks
with planes of discontinuity
2. Medium dense sand andgravel......…………………. 10 30
3. Stiff clay and silty clay..... 8 16
1. Soft, deep alluvial layerswith high ground water level
2. Loose sand.................…..
< 10
3. Soft clay and silty clay…..
<8

Relative
Density
(%)

85

65

35

Unconfined.
Compressive
Strength(kPa)

Drift Wave
Velocity(m / s)> 1000> 1000
> 700
> 700

100

85

65

> 400

400

700
400
300

1000
700
700

< 500

400

700

200

200
200

400
300

500

1000

200

100

< 35

< 100

< 200
< 200
< 200

TABLE 6.2 - LOCAL SITE CLASSES

Local Site
Class
Z1
Z2
Z3
Z4

Soil Group according to Table 6.1 andTopmost Soil Layer Thickness (h1)Group (A) soils
Group (B) soils with h1 ≤ 15 m
Group (B) soils with h1 > 15 m
Group (C) soils with h1 ≤ 15 m
Group (C) soils with 15 m < h1 ≤ 50 m
Group (D) soils with h1 ≤ 10 m
Group (C) soils with h1 > 50 m
Group (D) soils with h1 > 10 m

101

NOTES ON TABLE 6.2:(a) In the case where the thickness of the topmost soil layer under the foundation base isless than 3 m, the layer below may be considered as the topmost soil layer
indicated in Table 6.2.
(b) In the case where the foundation system is comprised of vertical piles or piles with aslope of 1 / 6 or less inclined with respect to vertical, the topmost soil layer indicated inTable 6.2 may be deemed to be the layer at the lower tip of the shortest pile. However insuch a case, it is essential to take piles into account as structural elements together withthe superstructure in the seismic analysis to be performed in accordance with Chapter 2,
or to idealize horizontal and vertical pile rigidities with equivalent springs under the pile
caps. By considering group effect in the analysis, rigidity and inertia properties of pilecaps and tie beams together with horizontal and vertical bedding of piles to the soil (soil– pile interaction).
(c) In cases where conditions given in paragraph (b) above are not applied or pile
inclination with respect to vertical exceeds 1 / 6 in the third and fourth seismic zones inaccordance with 6.3.3.1, the topmost soil layer indicated in Table 6.2 shall be taken as
the first layer under the pile caps.
6.3. RULES AND REQUIREMENTS FOR FOUNDATIONS
6.3.1. General Rules
Building foundations shall be constructed on the bases of principles of soil mechanics andfoundation construction, by considering the properties of underlying soils such that any
damage in the superstructure due to settlements or differential settlements during
earthquake is avoided. Rules given in this chapter for foundations are applicable to thefoundations of reinforced concrete, structural steel and masonry buildings.

6.3.2. Soil Safety Stresses and Safety Ultimate Load of Piles
6.3.2.1 – Soil safety stress and safety ultimate load of pile for horizontal and axial loads infoundations with pile specified with respect to static loads may be increased in the case of
seismic loading by at most 50 % for foundation soils classified as Group (A), (B) and (C)in Table 6.1.
6.3.2.2 – Soil safety stress and safety ultimate load of piles shall not be increased in thecase of seismic loading for foundation soils classified as Group (D) in Table 6.1.
6.3.3. Requirements for Piled Foundations
6.3.3.1 – Inclined piles with more than 1 / 6 inclination with respect to vertical shall not be
used in the first and second seismic zones.
6.3.3.2 – Piled foundations shall be analyzed with respect to earthquake induced lateralloads and effects in addition to axial loads.

1026.3.3.3 – In the first and second seismic zones, longitudinal reinforcement ratio of cast –in – situ cased or uncased bored piles shall not be less than 0.008 within the top 1 / 3 ofthe pile length under the pile cap, which shall not be less than 3 m. Diameter ofspiral reinforcement to be provided within this zone shall not be less than 8 mm
and the pitch of spirals shall not be more than 200 mm, however pitch of spirals
shall be reduced to 100 mm within a length of at least twice the pile diameter from the top
6.3.3.4 – Longitudinal reinforcement ratio of reinforced concrete prefabricated driven
piles shall not be less than 0.01. In the first and second seismic zones, diameter oftransverse reinforcement within the top 1 / 3 of the pile length under the pile cap shall not
be less than 8 mm. Hoop spacing or pitch of spirals within this length shall not be morethan 200 mm, however hoop spacing pitch of spirals shall be reduced to 100 mm within alength of at least twice the pile diameter top (twice the greatest dimension of piles withrectangular cross-section) from the from the top. Transverse reinforcement requirements
shall be equally applicable to pre – stressed prefabricated driven piles.
6.3.4. Foundation Tie Beams
6.3.4.1 – In reinforced concrete and structural steel buildings, tie beams shall be
provided to connect individual foundations or pile caps in both directions or toconnect continuous foundations at column or structural wall axes. Tie beams may beomitted or their numbers may be reduced on foundation soils classified as Group (A) in
Table 6.1.
6.3.4.2 – Consistent with the foundation excavation, tie beams may be constructed at any
level between the bottom of the foundation and the bottom of the column.
6.3.4.3 – The minimum requirements to be satisfied by tie beams are given in Table 6.3
depending on the seismic zone of the building and the soil groups defined in Table 6.1.
TABLE 6.3 – MINIMUM REQUIREMENTS FOR TIE BEAMSDESCRIPTION OF
REQUIREMENT

Seismic
Zone

1. Minimum axial force oftie beam (*)
2. Minimum cross – section
dimension (mm) (**)
3. Minimum cross-section
area (mm2)4. Minimum longitudinal
reinforcement

1, 2
3, 4
1, 2
3, 4
1, 2
3, 4
1, 2
3, 4

Soil
Group
(A)
6%
4%
250
250
62500
62500
4∅14
4∅14

Soil
Group
(B)
8%
6%
250
250
75000
62500
4∅16
4∅14

Soil
Group
(C)
10 %
8%
300
250
90000
75000
4∅16
4∅16

Soil
Group
(D)
12 %
10 %
300
250
90000
75000
4∅18
4∅16

(*)

As a percentage of the greatest axial force of columns or structural walls tie beams areconnected to.
(**)
The minimum cross – section dimension shall not be less than 1/30 of the clear span of
the tie beam.

1036.3.4.4 – Tie beams shall be considered in the section design as resisting against bothpressure and tension forces. In the case of resistance against pressure, buckling effectmay be neglected in tie beams confined by soil or floor concrete. In the case of tension,
it shall be considered that tension forces are resisted by only reinforcement. Hoop
diameter of tie beams shall not be less than 8 mm and their spacing shall not be more than
200 mm.
6.3.4.5 – Tie beams may be replaced by reinforced concrete slabs. In such a case slab
thickness shall not be less than 150 mm. It shall be demonstrated by calculation that theslab and its reinforcement safely transfer the forces equal to those given for tie beams inTable 6.3.
6.3.5. Under – Wall Foundations of Masonry Buildings
6.3.5.1 – Foundations of masonry buildings shall be constructed as reinforced concrete
under – wall foundations under the load bearing walls. Depth of an under – wall
foundation shall be determined by considering the soil characteristics, ground water level
and the local frost depth. In buildings without basement, top level of stone or concrete
walls to be constructed on the foundations shall be at least 0.50 m above thepavement level.
6.3.5.2 – Concrete quality of under – wall foundations shall be at least C16.
Requirements on the dimensions and the reinforcement of under – wall foundations are
given in Table 6.4 depending on the soil groups defined in Table 6.1.
6.3.5.3 – Foundations may be constructed with steps on sloped ground made ofsoils classified in Table 6.1 as Group (A), (B) or (C). Requirements for steppedfoundations are also given in Table 6.4.
6.3.5.4 – Lateral spacing between the longitudinal rebars to be placed under – wall
foundations shall not exceed 0.30 m at the top and bottom; appropriate overlapping shallbe provided to achieve continuity at corners, junctions and in stepped foundations.
TABLE 6.4 – REQUIREMENTS FOR UNDER – WALL FOUNDATIONS

Soil
Soil
Soil
Group Group Group(A),(B)(C)(D)
Minimum foundation width (mm)
500
600
700
Shoe width (from both sides) to be added to wall thickness (mm) 2 x 150 2 x 200 2 x 250
Minimum foundation height (mm)
300
400
400
Minimum longitudinal reinforcement at the top and bottom
3∅12
3∅14
4∅14
Minimum hoop at foundations∅8 / 30 ∅8 / 30 ∅8 / 30
Minimum lateral spacing of steps (mm)
1000
1500
Minimum step overlapping length (mm)300
400
Maximum step height (mm)300
300
DESCRIPTION OF REQUIREMENT

104

6.4. SEISMIC SOIL PRESSURES AND SOIL RETAINING STRUCTURES
6.4.1. Total Active and Passive Pressure Coefficients
6.4.1.1 – Total Active Pressure Coefficient, Kat, and Total Passive Pressure
Coefficient, Kpt, which shall be used to calculate the sum of static soil pressure andadditional dynamic soil pressure induced by earthquake are given by Equation (6.1), by
neglecting the soil cohesion in order to remain on the conservative side.
(1 ± Cv ) cos 2 (ϕ − λ − α)sin(ϕ + δ) sin(ϕ − λ − i )K at =
1+
2
cos(δ + α + λ ) cos(i − α)cosλ cos α cos(δ + α + λ)

(1 ± Cv ) cos 2 (ϕ − λ + α)sin(ϕ + δ) sin(ϕ − λ + i )K pt =
1−
2
cos(δ − α + λ) cos(i − α)cosλ cos α cos(δ − α + λ)−2

(6.1a)−2(6.1b)

6.4.1.2 – The angle λ in Equation (6.1) is defined by Equation (6.2).
(a) For dry soils,
Ch(1 ± Cv )(6.2a)γsCh
γ b (1 ± Cv )(6.2b)

λ = arctan(b) For submerged soils,

λ = arctan

6.4.1.3 – In the case of submerged or saturated soils, δ in Equation (6.1) shall be
replaced by δ/2.
6.4.1.4 – Equivalent lateral seismic coefficient, Ch, appearing in Equation (6.2) isdefined by Equation (6.3).
(a) In soil retaining structures behaving as vertical free cantilevers,
Ch = 0.2 (I + 1) Ao(6.3a)(b) In soil retaining structures and elements horizontally supported by building floors orsoil anchors,(6.3b)
Ch = 0.3 (I + 1) Ao105

6.4.1.5 – Equivalent vertical seismic coefficient, Cv, appearing in Equation (6.1) andEquation (6.2) is defined by Equation (6.4). However, it shall be Cv = 0 in basement
walls which are horizontally supported by building floors.
Cv =

2C h
3

(6.4)

The cases + Cv or − Cv shall be considered as consistent with Equation (6.2) to yield more
unfavorable lateral soil pressure by Equation (6.1).

6.4.2. Dynamic Active and Passive Soil Pressures
6.4.2.1 – Dynamic active pressure coefficient, Kad, and dynamic passive pressure
coefficient, Kpd, induced by earthquake shall be determined by Equation (6.5).
Kad = Kat − Kas
Kpd = Kpt − Kps(6.5a)(6.5b)

Static active pressure coefficient, Kas, and static passive pressure coefficient, Kps,
appearing in Equation (6.5) may be obtained by substituting λ = 0 and Cv = 0 in Equation(6.1).

6.4.2.2 – Variation of dynamic active and passive soil pressures along the depth of soil
which is induced by soil mass in addition to static soil pressure in case of earthquake
which are induced in addition to static soil pressure by the soil mass during earthquake,is defined by Equation (6.6).
pad (z) = 3 Kad (1 − z / H) pv (z)ppd (z) = 3 Kpd (1 − z / H) pv (z)(6.6a)(6.6b)In the special case of uniform and dry soil, the positive value of the resultant Pad ofdynamic active soil pressure and the negative value of the resultant Ppd of dynamic
passive soil pressure which are induced in addition to static soil because of earthquakeand zcd which indicates the depths of such resultants measured from the top soil level, areobtained as given by Equation (6.7) and Equation (6.8), respectively, by integrating
Equation (6.6) along the soil depth by taking pv (z) = γ z:
Pad = 0. 5 γ Kad H2
Ppd = 0. 5 γ Kpd H2(6.7a)(6.7b)

zcd = H / 2(6.8)

In the case of submerged soil, γb shall be considered in lieu of γ in determining pv (z)and hydrodynamic pressure of water shall not be calculated additionally. In the case ofsaturated soil, γs shall be used in lieu of γ.

6.4.2.3 – Variation of dynamic active and passive pressures along the depth of soil
which are induced in addition to static soil pressure by uniformly distributed externalloads in case of earthquake, are defined by Equation (6.9).
qad (z) = 2 qo Kad (1 − z / H) cos α / cos (α − i)(6.9a)

106

qpd (z) = 2 qo Kpd (1 − z / H) cos α / cos (α − i)

(6.9b)In the case where soil characteristics are uniform, the resultants Qad and Qpd of active(positive) and passive (negative) soil pressures which are induced in addition to static soilpressure by contribution of earthquake and zcd which indicates the depths of such
resultants measured from the top soil level, are obtained as given by Equation (6.10) andEquation (6.11), respectively, by integrating Equation (6.9) along the soil depth.
Qad = qo Kad H cos α / cos (α − i)
Qpd = qo Kpd H cos α / cos (α − i)(6.10a)(6.10b)zcd = H / 3(6.11)

6.4.3. Dynamic Soil Pressures in Layered Soils
Expressions given above by Equation (6.6) and Equation (6.9) can be applied also forcase of layered soils. In such a case, the coefficients Kad or Kpd pertinent for the layer
concerned shall be used and the depth z shall always be measured downwards from thefree soil surface. Resultants of dynamic active or passive pressures of each layer and theirdepths within the layer may be obtained by integrating Equation (6.6) and Equation (6.9)
along the depth of the relevant layer.

6.4.4. Requirements for Soil Retaining Structures
6.4.4.1 – In the analysis performed by considering dynamic soil pressures given by
Equation (6.6) and Equation (6.9) in addition to static soil pressures and inertia forces ofthe structure which acts on its self mass, safety factor against sliding shall be taken at least
1.0 and safety factor against overturning shall be taken at least 1.2.
6.4.4.2 – Internal forces to be taken into account in the section design of reinforced
concrete soil retaining walls and reinforced concrete or steel sheet pile walls shall be thoseobtained by dividing the internal forces calculated according to the dynamic soil pressures
given in Equation (6.6) and Equation (6.9) into the coefficient Rza = 1.5, in addition tointernal forces induced by static soil pressures. It may be taken Rza = 2.5 for temporary
steel sheet pile walls.

107

CHAPTER 7 – EVALUATION AND INVIGORATE OF THE EXISTINGBUILDINGS
7.0. NOTATION
Ac
a1(i)

=
=

b
bw
d
d1(i)

=
=
=
=

d1(p)
(EI)e
(EI)o
fcm
fctm
fyw
Hw

=
=
=
=
=
=
=

h
hwall
hji
hk
Lp

Mx1

=
=
=
=
=
=
=
=

Nd

=

Nk

=

Ra
r
rs
s
Sdi1
tj
u(i)xN1

=
=
=
=
=
=
=

wall
w

u(p)xN1 =
Ve

=

Vj
Vr
V(i)x1

=
=
=

cg

=

Gross section area of column or wall end zone
Modal acceleration belonging to the first mode made in the end of the (i)’th
drive step
Width of the horizontal plate in steel spiral.
The body width of the cross section
Effective beam and column height
Modal displacement belonging to the first mode obtained at the and end of (i)’th
impulse step.
Modal displacement request belonging to the first mode.
Effective deflection rigidity of the cracked cross section.
Deflection rigidity of the cracked cross section
Strength of the existing concrete defined according to 7.2
Tensile strength of the existing concrete defined according to 7.2
Outflow strength of the steel in steel spiral.
Total height of partition measured from under the foundation or from theground floor
Column cross section dimension in the working direction
Height of the filling wall
Storey height of the j’th column or curtain in i’th storey
Length of the column
Size of plastic joint
Height of filling wall
Length of partition or piece of strap partition on plan
Effective mass belonging to first (prevalent) defined for linear elastic
behavior in the x earthquake direction
Factored axial force calculated under simultaneous action of vertical loads
and seismic loads
Axial force correspond to moment capacity calculated with the existing
reinforcement strength defined according to 7.2.
Inhibition Coefficient of the Power of Earthquake
Ratio of exposure/capacity
The limit value of ratio of exposure/capacity
Space between horizontal plates in steel spiral.
Non-linear spectral displacement belonging to first mode
Thickness of the horizontal plates in steel spiral.
Displacement belonging to first mode obtained from the end of the i’th
impulse step in the direction of (x) earthquake at the top of the building (N’thstorey)Top displacement request in the direction of (x) earthquake at the top of thebuilding (N’th storey)
Shear force taken into account for the calculation of transverse reinforcement ofcolumn, beam or wall
Additional shearing strength provided with steel spiral.
Shearing strength of the column, beam and curtain cross section
Base shearing force belonging to first mode (prevalent mode) obtained at theend of I’th impulse step in direction of x earthquake
Deformation of concrete pressure unit in the outermost fibrous of the section
inside of the lateral reinforcement binders.

108

cu
s
p
t
y

=
=
=
=
=

ρ
ρb
ρs

=
=
=
=
=
=
=
=

ρsm

=

ρ’
we

=
=

xN1
x1

ηbi
p

Deformation of concrete pressure unit in the outermost fibrous of the sectionof the cross section
Deformation of reinforcement steel unit
Plastically curvature request
Total curvature request
Mode figure width in the direction of (x) earthquake at the top of thebuilding (N’th storey)
Coefficient of the Level of Torsion defined in I’th storey
Additive factor belonging to first mode in the direction of x earthquake
Torsionally Irregularity Factor defined at i’th storey of building
Equivalent Earthquake Power Derogation Factor
Plastic drift volition
Tension reinforcement ratio
Balanced reinforcement ratio
Volumetric ratio of spiral reinforcement which are exist in the cross section andarranged as “special seismic hoops and crossties” according to 3.2.8
Volumetric ratio of the transverse reinforcement necessary to be existed in the crosssection according to 3.3.4, 3.4.4
Pressure reinforcement ratio
Width of polymer ribbon with fiber.

109

7.1. SCOPE
7.1.1 – Rules of calculation to be used in the assessment of performances of the existingbuildings and building - type structures in earthquake zones under the impact of anearthquake, principles to be followed in decisions of strengthening, and principles of design
for strengthening for buildings that decision of strengthening is made are defined in thissection.
7.1.2 – Calculation methods and assessment essentials given in this section do not apply tosteel and masonry buildings. However, the existing data regarding the existing steel andmasonry buildings will also be collected in this section. Calculations and assessment forexisting and strengthened steel buildings will be carried out according to the essentials for
newly built structures defined in Sections 2 and 4. Calculations and assessment for existingand strengthened masonry buildings will be carried out within the frame of the essentials
defined in Section 5.
7.1.3 – The existing prefabricated reinforced concrete buildings can be assessed according
to the rules given in Sections 2 and 3, or else, 7.6 can be used for the determining of theperformances of these buildings. However, rules of 3.12 will prevail for the assessmentof the confinement zones.
7.1.4 – Rules given in this section do not apply to non-building-type structures mentioned in
2.12. Furthermore, assessment and strengthening of registered buildings with historical andcultural value and monuments are outside the scope of this Regulation.
7.1.5 – Earthquake performance of damaged buildings following an earthquake causing
damage in the building cannot be determined with the methods given in this section.
7.1.6 – To Strengthen a damaged building following an earthquake causing damage in thebuilding, and then to determine the earthquake performance of the strengthened building,essentials given in this section shall be used. The civil engineer responsible for the projectwill decide in what extent the strength and rigidity of the existing elements of the damagedbuilding will be taken into consideration when strengthening the damaged building.
7.2. DATA COLLECTION FROM BUILDINGS
7.2.1. Scope of Data to Be Collected from Buildings
7.2.1.1 – Data regarding the details and sizes of the elements to be used in determining thecapacities of the elements of the supporting systems of the existing buildings andinformation regarding the geometry and material characteristics of the supporting systems
will be achieved from the projects and reports of such buildings, from observations andmeasurements to be carried out on the building, and from trials performed on the material
samples taken from the building.
7.2.1.2 – The procedures to be performed in the scope of data collection from buildings aredefining of the structural system, determining the geometry, foundation system and groundproperties of the building, determining the existing damage, if any, and / or repairs,
measuring the dimensions of the elements, determining the material characteristics, andchecking the compliance of all these data with the project of the building, if any.

110

7.2.1.3 – The procedures of examination, data collection and arrangement, assessment,material sample collection, and trials within the scope of data collection from buildings shallbe performed under the responsibility civil engineers.
7.2.2. Levels of information
According to the scope of the data obtained from the examination of the buildings
concerning the existing situation, information level for each building type, andconsequently, the information level coefficients mentioned in 7.2.16 shall be completed.
Information levels shall be classified as limited, medium, and comprehensive, respectively.
Information level shall be used for the calculations of capacities of supporting elements.

7.2.2.1 – In the limited information level, there are no projects of the supporting system.
Characteristics of the supporting system are determined with measurements performed.
Limited information level cannot be applied to “Buildings that Immediate Use Is required
Following an Earthquake” and “Buildings Intensely Inhabited by People for Long Periods”
defined in Table 7.7.
7.2.2.2 – In the limited information level, in case the project for the supporting system of
the building are not present, then more measurements are performed as compared to the caseof limited information. If such projects are present, then measurements defined for thelimited level are performed to confirm the information in the project.
7.2.2.3 – In the comprehensive information level, the project for the supporting system of thebuilding are present. Measurements sufficient to confirm the information in the project are
performed.
7.2.3. The Existing Material Strength
Strength of the materials to be used in the calculation of the capacities of the supporting
elements is defined as the existing materials strength.

7.2.4. Limited Information Level in Reinforced Concrete Buildings
7.2.4.1 – Geometry of the Building: The measured drawings of the supporting system shallbe prepared with field work. In case the architectural projects are present, these can be usedas aids to the works for preparation of measured drawings. Information obtained must
include the locations, axis openings, heights and dimensions of all the reinforced concreteelements and nonbearing walls, and must be sufficient for the creation of a calculation
model for the building. Foundation system shall be determined by digging examination
holes of sufficient numbers in- or outside the building. Short columns or similarirregularities in the building shall be entered on the floor plan and sections. Relation of thebuilding with the neighboring buildings (separated, adjoining, jointing present / absent)
shall be determined.
7.2.4.2 – Details of elements: Projects or application drawings are not present. It is assumed
that the amount of reinforcement in the reinforcement elements and details meet theminimum requirements for reinforcement for the date that the building was constructed.
With the purpose of confirming this assumption, or to determine to what extent it is true,
reinforcements and lengths of reinforcement laps shall be determined by scraping off theconcrete covers of 10 % of bulkheads and columns and 5 % of beams, and at least one ineach floor. Such scraping must be performed on the one-thirds of the lengths the columns

111and beams in the middle of the opening; however, same must be performed on theoverlapping parts of at least three columns with the purpose of determining the length ofoverlapping. Scraped surfaces shall be covered afterwards with high-strength repair mortar.
In addition, number of longitudinal and transverse reinforcement elements of 20 % of theelements that have not been scraped shall be determined using devices for reinforcementdetermining devices. The coefficient of actual reinforcement expressing the ratio of theamount of reinforcement the actually found in reinforced columns and beams to theminimum reinforcement shall be separately determined for columns and beams. Thiscoefficient shall be applied to all the other elements that reinforcement has not been
determined, and the possible amount of reinforcement shall thus be determined.

7.2.4.3 – Characteristics of Materials: At least two samples of concrete (borehole sample)
shall be collected from columns or bulkheads in each floor according to the conditions
stated in TS-10465, and tests shall be performed to determine the lowest pressure strength tobe considered as the existing concrete strength. Reinforcement class shall be determinedaccording to the visual examination as explained in the paragraph above, and thecharacteristic yield strength of the steel in this class shall be taken as the existing steel
strength. In this examination, elements showing corrosion in reinforcement shall be marked
on the plan, and this condition shall be taken into consideration in element capacity
calculations.
7.2.5. Medium Level Information in Reinforced Concrete Buildings
7.2.5.1 – Geometry of the Building: In case the reinforcement projects for the building arepresent, compliance of the geometry to the project shall be checked. In case there are no
projects, then measured drawings shall be prepared by field work. Information obtained
must include the locations in each floor, openings, heights and dimensions of all thereinforced concrete elements and nonbearing walls, and must be sufficient for the creationof a calculation model for the building. Information regarding the geometry of the building
must include the details required for a precise description of the mass of the building. Shortcolumns or similar irregularities in the building shall be entered on the floor plan andsections. Relation of the building with the neighboring buildings (separated, adjoining,
jointing present/absent) shall be determined. Foundation system shall be determined by
digging examination holes of sufficient numbers in- or outside the building.
7.2.5.2 – Details of elements: In case project or manufacturing drawings are not present,
then conditions in 7.2.4.2 apply; however, number of bulkheads, columns and beams that
concrete covers shall be scraped off for the checking of reinforcement shall not be less than
20 % of the total number of columns in a certain floor, and 10 % of the number of beams,
and at least two in each floor. In case project or manufacturing drawings are present, thenconditions stated in 7.2.4.2 shall be applied with the numbers stated therein. In addition,
number of longitudinal and transverse reinforcement elements of 20 % of the elements thathave not been scraped shall be determined using devices for reinforcement-determining
devices. The coefficient of actual reinforcement expressing the ratio of the amount ofreinforcement the actually found in reinforced columns and beams to the minimum
reinforcement shall be separately determined for columns and beams. This coefficient used
to determine the capacities of elements cannot exceed 1. This coefficient shall be applied to
all the other elements that reinforcement has not been determined, and the possible amountof reinforcement shall thus be determined.

112

7.2.5.3 – Characteristics of Materials: One concrete sample (borehole sample) shall becollected from columns or bulkheads in each floor not less than 3 in number, and also notless than 9 from the entire building and one sample from each 400 square meters for thetests to be performed according to the conditions stated in TS - 10465. The mean – standard
deviation values found for the samples shall be taken as the existing concrete strength whencalculating the capacities of the elements. Distribution of the concrete strength throughout thebuilding can be checked with the readings of adjusted concrete test hammer to the borehole
sample test results or similar undamaged examination tools. Reinforcement class shall be
determined by visual examination on surfaces scraped as described in the paragraph above,and the characteristic strength of the steel of this class shall be taken as the existing steel
strength in capacity calculations. In this examination, elements showing corrosion in
reinforcement shall be marked on the plan, and this condition shall be taken into
consideration in element capacity calculations.
7.2.6. Comprehensive Information Level in Reinforced Concrete Buildings
7.2.6.1 – Geometry of the Building: Reinforcement projects for the building are present.
Compliance with the projects of the actual geometry is checked with the measurements
performed in the building. In case the projects show important conflicts with themeasurements, then the projects are ignored, and the building is examined according to therules for medium level information. Short columns or similar irregularities in the building
shall be entered on the floor plan and sections. Relation of the building with theneighboring buildings (separated, adjoining, jointing present/absent) shall be determined.
Information regarding the geometry of the building must include the required details for a
precise description of the mass of the building. Foundation system shall be determined by
digging examination holes of sufficient numbers in- or outside the building.
7.2.6.2 – Details of elements: Detail projects of reinforcement of the building are present.
Procedures stated in 7.2.4.2 for checking of the compliance of reinforcement with the
project shall be applied on the same number of reinforcement elements. In addition,
locations and numbers of longitudinal and transverse reinforcement elements of 20 % of theelements that have not been scraped shall be determined using devices for reinforcementdetermining devices. In case there are any conflicts between the project and the application,then coefficient of actual reinforcement expressing the ratio of the amount of reinforcement
the actually found in reinforced columns and beams to the minimum reinforcement shall beseparately determined for columns and beams. This coefficient used to determine thecapacities of elements cannot exceed 1. This coefficient shall be applied to all the otherelements that reinforcement has not been determined, and the possible amount ofreinforcement shall thus be determined.
7.2.6.3 – Characteristics of Materials: One concrete sample (borehole sample) shall becollected from columns or bulkheads in each floor not less than 3 in number, and also notless than 9 from the entire building and one sample from each 200 square meters for thetests to be performed according to the conditions stated in TS - 10465. The mean – standard
deviation values found for the samples shall be taken as the existing concrete strength whencalculating the capacities of the elements. Distribution of the concrete strength throughout thebuilding can be checked with the readings of adjusted concrete test hammer to the borehole
sample test results or similar undamaged examination tools. Reinforcement class shall be
determined on surfaces scraped as described in the paragraph above, and tests shall be
performed on one sample for each steel class (S220, S420, e t c . ), and yield strength andbreaking strength, and deformation characteristics of the steel shall determined andcompliance with the project shall be determined. If it complies with the project, thecharacteristic strength of the steel used in the project shall be taken as the existing steel
113strength. If not, tests shall be performed on at least three more samples, and the least
favorable value shall be taken as the existing steel strength in the element capacity
calculations. In this examination, elements showing corrosion in reinforcement shall bemarked on the plan, and this condition shall be taken into consideration in element capacity
calculations.

7.2.7. Limited Information Level in Steel Constructions
Limited information level in steel constructions is not valid.

7.2.8. Medium Information Level in Steel Constructions
7.2.8.1 – Geometry of the Building: Conditions given in 7.2.5.1 are valid as they are,except that the term “reinforced” shall be replaced with “steel”.
7.2.8.2 – Details of elements: In case steel projects or manufacturing drawings are notpresent, boring controls of all the steel elements and other elements of other types (columns,
beams, joints, crosses, flooring) shall be performed, and welding characteristics and joining
details shall be established in detail. In case the application projects and manufacturing
drawings are present, then the precise dimension controls shall be performed for 20 % of thesaid elements.
7.2.8.3 – Characteristics of Materials: In case steel projects are not present, then one
sample shall be cut off from each steel construction type, and tests shall be performed todetermine the strength and deformation characteristics. Likewise, a welding sample shall be
cut off to perform tests. Such cut off places shall be filled and repaired. One sample bolt
shall be taken for tests from bolted connections. The mean strengths obtained from tests
shall be taken as existing steel strength for the calculation of the strengths of elements. In
case steel projects are present, then the characteristic strengths foreseen in the project shallbe taken as existing steel strength.
7.2.9. Comprehensive Information Level in Steel Constructions
7.2.9.1 – Geometry of the Building: Conditions given 7.2.6.1 are valid as they are, exceptthat the term “reinforced” shall be replaced with “steel”.
7.2.9.2 – Details of elements: Steel detail projects of the building are present. Dimensions of
the elements shown in the project and details of joints shall be confirmed by checking in atleast 20% of the total numbers of each element and joint types.
7.2.9.3 – Characteristics of Materials: Steel class mentioned in the project shall becontrolled by cutting a sample from at least steel element. Likewise, a sample shall be cut
off from one welded joint shown in the project and tested to control the compliance of steel
with the project. Such cut off places shall be filled and repaired. One sample bolt shall betaken for tests from bolted connections. In case compliance with the project is confirmed,
then mean strengths obtained from tests shall be taken as existing steel strength for the
calculation of the strengths of elements. Otherwise, at least three samples shall be collected
for tests, and the least favorable value shall be taken as the existing steel strength.

114

7.2.10. Limited Information Level in Prefabricated Reinforced Concrete Buildings
Limited information level in prefabricated reinforced concrete constructions is not valid.

7.2.11. Medium Information Level in Prefabricated Reinforced Concrete Buildings
Conditions mentioned in 7.2.5.1 are valid for the geometry of the building, except that theterm “reinforced” shall be replaced with “reinforced concrete”. Conditions mentioned in
7.2.8.2 are valid for the details of elements, except that the term “steel” shall be replacedwith “prefabricated reinforced”. Although conditions mentioned in 7.2.5.3 are valid for
determining the characteristics of materials, number of samples of materials shall be half as
much, provided that these samples shall not be less than three in total for each floor, and notless than 9 for the entire building.

7.2.12. Comprehensive Information Level in Prefabricated Reinforced Concrete
Buildings
Conditions mentioned in 7.2.6.1 are valid for the geometry of the building, except that theterm “reinforced” shall be replaced with “reinforced concrete”. Conditions mentioned in
7.2.9.2 are valid for the details of elements, except that the term “steel” shall be replacedwith “prefabricated reinforced”. Test shall be performed on at least one sample (borehole
sample) collected for each 500 square meters for determining concrete compression
strength. Total number of borehole samples collected from the building shall be at least 9.
Of the mean concrete compression strength obtained in tests and the value shown in the
project for concrete compression strength, one with the smaller value shall be taken as theexisting concrete strength in the calculation of the capacities of the elements. The
reinforcement strength to be used in the calculations of capacities of the elements shall be thecharacteristic strengths shown in the project for that particular steel class.

7.2.13. Limited Information Level in Masonry Buildings
7.2.13.1 – Geometry of the Building: In case the architectural projects are present,
compliance of the existing geometry with the project shall be checked with visual
examination. In case there are no architectural projects present, then the measured systemdrawings shall be prepared for the building. Information obtained must include the locationsof masonry walls in each floor, their length, thickness, spaces, and heights of floors.
Foundation system shall be determined by digging examination holes of sufficient numbers
in- or outside the building.
7.2.13.2 – Details: Types of the roof and floor, methods of joining to walls, and conditionsof girdles and headpieces shall be determined visually.
7.2.13.3 – Characteristics of Materials: Types of materials used in walls shall be visually
determined by scraping the plaster on one part of the wall. Cutting resistances of walls foreach type of wall given in Section 5 shall be taken as the basis for building strength
calculations.
7.2.14. Medium Information Level in Masonry Buildings
In addition to the procedures for limited information level, joints of walls and stability ofwalls shall be investigated.

115

7.2.15. Comprehensive Information Level in Masonry Buildings
In addition to the procedures for medium information level, at least 3 samples of wall pieces
shall be collected from the building to determine the characteristics of the materials used inwalls, and the mean values obtained from tests performed on these shall be used for the
calculations according to Section 5.

7.2.16. Information Level Coefficients(a) Information Level Coefficients to be applied to element capacities according to the levelof information obtained from the building examined are given in Table 7.1.
(b) Unless otherwise specified, material strengths shall not be divided by material
coefficients given in the relevant design regulations. The existing material strengths shall be
used in the calculations of element capacities.
TABLE 7.1 – INFORMATION LEVEL COEFFICIENTS FOR BUILDINGS
Information level
LimitedMediumComprehensive

Information level coefficient
0.75
0.90
1.00

7.3. LIMITS OF DAMAGE IN CONSTRUCTION ELEMENTS AND AREAS OF DAMAGE

7.3.1. Damage limits in cross sections
Three limit conditions have been defined for ductile elements on the cross section. These are
Minimum Damage Limit (MN), Safety Limit (GV) and Collapsing Limit (GÇ). Minimum
damage limit defines the beginning of the behavior beyond elasticity, safety limit defines thelimit of the behavior beyond elasticity that the section is capable of safely ensuring thestrength, and collapsing limit defines the limit of the behavior before collapsing. This
classification does not apply to elements damaged in a brittle condition.
7.3.2. Sectional Damaged Areas
Elements that the damages with critical sections do not reach MN are within the Minimum
Damage Region, those in-between MN and GV are within Marked Damage Region, thosein-between GV and GÇ are in Advanced Damage Region, and those going beyond GÇ arewithin Collapsing Region (Figure 7.1).
Internal Force
GV

GÇ

MN

Minimum
DamageRegionMarkedDamageRegionAdvanced
DamageRegionFigure 7.1

Collapsing Region

Deformation

1167.3.3. Definition of Damages in Cross Sections and Elements
Damage regions that cross sections belong to shall be decided according to the comparisonof the internal forces and / or deformation calculated using the methods described in 7.5 or
7.6 with the numerical values corresponding to cross section damage limits described in
7.3.1. Damage of the element shall be decided according to the cross section of the elementthat with greatest damage.
7.4. GENERAL PRINCIPLES AND RULES RELATED TO EARTHQUAKE DAMAGE

7.4.1 – According to this section of the Regulation, objective of the earthquake damage
calculation is to determine the earthquake performances of the existing or reinforcedbuildings. With this purpose, the linear elastic defined in 7.5 or the linear non-elastic
calculation methods defined in 7.6 may be used. However, the performance evaluations
conducted using these methods that are based on different theoretical perceptions should
not be expected to give exactly the same results. The general principles and rules defined
below apply for both methods.
7.4.2 – Elastic (non-reduced) acceleration spectrum given in 2.4 will be used for thedefinition of the earthquake, however, the modifications introduced on 7.8 will beconsidered for different exceeding probabilities. Building Importance Factor defined in
2.4.2 will not be applied in the seismic calculation. (I =1.0).
7.4.3 – The seismic performance of the buildings will be evaluated under the collective
impacts of the gravity loads and the seismic impacts affecting the building. Live gravity
loads will be defined in a way that they will be in conformity with the masses taken into
consideration in seismic calculation as per 7.4.7.
7.4.4 – Seismic forces will be applied to both sides of the building in both directions,individually.
7.4.5 – The ground parameters that will be used in seismic calculations will be determinedaccording to Section 6.
7.4.6 – Load-bearing system model of the building will be prepared accurately to calculate
inner force, translocation and deformations that will arise in the structural components dueto the seismic effects and the collective effects of the gravity loads.
7.4.7 – The floor weights that will be considered in seismic calculation will becalculated according to 2.7.1.2 and the floor masses will be defined in conformity withthe floor weights.
7.4.8 – For the buildings where the slabs act as rigid diaphragms on the horizontal axis,
two horizontal translocation per floor and independence levels for the rotations around thehorizontal axis will be considered. Independence levels of the floors will be defined for thecenter of mass of each floor and additional eccentricity will not be applied.
7.4.9 – The ambiguities regarding the load-bearing systems of the existing buildings will
be reflected on the calculation methods via the information level coefficients defined in 7.2
in accordance with the scope of the information gathered regarding the building.

117

7.4.10 – The columns that are defined as short column as per 3.3.8 will be defined in theload - bearing system model with their actual free lengths.
7.4.11 – The conditions regarding the definition of the interaction diagrams of thereinforced concrete sections under uniaxial or biaxial bending and axial force effects are
given below:(a) Current strengths of the concrete and reinforcement steels determined in accordancewith the information level defined in 7.2 will be taken as the basis in the analysis.
(b) Maximum pressure unit deformation of the concrete and the reinforcement steel can betaken as 0.003 and 0.01, respectively.
(c) Linearizing in a proper way, interaction diagrams can be modeled as multi-line or
multi-axis diagrams.
7.4.12 – While defining the component sizes of the reinforced concrete systems,
confinement zones can be considered as infinitely rigid end zones.
7.4.13 – Active bending rigidities (EI)e of the cracked section will be used for the reinforced
concrete components under bending effect. Unless a more accurate calculation as made, thevalue given below will be substituted for active bending rigidities:(a) For beams: (EI)e = 0.40 (EI)o(b) For columns and frames, (EI)e = 0.40 (EI)o(EI)e = 0.80 (EI)oif ND / (Ac fcm) ≥ 0.40

if ND / (Ac fcm) ≤ 0.10

Linear interpolation can be applied for the intermediate values of the axial pressure force
ND. ND will be determined via a pre-gravity load calculation in which bending rigidities of
the non-cracked sections (EI)o are used and the total masses used and corresponding loads
referred to in the seismic calculations are considered. And the calculation for the gravity
load that provides the initial conditions for the seismic calculation will be made using thebending rigidity (EI)e determined by the way given above and will be restructured inaccordance with the loads in accordance with the masses which the seismic calculations are
based on. The same rigidities will also be used in seismic calculation.

7.4.14 – Platform concrete and the reinforcements in the platform can be included in thecalculation of positive and negative plastic momentums of the beams with reinforced
concrete platforms.
7.4.15 – In the section capacity calculation in case of the reinforced concrete components
with insufficient coupling or splicing length, yield tensile of the related reinforcement canbe diminished by the amount of the shortage in the coupling and splicing length.
7.4.16 – Ground features will be reflected in the analysis model for the cases where thedeformation in the ground may affect the structural behavior.
7.4.17 – Other modeling principles defined in Section 2 are valid.

118

7.5. DETERMINING THE BUILDING PERFORMANCE IN EARTHQUAKE WITH
LINEAR ELASTIC CALCULATION METHODS
7.5.1. Calculation Methods
Linear elastic calculation methods to be used for the determination of seismic performancesof buildings are the calculations methods defined in 2.7 and 2.8. Additional rules as statedbelow shall be applied concerning these methods.
7.5.1.1 – Equivalent seismic load method shall be implied to buildings not exceed 25 m and8 storey and also have bi < 1.4 buckling disorder calculated without considering joint
eccentricity. On the calculation of total equivalent seismic load (ground shearing force)according to Equation (2.4) Ra=1 is taken and right side of the equation is multiplied with λfactor. λ Factor is taken as 1.0 in one and two storey buildings except cellar and 0.85 inothers.
7.5.1.2 – While using the Mod Combination Method, Ra=1 is taken in the Equation (2.13).
On the calculation of internal forces and capacities of elements that are adaptable to applied
seismic direction and course, internal force directions obtained in the mode that is dominant
in this direction shall be based.
7.5.2. Determination of Damage Level in the Structural Elements of Armoured
Concrete Buildings
7.5.2.1– In the description of damage boundaries of ductile elements with linear elastic
calculation methods, numerical values figured as (r) shall be used in the effect / capacity
ratios of beams, column and wall elements and sections of strengthened masonnary filledwalls.
7.5.2.2 – Armoured concrete elements are classified as “ductile” if their fracture type isbending and “brittle” if it is shearing.

a) In order the beams, columns and walls to be considered as ductile element, Ve Shearing
force calculated in accordance with the bending capacity in the critical sections of thoseelement should not exceed the shearing capacity Vr calculated according to TS - 500 byusing the values of current material strength that are comply with information level as
defined in 7.2. Calculation of Ve for columns shall be made according to 3.3.7, for beams
according to 3.4.5 and for walls according to 3.6.6 but in Equation (3.16) Ra= 1 is taken.
On the calculation of Ve for columns, beams and walls, bearing force moments shall be usedinstead of hardening bearing forces. In case the total shearing force calculated with gravity
loads by taking Ra= 1 is less than Ve, then this shearing force shall be used instead of Ve.
b) In order the beams, columns and walls to be considered as ductile element also it isnecessary to provide Hw/ w > 2.0 condition.
c) Armoured concrete elements that are not provide the conditions for ductile element
given in (a) and (b) are defined as brittle damaged elements.
7.5.2.3 – Effect / capacity ratio of ductile beam, column and wall sections is determined by
dividing the section moment calculated under seismic load by taking Ra= 1 to over moment
capacity. On the calculation of effect / capacity direction of the applied earthquake shall betaken into consideration.

119a) Over moment capacity of section is the difference between bending moment capacity ofthe section and moment effect calculated on the section under gravity loads. Moment effectcalculated under gravity loads in the supports of the beam can be reduced maximum 15 %according to retransfer principle.
b) Effect / capacity ratios of column and wall sections can be calculated in such a way as
defined in Information Annex 7A.
c) Armoured concrete columns that provide the conditions of 3.3.4 in terms of thetransverse reinforcement conditions in the coating zone, armoured concrete beams thatprovide 3.4.4 and armored concrete walls that provide 3.6.5.2 in the end zones are
considered as “coated” and those that are not provide the conditions are considered as “un coated” elements. It is necessary for the elements that are considered as “un - coated” for thecoating elements being arranged with “special seismic hoops and crossties” according to
3.2.8 and reinforcement spaces of those should be provide the conditions as defined above.
7.5.2.4 – Effect / capacity ratio of strengthened filled walls are the shearing force strength ofshearing force calculated under the effect of earthquake. Shearing forces formed in thestrengthened filled walls which are modeled with diagonal bars shall be taken into
consideration as the horizontal concurrent of the axial force of the bar. Calculation ofshearing force strength of the strengthened masonnary filled walls is given in Information
Annex 7F.
7.5.2.5 – It is decided that the elements are located in which damage zone by comparing
effect / capacity ratio of beam, column and wall sections and strengthened filled walls (r)with boundary values given in Table 7.2 - 7.5. Besides, on the determination of damage
zones of strengthened filled walls in the armoured concrete buildings boundary ratios ofrelative storey drift given in Table 7.5 shall also be taken into consideration. Ratio ofrelative storey drift shall be obtained by dividing the maximum relative storey drift to storey
height. For intermediate - values given in Table 7.2 - 7.5 linear interpolations shall beapplied.
TABLE 7.2 – EFFECT / CAPACITY RATIOS (r) DEFINES THE BOUNDARY OF
THE DAMAGE FOR ARMOURED CONCRETE BEAMS
Ductile Beams− ′Coating

b

0.0
0.0
0.5
0.5
0.0
0.0
0.5
0.5

Available
Available
Available
Available
Not available
Not available
Not available
Not available

Damage BoundaryV(1)bw d fctm≤ 0.65≥ 1.30≤ 0.65≥ 1.30≤ 0.65≥ 1.30≤ 0.65≥ 1.30

MN

GV

GÇ

3
2.5
3
2.5
2.5
2
2.5
1.5

7
5
5
4
4
3
4
2.5

10
8
7
5
6
5
6
4

(1) Ve shearing force shall be calculated according to 7.5.2.2 (a) in accordance with the direction of earthquake.

120

TABLE 7.3 – EFFECT / CAPACITY RATIOS (r) DEFINES THE BOUNDARY OF
THE DAMAGE FOR ARMOURED CONCRETE COLUMNS
Ductile Columns

Damage BoundaryN(1)
Ac f cCoatingV(2)
bw d f ctm

MN

GV

GÇ

≤ 0.1
≤ 0.1
≥ 0.4
≥ 0.4
≤ 0.1
≤ 0.1
≥ 0.4
≥ 0.4

Available
Available
Available
Available
Not available
Not available
Not available
Not available≤ 0.65≥ 1.30≤ 0.65≥ 1.30≤ 0.65≥ 1.30≤ 0.65≥ 1.30

3
2.5
2
2
2
1.5
1.5
1

6
5
4
3
3.5
2.5
2
1.5

8
6
6
5
5
3.5
3
2

(1) NK axial force shall be calculated according to Information Annex 7A.
(2) Ve shearing force shall be calculated according to 7.5.2.2 (a) in accordance with the direction of earthquake.

TABLE 7.4 – EFFECT / CAPACITY RATIOS (r) DEFINES THE BOUNDARY OF
THE DAMAGE FOR ARMOURED CONCRETE WALLS
Ductile Walls
Coating
Available
Not Available

Damage Boundary
MN
3
2

GV
6
4

GÇ
8
6

TABLE 7.5 – EFFECT / CAPACITY RATIOS (r) DEFINES THE BOUNDARY OF
THE DAMAGE FOR STRENGTHENED FILLED WALLS AND RATIOS OF
RELATIVE STOREY DRIFT

Ratio range of wall / hwall
0.5 - 2.0
Effect / Capacity Ratios (r)Ratios Of Relative Storey Drift

MN
10.0015

Damage BoundaryGV20.0035GÇ-

7.5.2.6 – In the joints of armoured column - beam, shearing force to be calculated from
Equation (3.11) and affects the joint for all boundary conditions should not exceed theshearing forces given 3.5.2.2. However, in Equation (3.11) Ve calculated without
considering hardening according to 3.3.7 shall be used instead of Vkol, whereas in thecalculation of strength in Equation (3.12) and Equation (3.13) current concrete strength
determined according to information level in 7.2 shall be used instead of fcd. In case theshearing force of joint exceeds the shearing strength, column - bema confinement zone shallbe defines as brittle damaged element.
7.5.3. Control of Relative Storey Drifts
In the calculation made with linear elastic methods in each earthquake direction, relative
storey drifts of column, beam or walls in each storey of the building shall not exceed thevalue given in Table 7.6. δji indicates the relative storey drift calculated as a replacement
difference between bottom and top ends of the j’th column or wall in i’th storey whereas
hji indicates the height of the relevant element.

121

TABLE 7.6 - BOUNDARIES OF RELATIVE STROREY DRIFT
Ratio of Relative
Storey Driftδji / hji

MN
0.01

Damage Boundary
GV
0.03

GC
0.04

7.6. DETERIMINING THE SEISMIC PERFORMANCE OF THE BUILDINGUSING INELASTIC LINEAR METHODS
7.6.1. Definition
The aim of the inelastic linear measurement methods to be used for determining thestructural performances of the buildings under seismic effect and for the strengthening
analyses is enabling the measurement of the plastic deformation volitions regarding theductile behavior and inner force volitions concerning the brittle behavior for a given
earthquake. Afterwards, the magnitudes of the mentioned volitions are compared with thedeformation and inner force capacities that are defined in this section and structural
performance evaluation shall be conducted both at sectional and building level.

7.6.2. Scope
The inelastic linear analysis methods included in the scope of this Regulation are
Incremental Equivalence Seismic Load Method, Incremental Mode Combination Method
and Measurement within the Scope of Time Definition Method. First two are the methods
that shall be used for the Incremental Repulsion Analysis that is taken as a basis fordetermining the non - linear seismic performances and for the strengthening measurements
included in this Regulation.

7.6.3. The Procedure for the Performance Evaluation via Incremental Repulsion
Analysis
The steps that shall be taken during the inelastic non - linear performance evaluation
conducted applying the Incremental Repulsion Analysis is summarized below.

(a) In addition to the general principles and rules defined in 7.4, the rules defined 7.6.4
shall be followed to idealize the non-linear behavior of the load-bearing system andconstruct the analysis model.
(b) Before applying the incremental repulsion analysis, a non-linear static analysis in which
the gravity loads that are in accordance with the masses are taken into consideration shallbe conducted. The results of this analysis shall be considered as the initial conditions of theincremental repulsion analysis.
(c) In case the incremental repulsion analysis is conducted via applying the Incremental
Equivalence Seismic Load Method defined in 7.6.5, the “modal capacity diagram”
belonging to the primary (dominant) mode the coordinates of which are defined as “modaltranslocation – modal acceleration” shall be derived. The modal translocation volition
belonging to the primary (dominant) mode shall be set taking the elastic behaviors spectrum
defined in 2.4 and the modifications applied on this spectrum in 7.8 for different exceeding
probabilities together with the mentioned diagram into consideration. In the final step, thetranslocation, plastic deformation (plastic rotation) and inner force volitions that
corresponds to the modal translocation volition shall be calculated.
122

(d) In case the incremental repulsion analysis is conducted via applying the Incremental
Mode Combination Method defined in 7.6.6, modal translocation volitions will as well bederived together with the “modal capacity diagrams” for all modes taken into considerationand the translocation, plastic deformation (plastic rotation) and inner force volitions thatwill arise accordingly in the load-bearing system shall be calculated.

e) The plastic rotation volitions that are calculated out of ductile sections shall be utilized forderiving plastic bending volitions and total bending volitions in accordance with 7.6.8. Afterwards,
the unit deformation volitions of reinforced concrete sections, concretes and reinforcementsteels shall be calculated accordingly. Performance evaluations regarding the ductile
behavior in sectional level shall be conducted via comparing the mentioned values ofvolition with the unit deformation capacities defined in 7.6.9 for various damage thresholds.
Moreover, the deformation volitions calculated in terms of relative storey drifts of thestrengthened filled wall shall be compared with the deformation capacities defined in 7.6.10.
The shear force volitions derived from the analysis on the other hand shall be comparedwith the capacities defined in 7.6.11 and performance evaluation regarding the brittle
behavior shall be conducted at sectional level.
7.6.4. Idealizing the Inelastic Non - linear Behavior
7.6.4.1 – In order to idealize the inelastic non-linear behavior in respect to the materials, the models
that are proved to be valid in the literature can be utilized. However, due to its practicability andextensiveness in engineering practices, stacked plastic behavior model is taken as a basis
point for the inelastic non-linear analysis applied in the following sections. In this modelthat corresponds to the plastic support hypothesis in case of simple bending, it is assumed
that the plastic deformations are formed in an evenly-distributed manner all along the finitelength zones in which the inner forces in the beam, column and frame-type load-bearing
components idealized as stick components reach to their plastic capacities. The length ofthe plastic deformation zone referred to as plastic support length (Lp) shall be taken as thehalf of the section length (h) in the active direction (Lp = 0.5 h). For the frames where Hw /w ≤ 2.0, the plastic deformations under the bending effect will not be taken into
consideration.
7.6.4.2 – The length of the plastic deformation zones that undergo plastic deformation only
under axial force shall be assumed to be equal to the open length of the related component.
7.6.4.3 – The plastic section that represents the stacked plastic deformation should bepositioned in the middle of the plastic deformation zone that is theoretically defined in
7.6.4.1. However, the approximate idealizations mentioned below can be allowed forpractical applications.
(a) In columns and beams, the plastic sections can be placed right out of the column-beamconfinement zone, in other words on the end zones of the net ports of columns or beams.
However, the fact that plastic hinges may be formed as well in the beam bays due to theeffects of the gravity loads should be taken into consideration.
(b) In reinforced concrete frames, plastic sections may be allowed to be placed on thebottom end zone of the frame zone for each floor. U, T, L or box-section frames should be
idealized as a single frame all arms of which works cooperatively. In case there are rigid
frames in the basement floors of the buildings, the plastic sections of this frames following
on to the upper stairs of the building should be placed starting above from the basement.

123

7.6.4.4 – The interaction diagrams that are defined in accordance with the rules defined in
7.4.11 shall be taken as the yield surfaces for the reinforced concrete sections that are
plasticized under the effect of uniaxial or biaxial bending and axial force. When they arelinearized in accordance with 7.4.11(c), the yield surfaces can be modeled as yield lines
and yield planes in case of two-dimensional and three-dimensional behaviors, respectively.
7.6.4.5 – The information in the following paragraphs shall be considered regarding theinner force – plastic deformation correlations that shall be used in repulsion analysis model.
(a) The strain hardening effect (rise in the momentum in accordance with the rise in theplastic rotation) in the inner force – plastic deformation correlations can be left
approximately (Figure 7.2a).
In such a case, the condition of the plastic deformation vector being approximately
perpendicular to the yield surface, provided that the inner forces remain over the yieldsurface, shall be taken into consideration during the steps following the plasticizing of thesections under the impact of the uniaxial or biaxial bending and axial force.

(b) In case the strain hardening effect is taken into consideration (Figure 7.2b), therequirements the inner forces and the plastic deformation vector should satisfy during therepulsion steps following the plasticization in the sections under the effect of uniaxial orbiaxial bending and axial force shall be defined in accordance with an appropriate strain
hardening model to be obtained from the related literature.
M

M

Mpa

Mpb

θp

(a)

θp

(b)

Figure 7.2
7.6.4.6 – Any filled wall that is strengthened in accordance with 7.10.4 shall be idealized as
per 7.6.4.2 as a two - edge hinged diagonal equivalent pressure and / or draw bar as definedin the Information Annex 7F. The axial rigidity and axial yield strength regarding theinitial linear elastic behavior of the equivalent stick that shall be modeled as an elastro plastic (non-hardening) component in the repulsion analysis shall be determined as per the
Information Annex 7F. The shear strength defined for the wall is the horizontal
component of the axial yield strength of the diagonal equivalent pressure stick. Whennecessary, yield strength of the diagonal equivalent draw bar shall be obtained from
Equation (7F.6).
7.6.5. Repulsion Analysis with Incremental Equivalent Seismic Load Method
7.6.5.1 – The aim of the Incremental Equivalent Seismic Load Method is implementing
the non-linear repulsion analysis under the effect of equivalent seismic loads that aregradually increased in a monotonic way up to the seismic volition threshold provided that itshall be proportional to the vibration mode type of the primary (dominant in the seismic
direction). In each step of the repulsion analysis following the gravity load analysis, thetranslocation, plastic deformation and inner force increments and cumulative values ofthese increments and finally the maximum values corresponding to the seismic volition
shall be calculated.
124

7.6.5.2 – To be able to use the Incremental Equivalent Seismic Load Method, the numberof floors of the building excluding the basement should not be above 8 and the bending
irregularity coefficient that is calculated in accordance with the elastic linear behavior
without considering additional eccentricity should meet the condition bi < 1.4 for eachfloors. Moreover, in accordance with the earthquake taken into consideration, the ratio of
the active mass of the primary (dominant) vibration mode calculated taking the linear
elastic behavior as a basis point to the total mass of the building (except for the masses ofthe basement floors covered by the rigid frames) should be above 0.70.
7.6.5.3 – During incremental repulsion analysis, the distribution of the equivalent seismic
load can be assumed to remain constant, independent of the plastic section formations in
the load-bearing system. In such a case, load distribution shall be determined in a way thatit shall be proportional to the value derived by multiplying the natural vibration modeshape magnitude of the primary (dominant in the seismic direction) that is computed for the
linear elastic behavior at the first step of the analysis with the magnitude of the related
mass. In the buildings where floor slabs are idealized as rigid diaphragms, twoperpendicular horizontal drifts in the center of mass of each floor and the rotation aroundthe vertical axis passing through the center of mass shall be considered as the magnitudesof the primary (dominant) natural vibration mode shapes.
7.6.5.4 – By means of the repulsion analysis conducted in accordance with the constantload distribution defined in 7.6.5.3, the repulsion curve the coordinates of which are “toptranslocation – ground shear force” shall be obtained. Top translocation is thetranslocation that is calculated in each repulsion step and that takes place in the center ofmass of the top floor of the building for the earthquakes in the direction x that are taken
into consideration. And the ground shear force is the sum of the equivalent seismic loads ofeach step for the earthquake in the direction of x. With the help of the coordinatetransformation applied to the repulsion curve, the modal capacity diagram the coordinatesof which are “modal translocation – modal acceleration” can be obtained via the method
defined below:(a) The modal acceleration for the primary (dominant in the seismic direction) mode forthe (i)’ th step, a1(i), is derived with the following method:a1(i) =

Vx1(i)
M x1(7.1)(b) The following equation can be used to calculate the modal translocation for the
primary (dominant in the seismic direction) mode for the (i)’ th step, d 1(i):(i)uxN1d1(i) =
(7.2)
Φ xN1 Γ x1
The contribution coefficient for the primary (dominant in the seismic direction) mode, Γ x1 ,is computed in the following way, utilizing the values Lx1 and M1 that are defined for the
linear elastic behavior of the load-bearing system for the earthquake in the direction x andis given in Chapter Equation (2.15):

Γ x1 =

Lx1
M1

(7.3)

125

7.6.5.5 – As an alternative to 7.6.5.3, during the incremental repulsion analysis,
equivalent seismic load distribution can be considered as varying in each repulsion step
compared to the previous steps. In such a case, the load distribution shall be defined as
proportional to the value obtained from multiplying the magnitudes of the primary(dominant) natural vibration mode shapes that are calculated considering all plastic sections
formed in the load-bearing system before each repulsion step with the magnitude of therelated mass. In the buildings where floor slabs are idealized as rigid diaphragms, themagnitudes of the primary (dominant) natural vibration mode shapes shall be defined asgiven in 7.6.5.3.
7.6.5.6 – The maximum modal translocation of the primary (dominant) mode, i.e. modaltranslocation volition shall be set taking the elastic behaviors spectrum defined in 2.4 andthe modifications applied on this spectrum in 7.8 for different exceeding probabilities
together with the modal capacity diagram derived as a result of the repulsion analysis as per
the information given in 7.6.5.4. As a definition, modal translocation volition d1(p) is
equivalent with the non - linear spectral translocation Sdi1.
(7.4)
d1(p) = Sdi1
The calculations regarding the determination of non-linear spectral translocation Sdi1 isgiven in Information Annex 7C.
7.6.5.7 – By substituting the modal translocation volition d1 (p) that is determined according
to Equation (7.4) for the final repulsion step i = p in Equation (7.2)’, the top the top(p)translocation volition uxN1
for the x seismic direction, shall be obtained.
(p)uxN1= Φ xN1 Γ x1 d1(p)(7.5)
All other volition magnitudes (translocation, deformation and inner force volitions)corresponding to this value shall be obtained from the existing repulsion analysis file orshall be computed with a new repulsion analysis that shall be conducted until the top
translocation volition is reached.

7.6.6. Repulsion Analysis with Incremental Mode Combination Method
The aim of the Incremental Mode Combination Method is incrementally implementing theMode Combination Method taking modal translocations that are gradually andmonotonically increased in a way that shall be proportional to the sufficient number ofnatural vibration mode shapes representing the load-bearing system behavior and that are
scaled in a way that they shall be in harmony with each other or taking the modal seismic
loads that shall be in harmony with the mentioned modal. Such repulsion analysis methodthat is based on the “step by step linear elastic” behavior in the load - bearing system foreach repulsion step between the formations of two sequential plastic sections is explainedin Information Annex 7D.

7.6.7. Calculation with the Non-linear within the Scope of Time Definition Method
7.6.7.1 – The aim of the Calculation with the Non - linear within the Scope of TimeDefinition Method is integrating the movement equation of the system step by step taking
the non-linear behavior of the load-bearing system. During the analysis, translocation,
plastic deformation and inner force that come up in the system in each increment and the
maximum values of these magnitudes that correspond to the seismic volition are calculated.

1267.6.7.2 – The artificial, recorded or simulated earth movements that shall be used in the analysis
to be conducted in the time definition scope shall be determined as per 2.9.1 and 2.9.2 and2.9.3 shall be taken into consideration through the analysis.
7.6.8. Determining the Unit Deformation Volitions
7.6.8.1 – The plastic bending volition dependent on the p plastic rotation volition that shall beobtained in any section as a result of the repulsion analysis conducted as per 7.6.5 or 7.6.6 orobtained as a output information onto the calculation conducted within the scope of time
definition as per 7.6.7 shall be calculated as follows:
θp
φp =
(7.6)
Lp
7.6.8.2 – The total bending volition φt of the section shall be obtained adding the φyequivalent yield bending that is defined with the two-line momentum-bending relationshipobtained from the analysis conducted under the axial force volition of the section by meansof using a reinforcement steel model that as well considers the strain hardening together
with a concrete model chosen in accordance with the aim to the φp plastic bending
volition defined with the Equation (7.6):(7.7)
φt = φ y + φp
The unit pressure deformation volition in the reinforced concrete systems and the unit
deformation volition in the reinforcement steel shall be calculated applying momentumbending analysis in accordance with the total bending volition defined with Equation (7.7).

7.6.8.3 – If any other choice is not introduced, Information Annex 7B can be utilized forcoated or uncoated concrete and reinforcement steel models.
7.6.9. Section Unit Deformation Capacities of Reinforced Concrete Components
7.6.9.1 – The seismic volitions obtained in accordance with 7.6.8 in terms of unit
deformation volitions for concrete or reinforcement steel shall be compared with the unit
deformation capacities given below so as to determine the performance of the load-bearing
systems at sectional level.
7.6.9.2 – The upper bounds (capacity) of deformation for different sectional damage
thresholds for the ductile load-bearing system components that undergo plastic
deformations are defined below:
The transverse reinforcements that consider the following:(a) For M i n i m u m S e c t i o n a l D a m a g e B o u n d a r y (MN), upper bounds of the concrete
unit pressure deformation in the outmost fiber of the section and the reinforcement steel unit
deformation volitions:( cu) MN= 0.0035;( s) MN = 0.010(7.8)(b) For Section Security Bound (GV), upper bounds of the concrete unit pressure
deformation in the outmost fiber of hoop and the reinforcement steel unit deformation
volitions:( cg) GV = 0.0035 + 0.01 ( s / sm)≤ 0.0135;( s) GV = 0.040

(7.9)

127

(c) For Section Collapse Bound (GÇ), upper bounds of the concrete unit pressure deformationin the outmost fiber of hoop and the reinforcement steel unit deformation volitions:( cg )GC = 0.004 + 0.013 ( s / sm ) ≤ 0.018 ; ( s )GC = 0.060(7.10)
Should be regulated as “special earthquake hoops and crossties” as per 3.2.8.

7.6.10. Deformation Capacities of the Strengthened Filled Walls
The allowed boundary values (capacities) for the relative floor drifts that are obtained onto therepulsion analysis conducted via modeling the filled walls that are strengthened in accordancewith 7.10.4 and Information Annex 7F together with the columns and beams surrounding thewalls in accordance with 7.6.4.6 are listed in the second row of Table 7.5.

7.6.11. Shear Force Capacities of the Reinforced Concrete Load-Bearing System
Components
7.6.11.1 – The shear strengths that shall be used in brittle bending controls of all reinforced
concrete load-bearing components except for the confinements of columns and beams shall be
determined in accordance with the TS-500 standard. The current strength values that are
defined in accordance with the information levels set in 7.2 shall be utilized in shear force
calculations. The components the shear force strengths of which are smaller than their shear
force volition shall be defined as brittle damaged components.
7.6.11.2 – The shear force volitions that shall be calculated using Equation (3.11) for
reinforced concrete column-beam confinements should not exceed the shear strength
given in 3.5.2.2. However, in Equation (3.11) the shear force volition calculated in the nonlinear analysis for the related column shall be used instead of Vkol, and the current concrete
strength that shall be determined in accordance with the information level defined in 7.2 shallbe taken as a basis point in the strength calculation in Equation (3.12) or Equation (3.13)
instead of fcd. In case the shear force volition exceeds the shear strength, column-beamconfinement section shall be defined as brittle damaged component.
7.7. DETERMINING THE SE SM C PERFORMANCE OF THE BUILDING
7.7.1. Seismic Performance of Reinforced Concrete Buildings
The seismic performance of the buildings are related to the condition of the damages that are
expected to come out under the effect of the earthquakes applied and is defined taking four
different damage levels as basis. The seismic performance of the buildings are determined
applying the calculation methods defined in 7.5 and 7.6 and deciding on the damage areas of
the components. The rules to be applied so as to determine the seismic performance of thebuildings are given below. The rules given here are related to the reinforced concrete andprefabricated buildings. The rules to be applied for masonnary buildings are given in 7.7.6.

7.7.2. Ready for Use Performance Level
Onto the results of the calculations regarding all earthquakes applied in any floors, at most 10% of the beams exceed the Significant Damage Zone and all other load-bearing components
remain in the Minimum Damage Zone. Such buildings can be agreed to be in the Ready for
Use Performance Level provided that the brittle damaged components, if any, arestrengthened.

128

7.7.3. Life Safety Performance Level
The buildings that satisfy the conditions mentioned below can be agreed to be in Life Safety
Performance Level provided that the brittle damaged components, if any, are strengthened:(a) As the result of the calculations made for each earthquake direction applies on eachfloor, at most 30 % of the beams except for the secondary ones (that does not take place inthe horizontal load-bearing system) and at most the proportion of the columns defined inparagraph (b) can exceed the Advanced Damage Zone.
(b) The total contribution of the columns in the Advanced Damage Zone to the shear
force that is borne by the columns in each floor should not exceed 20 %. For the top
floor, the ratio of the total shear forces of the columns in the Significant Damage Zone
to the total shear forces of all the columns at that floor can be at most 40 %.
(c) All other load - bearing components are in Minimum Damage Zone or Significant
Damage Zone. However, the shear forces borne by the columns which exceeds the Minimum
Damage Bound both in upper and lower sections for any floor should not be more than 30 %of the shear force borne by all columns of the floor (In calculation with linear elastic method,
the columns that satisfy Equation (3.3) both in upper and lower confinement points are notincluded in this calculation).
7.7.4. Pre - Collapse Performance Level
The buildings that meet the conditions given below are agreed to be in the Pre - Collapse
Performance Level provided that the fact that all components that are brittle damaged are in
the Collapse Zone.

(a) Onto the results of the calculations regarding all earthquakes applied in any floors, at
most 20 % of the beams except for the secondary ones (that does not take place in thehorizontal load-bearing system) can enter the Collapse Zone.
(b) All other load-bearing components are in Minimum Damage Zone, Significant
Damage Zone or in the Advanced Damage Zone. However, the shear forces borne by thecolumns which exceeds the Minimum Damage Bound both in upper and lower sections forany floor should not be more than 30 % of the shear force borne by all columns of the floor(In calculation with linear elastic method, the columns that satisfy Equation (3.3) both inupper and lower confinement points are not included in this calculation).
(c) Usage of the building under these circumstances poses threats towards life safety.
7.7.5. Collapse Level
If the building does not satisfy the Pre - Collapse Performance Level, it is in the Collapse
Level. Usage of the building under these circumstances poses threats towards life safety.
7.7.6. Determining the Seismic Performance of Masonnary Buildings
The performance level of the masonnary buildings shall be determined onto the evaluations
made in accordance with 7.2 and the calculations made in accordance with Section 5. If theshear strength of all walls of the masonnary building in both two directions is enough to bear
the shear forces that form under the effects of the earthquakes applied, the building is decided
to satisfy Ready for Usage Performance Level. If the contribution of the walls that do notsatisfy this condition due to the earthquakes applied in any floor to the floor shear force isbelow 20 %, the building shall be decided to satisfy the Life Safety Performance Level. Only
the walls with low performance should be strengthened at least up to the level defined in
7F.2. Except for these situations the buildings are assumed to be in the Collapse Level.

1297.8. TARGETED PERFORMANCE LEVELS FOR THE BUILDINGS
7.8.1. The acceleration spectrum defined for to-be-built buildings in 2.4 takes theearthquakes for which the possibility to be exceeded in 50 years is 10 % according to 1.2.2.
In addition to this earthquake level, two different seismic given below are defined to evaluate
the existing buildings and to be utilized in strengthening designs:(a) The coordinates of the acceleration spectrum of the earthquakes for which the possibility
to be exceeded in 50 years is 50 % shall be taken as approximately the half of the coordinatesof the spectrum defined in 2.4.
(b) The coordinates of the acceleration spectrum of the earthquakes for which the possibility
to be exceeded in 50 years is 2 % is decided to be taken as approximately 1.5 times of thecoordinates of the spectrum defined in 2.4.
7.8.2. The earthquakes levels that the seismic performances of existing or to-be-strengthened
buildings shall be based on and the minimum performance targets for the buildings at thementioned earthquakes levels are given in Table 7.7.
TABLE 7.7 – MINIMUM BUILDING PERFORMANCE TARGETS
ANTICIPATED FOR DIFFERENT EARTHQUAKE LEVELSThe usage purpose and theType of the Building

Probability for the Earthquake
to be exceeded
50 % in
10 % in
2 % in50 years
50 years 50 years

The buildings that should be used after earthquakes:
Hospitals, heath facilities, fire stations, communications and–energy facilities, transportation stations, provincial or
district administrative bodies, disaster management centersetc.
The buildings that people stay in for a long time period:
Schools, accommodations, dormitories, pensions, military–
posts, prisons, museums, etc.
The buildings that people visit densely and stay in for a RU
short time period: cinema, theatre and concert halls, culture
centers, sports facilities
Buildings containing hazardous materials: The buildings–
containing toxic, flammable and explosive materials and thebuildings in which the mentioned materials are stored.
Other buildings: The buildings that does not fit the–definitions given above (houses, offices, hotel, tourist
facilities, industrial buildings, etc.)
RU: Ready for Usage; LS: Life Safety; PC: Pre-Collapse (See 7.7)

RU

LS

RU

LS

LS

–

RU

PC

LS

–

7.9. STRENGTHENING THE BUILDINGS
Strengthening the buildings covers applications such as eliminating the defects that will leadto seismic damages, adding new components that will contribute to the enhancement ofearthquake safety, diminishing the mass, improving the seismic behavior of existing
components and maintaining the continuity of force distribution.

1307.9.1. Determining the Seismic Safety of the Buildings Strengthened
The calculation methods and evaluation basis given in this section shall be used indetermining the seismic performance of the buildings and components strengthened.

7.9.2. The Design of the Components to be added to the Buildings
The special rules given in this section together with the rules in Section 3 and / or Section 4
and other standards and regulations in effect shall be followed regarding the design of thecomponents to be added to the buildings with strengthening purposes.

7.9.3. Strengthening Types
Strengthening applications shall be evaluated under two different scopes, at component leveland building system level, for each load-bearing system type.

7.9.3.1 – The applications applied to improve the strength and deformation capacities of theseismic load-bearing building components as beam, column, frame and confinement zones
are defined as component strengthening.
7.9.3.2 – The applications introduced with the aims of improving the strength anddeformation capacity of the load-bearing system of the building and ensuring the continuityof the inner force distribution, adding new components to the building, strengthening theconfinement zones and diminishing the mass of the building to minimize the seismic effects
are called system strengthening.
7.10. STRENGTHENING REINFORCED CONCRETE BUILDINGSThe component and system strengthening methods given in this section covers techniques
frequently used in practice. However, the strengthening methods that are not included in thissection can as well be applied provided that the general perception and principles of thesection are followed.

7.10.1. Coating the Columns
Following methods can be used to improve shear and pressure strength of the columns toenhance the ductility of the columns and to eliminate the weaknesses of the lap splicing. The
bending capacity of the columns can’t be improved using these methods.

7.10.1.1 – Reinforced Concrete Coating: It shall be applied via pealing off the rusted area or
rumpling the surface of the existing column. Reinforced concrete coating should have thethickness that is enough to be able to install horizontal and vertical reinforcements, pourconcrete and sustain the minimum rust area. Minimum coating thickness is 100 mm.
Concrete coating should begin from the top of the base floor slab and ends at the bottom of
the top floor slab. For the coating activity that shall be held with the aim of improving theaxial pressure strength, the rules defined in 3.3.4.2 shall be followed throughout the totalheight of the column for the transverse reinforcement in the coating concrete. Coated grosssectional dimensions and the design strength of the coating concrete shall be used in
calculating the shear and pressure strength of the coated column, but the strengths derived
shall be diminished via multiplying the values with 0.9.

131

7.10.1.2 – Steel Coating: Steel coating is constituted by installing four longitudinal angle
bracelets to the edges of rectangular reinforced concrete columns and welding the angle
bracelets to the horizontal plates positioned within specific spacing. There shouldn’t be any
gap between the angle bracelets and reinforced concrete surfaces. Horizontal plates should becontinuous in all four surfaces. For the steel coating to improve the axial load capacity of thecolumn, the angles should be continuous (the gaps should be eliminated) between the floor
and ceiling slabs and the fact that pressure transfer is enabled via the cap plates should beshown in the calculations. If required, pre-loading can be applied to the angle bracelets andthe axial pressure load on the existing concrete column section resulting from the gravity
load can be diminished. The additional shear strength introduced with the steel coating shallbe calculated using Equation (7.11).
t bd(7.11)
Vj = jf yw
s
In Equation (7.11), tj, b, and s represents the thickness, width and the spacing of thehorizontal plates and d represents the useful height of the section. To eliminate theweaknesses of lap splicing using steel coating, the length of the coating should be at least 50% higher than that of the splicing zone and the steel coating should be tightened with at least
16 mm-diameter bolted anchor that shall be fitted to the reciprocal surfaces of the column inthe reinforcement splicing zone. In case the splicing adjunction is applied in the floor edge ofthe column, at least two rows of bolted anchoring shall be applied in 250 and 500 mm above
the slab floor, respectively.
7.10.1.3 – Coating with fiber polymer (FP): Coating is enabled via coating and fixating the
FP layer around the column provided that the fibers are parallel to the transverse
reinforcements. By means of FP coating, ductility capacity, shear and pressure strengths of
the reinforced concrete columns and reinforcement coupling strength, when the splicing
length of the longitudinal reinforcement is insufficient, are improved. For the FP method, fullcoating (coating the whole section circle) method should be applied and at least 200 mm
splicing should be made after coating. FP shall be applied for the rectangular columns via
rolling the edges of the beams at least with 30 mm diameter. FP application should be heldin accordance with the method recommended by the producer firm. The calculation methods
regarding the improvement in the shear, axial pressure and coupling strengths and ductility of
the columns coated with FP a r e g i ve n i n Information Appendix 7E.
7.10.2. Improving the Bending Capacity of the Columns
Columns sections can be expanded to improve the bending capacity of the columns. Thisapplication as well improves the shear and pressure strengths of the columns. The continuityof the longitudinal reinforcements attached to the column expanded should be ensured.
Longitudinal reinforcements will pass through the holes bore on floor slabs and shall be fitted
bending into the slot bore in the upper surface of the slab. The necessary horizontal
reinforcement shall be fitted via boring holes in beams in the column-beam splicing zones orapplying anchoring to the beams. The expanded section of the column shall be coated withtransverse reinforcement in accordance with 3.3.4. The rusting area of the expanded column
shall be thick enough to cover the horizontal and vertical reinforcement fitted. In other words,
the plaster layer on the surface of the existing column shall be pealed of and concrete surfaces
shall be roughened up to ensure the adherence of the old and the new concrete. Coated grosssectional dimensions and the design characteristics of the coating concrete shall be used in
calculating the shear and pressure strength of the coated column, but the strengths derived shallbe diminished via multiplying the values with 0.9.

132

7.10.3. Coating the Beams
The purpose of coating the reinforced concrete beams is improving the shear strengths and insome cases the ductility capacities of the beams. Bending capacities of the beams can’t be
improved using the methods given below.

7.10.3.1 – Adding External Hoop: In the beam support sections where the shear strength isinsufficient, required number of hoops shall be added externally to the both surfaces of thebeam, as shown in Figure 7.3. The sticks attached to a steel profile, positioned under thebeam, with bolts shall be passed through the holes bore on upper slabs and shall be fitted
bending into the slot bore in the upper surface of the slab. Afterwards, the holes formed on
the concrete shall be filled with concrete. This method can as well be applied implementing
different details under the same principles. The shear force of the beams improved by theaddition of external hoops shall be calculated as per TS-500 standard. Externally added
hoops doesn’t have coating effect, they don’t improve beam ductility. During the application,
profiles and bolts should be protected from the outside effects.
7.10.3.2 – Coating with fiber polymer (FP): Full coating (coating the whole section circle)
method should be used for improving the beam ductility and shear force with FP coating.
The beam shear force strengthened with FP can be calculated using Equation (7E.1) given inInformation Annex 7E. In case non - continuous FP (in form of strings), the spacing
between the strings shouldn’t exceed the value (wf + d 4). FP shall be applied via rolling theedges of the beams at least with 30 mm diameter. For the FP coating, at least 200 mm
splicing should be made after coating. FP application should be held in accordance with themethod recommended by the produced firm.
Repair Concrete

Outer Hoop
Steel profile

7.10.4. Strengthening the Filled Walls
Provided that the method is applied at most for three floors except for the basement, therigidity and shear strength of the filled wall in the reinforced concrete frame constantly
continuous from the top of the grounding up to the top may be improved using thestrengthening methods defined in Information Annex 7F.

7.10.5. Improving the Reinforced Concrete Load-bearing Systems on-site castReinforced Concrete Frames
The reinforced concrete load-bearing systems with insufficient lateral rigidity can bestrengthened using on-site cast reinforced concrete frames. Reinforced concrete frames canbe fixed within the existing frame plane or as a confinement to the frame plane.
1337.10.5.1 – Installing Reinforced Concrete Walls within the Frame Plane: The frames to be
added to the reinforced concrete system shall be designed in the frame axis and shall be
continuous from the grounding to the top elevation of the frame. With this purpose, thetransverse reinforcements on the end zone of the wall and the longitudinal reinforcements inthe wall body when required shall be ensured to be continuous. The walls shall beconnected to the frame they are on with anchor sticks and they shall be ensured to work
together with the frame. Anchor sticks will have the strength enough to meet the slip tensilethat will come out between the existing frame components and the added reinforced
concrete wall components due to the seismic load. The distribution of the slip tensile in theinterfaces along the frame components shall be calculated in accordance with the common
principles of mechanics. Friction shear principles stated in TS - 500 shall be the basis point
in designing the anchor sticks. Minimum anchor stick diameter should be 16 mm, minimum
anchor depth should be one times of the stick diameter and the widest spacing between
sticks should be 40 cm. In case there aren’t any existing columns in the end zone of thewall, wall end zone shall be constructed as per 3.6.5. If there isn’t any column in the endzone of the wall, the existing column can be utilized as an end zone. When necessary, end
zone of the wall shall be constructed via expanding the existing column in accordance with
7.10.2 or constructing a hidden column inside the wall adjacent to the existing column. In
both cases, the vertical reinforcements to be added to the end zones of the wall should beensured to be continuous between the floors. Grounding shall be laid under the wall inaccordance with the rules given in 6.3.1. Wall grounding shall be sized in a way that will
enable the inner forces created in wall floor to be securely transferred to the grounding
floor.
So as to diminish the eccentricity possible to be formed in the wall grounding, axialpressure loads of the existing columns can be utilized via expanding the wall grounding in a
way that it will cover neighboring columns. Precautions required to enable the wall
grounding to work together with the existing grounding system should be taken.

7.10.5.2 – Attaching Reinforced Concrete Wall Adjacent to the Frame Plane: The walls tobe added to the reinforced concrete system shall be designed to be adjacent to the frame
outside the outer frame axis and shall be continuous beginning from the grounding up to the
top elevation of the wall. The walls shall be connected to the frame they are adjacent to withanchor sticks to ensure that they work together with the frame. Anchor sticks will have thestrength enough to meet the slip tensile that will come out in the interfaces between theexisting frame components and the added eccentric wall components due to the seismicload. The rules stated in 7.10.5.1 shall be followed in the design of anchor sticks.
In case there aren’t any existing columns in the end zone of the wall, wall end zone shall be
constructed as per 3.6.5. If there isn’t any column in the end zone of the wall, the existingcolumn can be utilized as an end zone. When necessary, end zone of the wall shall be
constructed via expanding the existing column in accordance with 7.10.2. Grounding shallbe laid under the wall in accordance with the rules given in 6.3.1. Wall grounding shall be
sized in a way that will enable the inner forces created in wall floor to be securelytransferred to the grounding floor. So as to diminish the eccentricity possible to be formedin the wall grounding, axial pressure loads of the existing columns can be utilized via
expanding the wall grounding in a way that it will cover neighboring columns. Precautions
required to enable the wall grounding to work together with the existing grounding systemshould be taken.

1347.10.6. Adding New Frames to the Reinforced Concrete System
The horizontal loads can be distributed via adding new frames to the exterior of thereinforced concrete system. The grounding of the frames to be added to the system shall beorganized together with the grounding of the existing building. To sustain that the newframes will work together with the load-bearing system of the existing building, the frames
shall be attached to the slabs in a way that will enable load transfer.

7.10.7. Diminishing the Mass of the Reinforced Concrete System
Mass reduction is not a structure strengthening method. However, as the gravity loads andseismic forces that affect the building will diminish proportional to the reducing mass the
structural safety shall be improved. The closer the mass to be reduced or removed to the top
elevations of the building, the more effectiveness on increasing the seismic security shall be.
The most effective mass reduction methods are reversing and removing the top floor or
floors of the building, replacing the existing roof with a lighter one, taking installation
weights on the roof such as water tanks to the ground and replacing heavy balconies,
parapets, partition walls and slabs with lighter components.

135

INFORMATION ANNEX 7A
DETERMINATION OF EFFECT / CAPACITY RATIOS OF COLUMNS ANDWALLS DO RUSAL IN DESIGN WITH LINEAR ELASTICITY METHODS
7A.0. NOTATION

MA
MD
ME
MK

=
=
=
=

NA
ND
NE
NK
r
rs

=
=
=
=
=
=

Residual moment capacity
Moment composed from vertical powers
Moment consisted under the earthquake power
Moment capacity calculated in accordance with existing material strength
according to 7.2.
Axial power correspond to momentary moment capacity
Axial power consisted from vertical powers
Axial power consisted under the earthquake power
Axial power correspond to cross section moment capacity
Ratio of exposure / capacity
The limit value of ratio of exposure / capacity

7A.1. Effect / Capacity Ratios in Columns and Walls
On the calculation made with linear elasticity methods, methods to be implemented for
determining the effect / capacity ratios in the sections of columns and walls under the effectof moment - axial force are specified in following paragraphs.

7A.1.1 – Moment - axial force interaction diagram of any column or wall section thatlinearized according to 7.4.11(c) is seen in Figure 7A.1. Coordinates of point D in Figure
corresponds to MD – ND couple formed of gravity loads. Vertical and horizontal projectionsof second line segment which starts from D point and step out of interaction diagram
corresponds to ME – NE couple obtained from seismic design for Ra = 1 and comply withthe direction of earthquake(In Figure 7A.1 two condition where ME indicators are different
is shown separately). Coordinates of second line segment where intersects point K is MK
moment capacity of column or wall section or the NK axial force that corresponds to it.
7A.1.2 – According to 7.5.2.3, redundant moment capacity MA and corresponding axial
force NA defined as follows:
MA = MK – MD

(7A.1a)NA = N K – N D(7A.1b)And effect / capacity ratios of columns and walls may be defined as follows:
M E NE=≤ rs(7A.2)M A NAIn case MK or NK as the coordinates of K intersection point in Figure 7A.1 is obtained
geometrically or numerically, then by using Equation (7A.1) and Equation (7A.2) the
effect / capacity ratio of the section under bending and axial force can be directly
determined as far as MD or ND is known from gravity load design and ME or NE is known
from seismic design. The axial force NK which correspond to moment capacity of the column
section is the axial force to be considered in Table 7.3 that defines boundary of damage.
r=

136

N

(MK; NK )(MD; ND )

NE
K
NA

D
M
MA
ME

N

Figure 7A.1
7A.1.3 – Effect / capacity ratio of column or wall may also be determined with a successive
approach method. For that purpose, estimation is made for r in the beginning. As NE isknown from seismic calculation NA is calculated from Equation (7A.2) and also as ND isknown NK is found from Equation (7A.1b). Accordingly, MK moment capacity is obtained
from section calculation and by subtracting MD from this value MA is calculated from
Equation (7A.1a). By using MA and ME new value of r is determined from Equation(7A.2) and by turning back to beginning pass through the forward step of the successive
approach. Value of r in the last step of successive approach which is obtained nearlysufficient to the previous step is defines as the effect / capacity ratio of the section under
bending and axial force. MA and NA values in the last step are put their places in Equation(7A.1) and MK and NK are calculated. The obtained NK is the axial force to be considered inTable 7.3 that defines the damage boundaries.
7A.1.4 – Effect / capacity ratio specified above for the unidirectional bending / axial force
is also implied similarly for bidirectional bending / axial force.
7A.2. Special Conditions
7A.1 can not be implied in case the end of second line in Figure 7A.1 remains in theinteraction diagram. It is obvious that the calculation of the ratio of effect / capacity is not
required in this situation as against to r < 1.

137

7A.3. Upper boundary of axial forces of column and wall
In the relevant column and columns on it, upper boundary of the NK axial force which is
calculated in a way as specified above in the pressure or tensile conditions can be definedas the axial force obtained as a result of the transfer of Ve shear forces calculated inaccordance with the direction of earthquake implied according to 3.4.5.1 without
considering hardening.

138

INFORMATION ANNEX 7B
TENSILE - DEFORMATION CORELATIONS FOR CONCRETE AND STEELREINFORCEMENT
7B.0. NOTATION

As
ai
bo

=
=
=

Ec
Es
fc
fcc
fco
fe
fs
fsy
fsu
fyw
ho

=
=
=
=
=
=
=
=
=
=
=

ke
s
ρs

=
=
=

ρx, ρy

s

=
=
=
=
=

su

=

c
cu
sy

Longitudinal reinforcement area
Distance between vertical reinforcement axis in the cross section bordering
Size of the cross section between the axis of lateral reinforcement binders
which covers the hub concrete
Elasticity module of concrete
Elasticity module of reinforcement steel
Concrete pressure stress in coated concrete.
Coated concrete strength
Concrete pressure stress in non-coated concrete.
Effective winding pressure
Tension in reinforcement steel
Yield strength of the reinforcement steel
Breaking strength of the reinforcement steel
Yield strength of the transversely reinforcement
Size of the cross section between the axis of lateral reinforcement binders
which covers the hub concrete
Enswathed Effectiveness Coefficient
Lateral reinforcement binders space
Volumetric ratio of total transversely reinforcement (in rectangular crosssections ρs= ρx+ρy
Volumetric ratio of transversely reinforcement in direction represents.
Deformation of pressure concrete unit
Deformation of maximum pressure unit in coated concrete
Yield unit deformation of reinforcement steel
Yield unit deformation of reinforcement steel in the beginning of strain
hardening
Breaking unit deformation of reinforcement steel

7B.1. Coated and Uncoated Concrete Models
On the performance evaluation with Linear Inelastic Methods according to 7.6, in order to
use in cases where any other model is not chosen, the following tensile - deformation
corelations are defined for coated and uncoated concrete (Figure 7B.1)*.

(a) Concrete compressive stress in coated concrete fc, is given with the following
corelation as the function of compressive unit deformation c:
fc =f cc x r

r − 1 + xr

(7B.1)

Relation between coated concrete strength fcc and uncoated concrete strength fco in thiscorrelation is given below.
ff(7B.2)
f cc = λ c f co;
λ c = 2.254 1+7.94 e − 2 e − 1.254
f co
f co

*

Mander, J.B.,Priestley, M.J.N., Park, R. (1988). Theoretical Stress - Strain Model for Confined Concrete,
Journal of Structural Division (ASCE), 114 (8), 1804 -1826139

fe effective coating pressure in here, can be taken as the average of values given below for
the two perpendicular directions in rectangular sections:;f ex = ke ρx f yw
f ey = ke ρ y f yw (7B.3)
In these correlations fyw yield stress of the transverse reinforcement indicates thevolumetric ratios of transverse reinforcements in x and y relevant directions whereas ke
indicates coating performance factor as defined below.
ai2
ke = 1 −6bo ho

s
1−
2bo

s
1−
2ho

A
1− s
bo ho

−1

(7B.4)

Here ai indicates the distance between the axes of vertical reinforcements in the peripheryof section, bo and ho indicates the section sizes remain among the axes of hoops that coats
the core concrete, s indicates the distance between the axes of hoops in vertical direction,
As indicates area of longitudinal reinforcement. Correlations concerning x and r variable ofnormalized concrete unit deformation in Equation (7B.1) are given below.
x=
r=

εc
εcc

Ec
Ec − Esec

εcc = εco [1 + 5(λ c − 1)];Ec ≅ 5000 f co [MPa ];εco ≅ 0.002;;

Esec =(7B.5)

f cc
εcc(7B.6)

Maximum compressive unit deformation in coated concrete cu is given below:
εcu = 0.004 +1.4 ρs f yw εsu(7B.7)

f cc

Here s indicates the total volumetric area of transverse reinforcement (in rectangularsections s = x + y), su indicates the unit deformation due to strain under maximum
tensile in transverse reinforcement steel.

(b) Equation (7B.1) as given for coated concrete is also available for uncoated concrete in
the zone up to c = 0.004. fcc = fco ve cc = co is taken in Equation (7B.5) and Equation(7B.6) as the effective coating pressure fe = 0 in uncoated concrete and accordingly c=1
from the Equation (7B.2). fc = 0 is defined in c = 0.005. In 0.004 < c 0.005 range,
tensile - deformation relation is linear.
fc
Coatedfcc

fco

Uncoated

co=0.002

0.004 0.005

cc

cu

c

Figure 7B.1
140

7B.2. Reinforcement Steel Model
In order to use in the performance evaluation with Linear Inelastic Methods according to
7.6, the following tensile - deformation corelations are defined for reinforcement steel.
(Figure 7B.2):
fs = Es εs(εs ≤ εsy )fs = fsy(εsy < εs ≤ εsh )fs = fsu − (fsu − fsy )(εsu − εs ) 2(7B.8)(εsh < εs ≤ εsu )(εsu − εsh ) 2

Elasticity modulus of reinforcement steel is Es = 2*105 MPa. Information concerning
reinforcement steel with quality S220 and S420 can be taken from the following table.
QualityS220
S420

fsy (Mpa)
sy
220
0.0011420
0.0021

sh

0.011
0.008

su

0.16
0.10

fsu (Mpa)
275
550

fs
fsu
fsy

sy

sh

su

s

Figure 7B.2

141

INFORMATION ANNEX 7C
DETERMINATION OF NON - LINEAR SPECTRAL REPLACEMENT
7C.0. NOTATION

a1
ay1
CR1
d1
dy1
d(p)1

=
=
=
=
=
=

Ry1
S(1)ac1==

S(1)de1

=

Sde1
TB
T(1)1

=
=
=

(1)
1

=

B

=

Modal acceleration belonging to first (prevalent) mode
Equivalent yield acceleration belonging to first mode
Spectral displacement ratio belonging to first mode
Modal displacement belonging to first (prevalent) mode
Equivalent yield displacement belonging to first mode
Maximum modal displacement (modal displacement request) belonging tofirst mode achieved at the end of last p’th impulse stepStrength Decrease Coefficient belonging to first mode
Elastic spectral acceleration belonging to first mode at the first step of theimpulse analyze
Linear elastic spectral displacement belonging to first mode at the first step of
the impulse analyze
Nonlinear elastic spectral displacement belonging to first mode
Characteristic period in acceleration spectrums defined in 6.4
Natural vibration period belonging to first vibration mode (prevalent inearthquake direction) in impulse step (i=1)at the beginning
Natural angular frequency belonging to first vibration mode (prevalent inearthquake direction) in impulse step (i=1)at the beginning
Natural angular frequency correspond to characteristic period in acceleration
spectrum defined in 6.4

7C.1. Linear and Non - Linear Spectral Replacements
Non - linear inelastic spectral replacement, Sdi1 , in the first step of the drift analysis, shallbe obtained with Equation (7C.1) depending on the linear elastic spectral
replacement Sde1 which corresponds to T1(1) beginning period regarding the first (dominant)mode calculated as based on linear elastic behavior:
Sdi1 = CR1 Sde1

(7C.1)

Linear elastic spectral replacement Sde1 is calculated from elastic spectral acceleration
Sae1 regarding first mode in the first step of drift analysis:

Sde1 =

Sae1( 1(1) ) 2(7C.2)

7C.2. Ratio of Spectral Replacement
Ratio of spectral replacement CR1, in Equation (7C.1) is determined according to 7C.2.1
or 7C.2.2 depending on the value (T1(1) = 2π / 1(1) ) of starting period T1(1) .

7C.2.1 – In case where the starting period T1(1) is equal to or more than the characteristic
period TB in the acceleration spectrum defined in 2.4, ( T1(1) ≥ TB or ( 1(1) ) 2 ≤2B ), non -linear inelastic spectral replacement Sdi1 is taken as equal to Sde1 linear elastic spectral
replacement regarding also the conjugated linear elastic system which’s natural period is
also T1(1) in accordance with equal replacement rule. Accordingly, spectral replacement
ratio in Equation (7C.1) is as follows:142CR1 = 1(7C.3)In Figure 7C.1 and following Figure 7C.2, model capacity diagram that the coordinatesare (d1, a1) and belong to first (dominant) vibration mode and behavioral spectrum that thecoordinates are “spectral replacement (Sd) – spectral acceleration (Sa)” are drawn
together.

7C.2.2 – In case where the starting period T1(1) is less than the characteristic period TB in
the acceleration spectrum defined in 2.4, T1(1) < TB or ( 1(1) ) 2 > 2B ), spectral replacement
ratio CR1 in Equation (7C.1) shall be calculated with successive approach method as
follows:
a1, Saω2B =(2π/TB ) 2

Sae1(ω1(1) ) 2

d1(p) = Sdi1 = Sde1

d1, SdFigure 7C.1(a) Modal capacity diagram obtained as a result of drift analysis, as shown in Figure 7C.2(a), is is turned approximately into a bilinear diagram. Slope of the starting line of thisdiagram is taken as equal (T1(1)=2π /ω1(1)) with Eigen value (ω1(1))2,ertaining to the firstmode that is the slope of the line in the first step (i=1) of drift analysis.

(b) As accepted CR1 = 1 in the first step of successive approach, in other words by using
Equation (7C.3) coordinates of equivalent yield point is determined with equal areas rule.
CR1 is defined as follows as based a yo1 seen in Figure 7C.2 (a):CR1 =

1 + (Ry1 − 1) TB / T1(1)
Ry1

≥ 1

(7C.4)In this correlation, Ry1 indicates the strength reduce factor pertaining to first mode:

Ry1 =

Sae1
ay1

(7C.5)

143

(c) By using CR1in Equation (7C.4), coordinates of equivalent yield point is re-determinedwith equal areas rule by taking Sdi1 calculated according to Equation (7C.1) as basis, as
shown in Figure 7C.2 (b) and accordingly ay1, Ry1 and CR1 are calculated again. When the
results obtained from successive two steps reasonably close up then the successive
approached is concluded.
a1, Sa
Sae1

(a)

o
ay1

( 1(1) ) 2
Sded1, SdSdi1

a1, Sa
Sae1

(b)

ay1
o
ay1

( 1(1) ) 2
Sde1 d1(p) = Sdi1

d1, SdFigure 7C.2

144

INFORMATION ANNEX 7D
IMPULSE ANALYZE WITH INCREMENTAL MODE COMBINATION
7D.0. NOTATION= Modal acceleration belonging to n’th mode at the end of (i)’th impulse step.
an(i)
ayn
= Equivalent outflow acceleration belonging to n’th modeCRn
= Spectral displacement ratio belonging to n’th moded n(i) = Modal displacement belonging to n’th mode at the end of (i)’th impulse step

F (i)
(i)
M j,x

=
=

Cumulative scale factor belonging to (i)’th impulse step
Bending moment formed around the x axis in (j) plastic cross section at the end=of (i)’th impulse step,
Bending moment calculated around the x axis in (j) plastic cross section at the=(i)’th impulse step, in the result of linear mode combination analyze withtaking ∆F (i) =1 .
Bending moment formed around the y axis in (j) plastic cross section at the=end of (i)’th impulse step,
Bending moment calculated around the y axis in (j) plastic cross section at themsN j(i)==(i)’th impulse step, in the result of linear mode combination analyze withtaking ∆F (i) =1 .
Mass of any (s) degrees of freedom
Axial force formed in (j) plastic cross section at the end of (i)’th impulse step

N j(i)=

Axial force calculated in (j) plastic cross section at the (i)’th impulse step, in==

the result of linear mode combination analyze with taking ∆F (i) =1
Strength Decrease Coefficient belonging to n’th mode
Typical displacement, plastically deformation or internal force which are=formed in any (j) point or cross section at the end of (i)’th impulse step
Typical displacement, plastically deformation or internal force calculated in (j)

(i)
M j,x

(i)
M j,y
(i)
M j,y

Ryn
rj(i)
rj(i)

(1)
Saen

=

(1)
Sden

=

TB
Tn(1)

=
=

α jk,x=point or cross section at the (i)’th impulse step, in the result of linear mode
combination analyze with taking ∆F (i) =1 .
Elastic spectral acceleration belonging to n’th mode in the first step of theimpulses analyzes.
Linear Elastic spectral displacement belonging to n’th mode in the first step of
the impulses analyze
Characteristic period in acceleration spectrum defined in 6.4’de
Natural vibration period belonging to n’th vibration mode in the impulse stepat the beginning (i=1)
Coefficient which is defining (k)’th yield platform or line concerning with the=moment around the x axis in (j) plastic cross section
Coefficient which is defining (k)’th yield platform or line concerning with the=moment around the x axis in (j) plastic cross section
Coefficient which is defining (k)’th yield platform or line concerning with theα jk,yβ jkaxial force in (j) plastic cross section145∆an(i)∆d n(i)∆F (i)
fsn(i)

=
=
=
=

(i)
=
usn

(i)
sn

=

(i)
xn

=

B

=

(i)
n

=

(1)
n

=

(p)
n

=

Modal acceleration increase belonging to n’th mode in the (i)’th impulse step
Modal displacement increase belonging to n’th mode in the (i)’th impulse step
Increasing spectrum scale coefficient in the (i)’th impulse step
Increasing of the displacement effecting any (s) degrees of freedom of thesystem for n’th natural vibration mode in the (i)’th impulse step
Increasing of the earthquake load effecting any (s) degrees of freedom of thesystem for n’th natural vibration mode in the (i)’th impulse step
Amplitude belonging to (s) degrees of freedom of n’th mode figure which was
determined by considering plastic cross section configuration in that step at the(i)’th impulse step
Contribution factor belonging to n’th natural vibration mode for theearthquake in x direction at the (i)’th impulse stepNatural angular frequency correspond to TB characteristic period inacceleration spectrum defined in 6.4’de
Natural angular frequency belonging to (s) degrees of freedom of n’th mode
figure this was determined by considering plastic cross section configurationin that step at the (i)’th impulse stepNatural angular frequency belonging to n’th vibration mode in the impulse stepat the beginning (i=1)
At the last impulse step (i=p)

7D.1. Introduction
7D.1.1 – The most significant disadvantage of conducting repulsion analysis using theIncremental Equivalent Seismic Load Method explained in 7.6.5 is the assumption
proposing that the seismic behavior of the load-bearing system is solely composed of the
behavior in the primary (dominant in the seismic direction) natural vibration mode. Due tothis reason, the applicability of the method is limited to the few-floor buildings and thebuildings that are symmetric or nearly symmetric to the seismic direction according to theplans. Although various repulsion analysis methods that can be applied to the buildings that
doesn’t satisfy these conditions as they consider multiple vibration modes are proposed, themajority of these deal only with determining the global strength and deformation capacitiesof the load-bearing system. There are a limited number of methods that aim at deriving thevolition values required to make performance evaluation under the effect of a certain
earthquake [1–5] ∗. By means of the Incremental Mode Combination Method
explained in this Information Appendix, the contributions of individual modes to theformation of each plastic section can be considered in the repulsion analysis [4, 5], and theplastic rotations and inner force volitions can directly be derived without requiring any
additional analysis.
7D.1.2 – In repulsion analyses conducted under Incremental Mode Combination Method,“step-by-step linear elastic” behavior in each repulsion step between the plastic section
formation between two subsequent sections is taken as a basis. Considering the modaltranslocations monotonically increased via modal scaling, a linear behavior spectrum ineach step of which mode combination rules are applied is obtained. Utilizing the results ofthis analysis, the plastic section formed at the end of the step is determined andtranslocation, plastic deformation and inner force increments together with the incremental
values corresponding to these increments and thus the maximum values corresponding to
the seismic volition are calculated [4, 5].

146

7D.2. Modal scaling
7D.2.1 – The translocation increment in an (i)th linear repulsion step in the formation of
two subsequent plastic sections for any independence level (s) for a typical nth natural
vibration mode can be written as the following:
(i)
(i)
(i)
= sn
(7D.1)usn
d n(i)
xn
7D.2.2 - With adding the ∆d n(i) that represents modal replacement increase in the (n)th atthe(i)th drift step and located in Equation (7D.1) to the modal replacement at the end of theprevious drift step, cumulative modal replacement at the end of the (i)th step is obtained asfollows:(7D.2)
d n(i) = d n(i−1) + ∆d n(i)In order to consider relative contributions of the modes, according to equal replacement rule
pertaining to single degree of freedom system, cumulative modal replacement, is defined(1)in the first step (i= 1) at the same mode:
proportionally to elastic spectral replacement Sden(1)d n(i) = Sden
F (i)(7D.3)

Here F (i) indicates the cumulative spectrum scale factor which is considered as constant for
all modes in the (i)th drift step. As a result of Equation (7D.2) and Equation (7D.3), modal
replacement increase in the nth mode is defined as follows:(1)∆d n(i) = Sden
∆F (i)(7D.4)

Here ∆F (i) is also indicates the incremental spectrum scale factor which is considered as
constant for all modes in the (i)th drift step. Thus, all modal replacement increases are figured
with single parameter. Relation between incremental and cumulative spectrum scale factors
are formulated as below:(7D.5)
F (i) = F (i−1) + ∆F (i) ≤ 1(1)
Sden Elastic spectral replacement defined for the first (i= 1) drift step at the above
correlations can be obtained from elastic spectral replacement defined according to 2.4 forthe same step:
(1)
Saen
(1)
(7D.6)
Sden = (1) 2( n )7D.2.3 – Modal scaling correlations given with Equation (7D.3) and Equation (7D.4),
correspond to monolithically increasing elastic spectral replacement during each drift step
where a new plastic section formed. In other words, seismic effects in terms of spectral
replacements are increased in definite amount in the each drift step starting from zero.
a, Sa

n=
n=
Last stepn=2
Mid - StepFirst plastic
section step

n=1

d, Sd
1477D.1
Figure147

At the end of the linear elastic first step where first plastic section in the system is formed
scaled condition of behavioral spectrum (F (1) ≤ 1) drawn at the coordinates of “spectral
replacement (Sd) – spectral acceleration (Sa)” by using Equation (7D.6) is shown in
Figure 7D.1. Scaled condition of spectrum at the end of any following (i)th inter - step(F (i) ≤ 1) is also seen similarly. At the end of the last step of (p)th drift, in accordance withthe equal replacement rule, elastic behavioral spectrum is obtained (F (p) = 1). Also modal
capacity diagrams to be obtained below and defined with the coordinates of “Modal
replacement (d) – modal acceleration (a)” are schematically shown in Figure 7D. 1 forthe first four mode of a considered typical structural system

7D.3. Drift Analysis Algorithm with Incremental Mod Combination Method
By grounding the modal scaling transaction defined above, main steps of the drift analysis tobe applied with incremental mode combination method are summarized below:

7D.3.1 – In the practical implementation of the Incremental Mode Combination Method,linear Mod Combination Analysis is made by taking ∆F (i) = 1 in the each (i)th drift step. In
the analysis, by grounding the axial forces at the end of the previous step, effects of second
stage can be taken into consideration. Number of mode to be considered is determinedaccording to 2.8.3 as based on the biggest modals in the first drift step (i=1). In this analysis;(1)(a) According to Equation (7D.1) and Equation (7D.4), elastic spectral replacement Sdenin the first drift step (i=1) is taken into account as an earthquake data for a typical nth mode.
This introduction information is used exactly in all drift steps without any change.
(b) For the calculations of all replacements, deformations, modal contributions to internal
force magnitudes, Complete Quadric Combination Rule (CQC) specified in 2.8.4 is applied.
In the implementation of this rule, critical damping ratio is taken as 0.05 in all modes.
7D.3.2 – At the end of any (i) th drift step between sequential two plastic section, typicalmagnitude rj(i) represents any replacement, plastic deformation or internal force formed inany (j) point or section of the structural system is formulated in terms of incremental scale
factor ∆F (i) pertaining only to (i)th step as unknown as below:(7D.7)
rj(i) = rj(i −1) + rj(i) ∆F (i)Definitions concerning this correlation are given below:(a) At the end of a linear mod combination analysis made according to 7D.3.1 in the (i) th
drift step by taking ∆F (i) = 1 , rj(i) represents a typical replacement, plastic deformation orinternal force calculated in the (j) point or section. Because the indicators became
disappeared due to the implementation of Complete Quadric Combination (CQC) modal
combination rule; indicator in the mode where the biggest absolute value is obtained fromtypical replacement, plastic deformation or internal force is taken into account.
(b) rj(i) represents the typical magnitude to be obtained according to 7D.3.5 after the
calculation of ∆F (i) according to 7D.3.4 at the end of (i) th drift step. Whereas rj(i −1) shows

the magnitude obtained at the end of the previous (i - 1)th drift step. In this context, step zero(i–1=0), which is before the first drift step (i=1) corresponds to the typical magnitude
obtained from the gravity load analysis that is necessarily made before the drift analysis.

148

7D.3.3 – General correlation given in Equation (7D.7) in the each drift step is speciallywritten for the bending moment in every potential plastic section in the beams, for theinternal forces that form the coordinates of yield surface in the columns and walls. For thebiaxial bending and axial force in three - dimensional behavior condition:(i)(i −1)(i)∆F (i)= M j,x+ M j,xM j,x(i)(i −1)(i)∆F (i)= M j,y+ M j,yM j,y(7D.8)

N j(i) = N j(i −1) + N j(i) ∆F (i)7D.3.4 – In case of a three - dimensional behavior as considered generally, analyticalformulation of the (k)th plane part that corresponds any of the yield surfaces linearizedaccording to 7.6.4.5 in the section (j) is formulated as follow:

α jk,x M j,x + α jk,y M j,y + β jk N j = 1(7D.9)

With placing the magnitudes in Equation (7D.8) to Equation (7D.9), incremental scale
factor pertaining to (i)th step is calculated without the need of successive approach:(i)(∆F ) jk =(i −1)(i −1)− α jk,y M j,y− β jk N j(i −1)
1 − α jk,x M j,x(i)(i)
α jk,x M j,x+ α jk,y M j,y+ β jk N j(i)(7D.10)In any of (j) potential plastic section, after finding the positive and smallest (∆F (i) ) jk values
obtained for all (k) yield surfaces (lines), the smallest one of them calculated in the structural
system is obtained as the ∆F (i) incremental scale factor at the end of (i)th step. And thesection (j) which is corresponding to this value is determined the place of the newly
established plastic section in the system.

7D.3.5 – After obtaining ∆F (i) in the (i)th drift step;(a) Cumulative spectrum scale factor F (i) is calculated from the Equation (7D.5).
(b) rj(i) , any typical replacement, plastic deformation or internal force magnitude formed in
the any (j) point or section of the structural system is obtained according to Equation (7D.7).
(c) Modal replacement increments pertaining to considered all modes are calculated from
Equation (7D.4). Cumulative modal replacements at the end of the (i)th drift step arecalculated from Equation (7D.2) or Equation (7D.3).

7D.3.6 – Modal acceleration increments pertaining to all modes in the (i)th step are calculatedwith the following correlation:2(i)∆an(i) = ( (i)(7D.11)n ) ∆d n
However not used directly from the formulation of the Incremental Mode Combination
Method as stated here, as a description, modal seismic load increment fsn(i) that affects the (s)freedom degree in the (n)th mode is given above depending on the modal acceleration
increment ∆an(i) :fsn(i) = ms

(i)
sn

(i)
xn

an(i)

(7D.12)

Cumulative modal acceleration values at the end of the (i)th drift step are calculated with the
below formula:an(i) = an(i −1) + ∆an(i)(7D.13)149

7D.3.7 – Typical modal capacity diagrams in which modal replacements are indicated inhorizontal axis and modal accelerations are indicated in vertical axis is shown in Figure
7D.1. As a description, slope of a line section between two sequential plastic sections in the
typical capacity diagram pertaining to nth mode is equal to the square of the natural angular2frequency of the nth mode in that step in accordance with the Equation (7D.11) ( (i)n ) , inthother words, equals to n Eigen value. As a result of the spread of the plastic replacements,
Eigen values of some modes due to the effects of second stage, accordingly the slopes therelevant modal capacity diagrams can take negative values after a definite drift step. It should
be taken into consideration that the effects of second stage can change the shapes of modes.
Whereas its effects on the modal seismic prompts are generally in allowable levels
7D.3.8 – After the completion of a drift stage, by considering the plastic section formed at
the end of that stage, necessary changes are made in the rigidity matrix of system andtransactions are started for the new drift stage. 7.6.4.7 Should be considered in the drift
stages that follow the plasticity in the sections under the effects of uniaxial or biaxial
bending or axial forces.
7D.4. Determination of Prompt Magnitudes
7D.4.1– Modal replacements in the Incremental Mod Combination Method reaches theirmaximum values with all other modes. At the end of each drift step, it is controlled
whether the cumulative spectrum scale factor which is calculated with Equation (7D.5)
exceeds the unit value as a maximum value or not. In case of non - exceedance, theanalysis continued as defined above. In case of an exceedance;(a) The obtained drift stage is defined as the last stage and represented by (p) superscript.
Taking i = p, and considering F (p) = 1 , incremental spectrum scale factor concerning thelast stage is calculated with Equation (7D.5):∆F (p) = 1 − F (p −1)(7D.14)(b) However it is necessary to re - define the modal replacement in the nth mode definedwith Equation (7D.4) at the last drift stage as follows:(1)∆d n(p) = CRn Sden
∆F (p)(7D.15)(1)
In any of the mode in case CRn > 1 according to 7D.4.2, CRn Sden
is taken as data for(1)earthquake instead of Sden
in 7D.3.1 and with the Method of Mod Combination rj(p) value

pertaining to typical magnitude is re - calculated.

(c) Maximum value of typical replacement, plastic deformation and internal force, in otherwords typical prompt magnitude are obtained according to Equation (7D.7):
rj(p) = rj(p −1) + rj(p) ∆F (p)(7D.16)th

7D.4.2 – CRn spectral replacement ratio regarding any considered n mode is calculated asfollows:2(a) In case the condition Tn(1) > TB [or ( (1)n ) <2(b) In case where Tn(1) < TB [or ( (1)n ) >follows:

λ (p)
n =

2
B ] is covered then CRn = 1 is taken.

2
B ] then CRn can be approximately determined as

2
( (p)
n )
;
2
( (1)
)
n

150

CRn =

1 + (Ryn − 1) TB / Tn(1)Ryn≥1

1 + (Ryn − 1) TB / Tn(1)CRn =≥110 λ (p)n Ryn(λ (p)n ≤ 0.10)(7D.17)(λ (p)
n > 0.10)

In this correlation Ryn, indicates the strength reduce factor obtained from the bilinear
modal capacity diagram drawn for n’th mode:
Ryn =

(1)
Saen
ayn

(7D.18)Related to the successive approach concerning bilinear modal capacity diagram, theapproach given for the first mode (dominant) and Information Annex 7C are useful (SeeFigure 7C.2).

7D.5. Special Conditions
7D.5.1 – If it is assumed that solely the primary (dominant in the earthquake direction) mode has
impact on the load-bearing system behavior, all of the equations given below regarding theIncremental Mode Combination Method can only be used for the dominant mode, without
introducing any modifications. The repulsion analysis for this special condition is reducedin the single-mode repulsion analysis in which the load distribution in every repulsion stepis assumed to be variable for the Incremental Equivalent Seismic Load Method according
to 7.6.5.5. For this solution in which the modal scaling is not considered, the magnitudes
obtained during all repulsion analysis steps before the final step where i = p are independentof the earthquake selected.
7D.5.2 – In case the load-bearing system behavior is linear elastic, Incremental Mode
Combination Method is reduced to the linear Mode Combination Method. Since the modaltranslocation volition will be obtained without any plastic deformation coming out as theyield surfaces are fictitiously expanded, the repulsion analysis in such a case will terminate
after a single step and the modal capacity diagrams given in Figure 7D.1’will consist onlyof line segments for each.
7D.6. References[1] Chopra, A.K, Goel, R.K (2002). A modal pushover analysis for estimating seismic
demands for buildings, Earthquake Engineering and Structural Dynamics; 31(3): 561-582.
[2] Goel, R.K, Chopra, A.K, (2004). Evaluation of Modal and FEMA Pushover Analyses:
SAC Buildings. Earthquake Spectra; 20(1): 225–254.
[3] Goel, R.K, Chopra, A.K, (2005). Extension of Modal Pushover Analysis to compute
member forces, Earthquake Spectra; 21(1): 125–139.
[4] Aydıno lu, M. N. (2003). An incremental response spectrum analysis based oninelastic spectral displacements for multi-mode seismic performance evaluation. Bulletinof Earthquake Engineering; 1(1): 3–36.
[5] Aydıno lu, M. N. (2004). An improved pushover procedure for engineering practice:
Incremental Response Spectrum Analysis (IRSA). International Workshop on Performance- based Seismic Design: Concepts and Implementation, edited by P. Fajfar and H.
Krawinkler, Bled, Slovenia, 28 June – 1 July 2004, Pacific Earthquake Engineering Center,
University of California, Berkeley, PEER Report 2004/05: 345–356

151

INFORMATION ANNEX 7E
INCREMENT CALCULATION OF STRENGTH AND DUCTILITY IN THE
COULMNS COATED WITH FIBER POLYMER
7E.0. NOTATIONS
As
b
bw
d
d′
Ef
fcc
fcm
fym
h
fhs
fl
Ls
n
nf
p
rc
sf
tf
Vc
Vf
Vmax
Vr
Vs

=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=

wf

=
=
=
=
=
=
=

cc
f
fu

κa
φ
f

Column reinforcement area (for single bar)
Width of the horizontal plates.
Cross section body width
Effective height of the cross section
Thickness of the corrosion allocation.
Elasticity module of the fibrous polymer
Compressive strength of the concrete enswathed with fibrous polymer.
Compressive strength of the existing concrete defined according to 7.2
Outflow strength of the existing steel defined according to 7.2
Dimension of cross section in the direction ofTension defiant 0.001 unit lengthening in transversely reinforcement
lateral pressure provided by fibrous polymer
Existing overlap length
Number of overlapped reinforcement
LP winding plate number in one side
Perimeter of core cross section
Truncation radius made in the corners
Distance of the fibrous polymer band from axis to axis
Effective thickness for one plate of fibrous polymer
Contribution of the concrete to the shearing force strength
Contribution of the fibrous polymer to the shearing force strength
Shearing force defined in order to limit main pressure tensions
Shearing strength of the column or cross section
Contribution of the transversely reinforcement to the shearing powerstrength
Width of the fibrous polymer band
Unit shortening correspond to coated concrete pressure strength
Effective unit lengthening limit of the fibrous polymer
Breaking unit lengthening of the fibrous polymer
Cross section figure coefficient of performance
Diameter of reinforcement
Volume ratio of the fibrous polymer

7E.1. Increasing the Shearing strength of the Columns
Shearing force strength of column and beams coated with FP is calculated with Equation(7E.1).
Vr = Vc + Vs + Vf ≤ Vmax

(7E.1)

Values of the concrete contribution to shearing force strength Vc , contribution of transverse
reinforcement Vs and Vmax defined in order to limit principle pressure tensile shall becalculated only with current material strengths determined according to 7.2 with the
Equation suggested by TS - 500. In case the coating realized with strips, contribution of FP
coating Vf to shearing force strength shall be calculated with Equation (7E.2).

152

Vf =

2 nf tf wf Ef εf d
sf

(7E.2)In Equation (7E.2), nf indicates the number of FP coating layers on one side, tf indicateseffective thickness for one FP layer, wf indicates the width of the FB strip, Ef indicates theelasticity modulus of FP, εf indicates the effective unit extension boundary of FP, d
indicates the useful height of element, and sf indicates spaces of FP strips from axis to axis
(Figure 7E.1). In case the coating is made continuously, wf = sf is taken. Effective unit
extension value is taken according to Equation (7E.3).
f ≤ 0.004(7E.3)

f ≤ 0.50 fu

In the Equation (7E.3) εfu is the unit breaking strain of FP. In case transient FB is used (instrips), spaces of FP strips sf shall not exceed ( wf + d 4) value.
rc

Tabla

Lifli
polimertam sargı

d
sf

wf

a) Kolonlarb) Kiri ler

Figure 7E.1
7E.2. Increasing the Axial Pressure Strength of Columns
In order to increase axial pressure strengths of the columns with FP coating, ratio of thelong dimension of column section shall not more than two times the short dimension of thecolumn section. By turning the cross - sections of columns from rectangular to ellipse
effectiveness of the FB may be increased. Ratio of long dimension to short dimension in
may be maximum three in ellipse sections. While calculating axial load strength of acolumn coated with FP, fcc value determined with Equation (7E.4) shall be used instead offcd for the pressure strength of the concrete.

f cc = f cm (1+2.4 (f1 / f cm ) ) ≥ 1.2 f cm

(7E.4)In the Equation (7E.4) f cm is the current pressure strength of un - coated concrete and f l is
the lateral pressure amount provided by FP coating. f l shall be calculated according toEquation (7E.5).
1(7E.5)fl =a f f Ef
2
In the Equation (7E.5) εf shall be calculated with Equation (7E.3). In this Equation a isthe effectiveness factor of section shapes, and ρf is the volumetric ratio of Fp.
for several sections in Equation (7E.6).

ais given

153

1
a=

Dairesel kesitbh(7E.6)

Elips kesit(b − 2rc ) 2 + (h − 2rc ) 2
1−
Dikdörtgen kesit
3b h
B and h shown in Equation (7E.6) are the lengths of the short and long sides forrectangular cross sections, relevant dimensions for the short and long sizes of elliptic crosssections and rc is the radius of rolling in rectangular cross sections (Figure 7E.2).
b

b
rc

rc
h

h

rc

h

Dolgu
beton

a)Dairesel Kolonb) Dörtgen Kolonc) Eliptik Kolon

ekil 7E.2
7E.3. Increasing the ductility of columns
In order to increase the ductility of columns via FP coiling, the ratio of the length of thelong edge of the column to that of the short edge should not be higher than two. This ratio
can not be higher than three in elliptic cross sections. Unit shortening (εcc) that coincides
with the concrete pressure tolerance in a column that is coiled via FP can be determined by
Equation (7E.7).

ε cc = 0.002 (1 + 15(f1 / f cm )0.75 )(7E.7)

fl in Equation (7E.7) shall be calculated by Equation (7E.5). In order to increase theductility via FP coiling the minimum tolerance increase determined by Equation (7E.4)
shall be maintained.

(a) While using linear elastic calculation methods, whenever the εcc value of any column,
as calculated by Equation (7E.7), is greater than 0.018, the column is accepted as coiled;otherwise it is accepted as uncoiled.
(b) For linear inelastic calculation methods, while obtaining the momentum-curvature
relation of the FP coiled cross sections, an idealized stretching-deformation relation thatshall be composed of two lines may be used for the FP coiled concretes. The stretchingand deformation values of this relation can be taken as fc (capacity) and 0.002. Values atthe last point of the stretching-deformation relation are calculated by Equation (7E.4) andEquation (7E.7). In the FP coiled armored concrete carrier system elements, where plastic
deformation has occurred, maximum concrete unit shortening value for the cave in the
cross section is equal to the value calculated by Equation (7E.7), that for the security limit
is 75% of to the value calculated by Equation (7E.7) and minimum damage limit shall betaken as 0.004 depending on the performance levels. These values and the unit lengthening
values of the equipment steel can not exceed the upper limits set in 7.6.9.
154

7E.4. Coating for Insufficient Overlapping Length in the Columns
Because coating effect is insufficient for the columns that the section length ratio is morethan two or the columns that the longitudinal reinforcements are smooth surface,strengthening of the overlapping zones can not be made with FP coating. Necessary FP
thickness for covering insufficiency of overlapping length on the columns of whichlongitudinal reinforcements are ribbed shall be calculated according to Equation (7E.8).
tf =500 bw ( f k − f h s )(7E.8)
Ef
In the Equation (7E.8) bw is the width of the section, f h s is the tensile that corresponds
0.001 unit extension in the transverse reinforcement. κa factor should be calculated
according to Equation (7E.6) for different sections. In the Equation (7E.8) f k value shallbe calculated according to Equation (7E.9).
As f ymfk =(7E.9)p+ 2(φ + d ′) Ls
2n
In the Equation (7E.9) As is the area of column reinforcement (for single strip), fym is theyield strength of current reinforcement, p is the periphery of core section, n is theoverlapped reinforcement number, φ is the diameter of reinforcement, d ′ is the thicknessof rust and L s is the existing overlapping length.

155

INFORMATION ANNEX 7F
METHODS FOR STRENGTHENING OF THE INFILLED WALLS
7F.0. NOTATIONS
Awall
awall
Ec
Edp
Ewall
fdp
fwall
fyd
hwall
Ik
kwall
kt

=
=
=
=
=
=
=
=
=
=
=
=

lmin
rwall
smax
tdp
twall
Tf

=
=
=
=
=
=

tf
Vwall
ømin

=
=
=
=
=

wall
sh

θi
wall
dp

=
=
=

Horizontal cross section area of the filling wall
Width of the equivalent pressure bar (mm)Elasticity module of frame concrete
Elasticity module of the prefabricate concrete wall panel
Elasticity module of filling wall
Pressure strength of the prefabricate concrete wall panel
Pressure strength of filling wall
Design yield strength of the mesh reinforcement steel
Height of the filling wall (mm)
Inertial moment of the column (mm4)Axial rigidity of the equivalent pressure bar
Axial rigidity of the wall drawbar which was strengthened with fibrous
polymer
Minimum depth of anchorage bar
Diagonal length of filling wall
Maximum distance of anchorage bar
Thickness of the prefabricate concrete wall panel (mm)Thickness of the filling wall
Tensile strength of the wall drawbar which was strengthened with fibrous
polymerThickness of the fibrous polymer
Shearing force strength of the filling wall
Minimum diameter of anchorage bar
Coefficient of equivalent pressure bar
Ratio of horizontal body reinforcement in the curtain and wall to the brutcross sectional area of curtain bodyAngle of equivalent pressure bar with horizontal one
Sliding strength of the filling wall
Sliding strength of the prefabricate concrete wall panel

7F.1. Strengthening the Filled Walls
The rigidity and the shear strength of the filled walls in the reinforced concrete frame that iscontinuous beginning from the top of grounding up to the top may be improved using themethods given below provided that the methods are applied as per7.10.4 to at most threefloor buildings excluding the basement floor.
7F.2. Strengthening the Filled Walls using Matted Steel Reinforced Special Plaster
The rigidity and the shear strength of the filled walls can be improved with special-mixture
matted steel-reinforced plaster layer to be applied on the wall surface.
(a) The thickness of the plaster layer should be minimum 30 mm and the rust space of thematted reinforcement should be minimum 20 mm. Special-mixture plaster will be made with4 volume sand, 1 volume cement and 1 volume lime mixture. The pressure strength of theplaster made in this mixture composition will be minimum 5.
(b) The ratio of the diagonal length of the wall to be strengthened to the thickness before thestrengthening is applied should be lower than 30. For this type of applications, formation ofpressure stick in the existing frame should be ensured and the anchors necessary to maintainthe load transfer to the frame should be designed. Because of this requirement, there shoulda splicing of at least 30 mm deep between the wall surface the application will be made on
and the outer surface of the frame components (Figure 7F.1). Otherwise, this type of wallstrengthening cannot be applied.
156

(c) The minimum value of the diameter of the frame anchoring stick that will be used
between the reinforcement - plaster layer and the frame components should be 12 mm,
minimum anchor depth should be ten times of the stick diameter and the widest stick
splicing should be 300 mm. Moreover, so as to enable the reinforced plaster layer and theexisting filled wall to work together, body anchoring perpendicular to the wall axis should
be applied as four anchors per one square meter wall area. The body anchoring sticks to be
applied perpendicular to the wall will be buried in the mortar joints of the filled wall
provided that the minimum diameter of the stick of 8 mm and the anchoring dept will be atleast ten times of the stick diameter. All anchor sticks applied perpendicular or parallel to thewall axis will be implemented in the holes to be born with an epoxy - based material and theedges will be put through the matted reinforcement, bending the edges 90˚ to become in L
shape. The details on the application are shown in Figure 7F.1.
(d) To enable the forces arising in the strengthened filled walls to be transferred to the ground,
required grounding arrangement should be implemented. The walls strengthened with matted
steel reinforcement will be included in the structure model in accordance with the principles
given below.
7F.2.1 – Modeling Principles: The rigidity and strength features to be used so as for thefilled walls strengthened with matted steel reinforcement to be represented in the structure
model are defined below. Filled walls that are designed in reinforced concrete frames andthe ratio of the diagonal length to the thickness for which is below 30 will be taken into
consideration in the structural modeling. The walls that include splicing the ratio of which towall surface doesn’t exceed 10 % may be included in the structure modeling provided thatthe positions of the splicing don’t block the formation of diagonal pressure stick. Filled walls
strengthened with matted steel will be represented with equivalent diagonal stickcomponents that receive pressure force in the direction that the earthquake is applied.
(a) Rigidity: The thickness of the equivalent pressure stick is equal to the thickness of thestrengthened filled wall. The width awall will be calculated using Equation (7F.1).
(7F.1)
a wall = 0 . 175 ( λ wall h k ) − 0 , 4 r wall
In this formulation, awall is the width of the stick (mm), hc is the length of the column (mm)and wall is the diagonal length of the filled wall (mm). λwall will be calculated using
Equation (7F.2).
λ wall =E wall t wall sin 20
4 E c I k h wall

1
4

(7F.2)In Equation (7F.2), Ewall and Ec represent the elasticity module of the filled wall and theframe concrete, twall and hwall represents the thickness and the height of the strengthened wall(mm), Ik represents the inertia momentum of the column (mm4) and θ represents the angle
between the diagonal and the horizontal surface. The axial rigidity of the diagonal pressure
stick will be calculated using Equation (7F.3).
k wall =a wall t wall E wall
rwall

(7F.3)

Shear Strength: The horizontal component of the equivalent pressure force strength of the
diagonal stick will be considered as the shear force of the filled wall strengthened withmatted steel reinforcement. The shear strength of the filled wall, Vwall, with horizontal section
area Awall, pressure strength fwall and shear strength τwall will be calculated with Equation(7F.4).
V wall= A wall ( τ wall

+ f yd ρ sh ) ≤ 0 . 22 A wall

f wall(7F.4)
157

Here fyd represents the design yield strength of the matted reinforcement, and sh represents
the ratio of the horizontal body reinforcements of the wall to the gross cross section area.
Matted reinforcement should have the same reinforcement area in horizontal and verticalaxes.

7F.2.2 – Material Qualifications: The recommended values for filled walls built withdifferent types of bricks in accordance with the Ewall, fwall and τwall mentioned above are
given below. The composite sectional structure of the strengthened wall can be considered inpressure and shear forces of the elasticity module.
Manufactured air brick:Ewall = 1000 MPa; fwall = 1.0 MPa; τwall = 0.15 MPa
Blend brick:Ewall = 1000 MPa; fwall = 2.0 MPa; τwall = 0.25 MPa
Gas concrete:
Ewall = 1000 MPa; fwall = 1.5 MPa; τwall = 0.20 MPa(7F.5a)(7F.5b)(7F.5c)

A
Sıva
Kiriş

l
s
A

l

Çerçeve Ankrajı
Gövde Ankrajı
Yüzey sıvası
Hasır DonatıTuğla duvar

φ min = 12mm
s max = 300mm

A-A Kesiti

l min = 10φ

Figure 7F.1

158

7F.3. Strengthening Filled Walls with Fiber Polymer
The rigidity and the shear strength of the filled walls with length-height ratio between 0.5
and 2 can be improved by means of the fiber polymer (FP) applied to the wall surface.
(a) For these kinds of applications the formation of the pressure stick in the existing frame
should be ensured and anchors required sustain load transfer to the frame should bearranged. For this reason, there should a splicing of at least 30 mm deep between the wall
surface the application will be made on and the outer surface of the frame components.
Otherwise, this type of wall strengthening cannot be applied.
(b) The details regarding the diagonal-fiber polymer straps are shown in Figure 7F.2.
Square FP plates the width of which is not lower than the 1.5 times of the strap width will be
used to ensure the load distribution in the edge zones and to be able to install sufficientnumber of anchors between the reinforced concrete frame and the FP straps. Fiber polymer
will be applied to both sides of the wall and the FP straps will be fixed to the wall by meansof the FP bolts passing through the whole wall thickness. The gap between the FP bolts
cannot be over 600 mm and the distance between the belt and the diagonal strap edge cannot
be over 150 mm. FP anchors will be used to enable the load transfer between the diagonal FP
strap and the frame. FP anchors will be formed via feeding the FP straps with epoxy androlling them around a silicon stick. The end edges of the FP anchors will be given shape of a
fan and minimum 4 anchors will be fitted by injecting epoxy to the dust-free hole, born in theconcrete in a manner that the diagonal will be in the direction of the FP strap. The width of
the FP rolled around the stick to prepare the anchor should not be below 100 mm. thediameter and the width of the anchor hole will not be below 10 mm and 150 mm,
respectively. For the anchor prepared following the way explained, the one smaller in value
among 20 kN and 30 % of the shear strength of the FP rolled around the silicon stick will
be considered as the shear strength.

Figure 7F.2
(c) To enable the forces arising in the strengthened filled walls to be transferred to the ground,
required grounding arrangement should be implemented. The walls strengthened with fiber
polymers will be included in the structure models as per the principles given below.
7F.3.1 – Modeling Principles: The filled walls strengthened with fiber polymer will be
represented in the structure model by the couple diagonal pressure and pulling sticks.
(a) Pressure Sticks: The rigidity and the shear force of the pressure sticks will be calculated
in accordance with 7F.2.1 (a) and (b).
159

(b) Pulling Sticks: Pulling strength of the pulling stick Tf will be calculated using
Equation (7F.6).
T f = 0 . 003 E f w f t f(7F.6)

Shear strength of the pulling stick will be considered as the horizontal component of thepulling strength. Axial rigidity of the pulling stick will be calculates using Equation (7F.7).

kt =wftf E f
rwall(7F.7)

Here, Ef, wf and tf represent the elasticity module, width and the thickness of the fiber
polymer strap, respectively, while rwall represents the diagonal length of the filled wall. The
value taken for wf cannot be bigger than the width calculated using Equation (7F.1).

7F.4. Strengthening the Filled Walls using Prefabricated Concrete Panels
The shear strength and the rigidity of the filled walls can be improved using pre-casting
concrete panel components. This type of strengthening should be applied to the walls forwhich the length-height ratio varies between 0.5 and 2.

(a) Pre-casting panels will be fitted in a way that the panel certainly remains within theframe, they won’t be fitted eccentrically. For this type of applications, formation of pressure
stick in the existing frame should be ensured and the anchors necessary to maintain the loadtransfer to the frame should be designed. Because of this requirement, there should benumber of equal-width splicing that is at least as thick as the wall between the wall surface
the application will be made on and the outer surface of the frame components (Figure
7F.3). Otherwise, this type of wall strengthening cannot be applied.
(b) The ratio of the diagonal length of the walls to be strengthened with prefabricatedconcrete panels to the pre-strengthening thickness should be smaller than 30. Pressure
strength of the pre-casting panel concrete will be minimum 40 MPa. To minimize theshrinkage cracks and the cracks to be possibly formed during the movement, matted
reinforcement in single axis will be put in the middle of the panel. Matted reinforcement ratein each axis will not be below 0.001. Minimum and maximum panel thicknesses will be 40
mm and 60 mm, respectively. The panels will be fitted to the walls using an epoxy-based
adhesive. The adhesive will as well be applied to the areas between the components to bindthe panel components. The strength of concrete adhesion for the epoxy-based adhesive to be
used will be minimum 2.5 MPa. The minimum anchor stick diameter that will be applied
between the pre-casting panels and the frame components will be 12 mm and the anchor
depth will be at least ten times of the stick diameter. The anchors should be applied to alledges of the panels in connection with the frames and will be fitted to the frame using an
epoxy-based adhesive. The panel edges in connection with the anchor should be produced
in a way that it contains gears leaving space for the anchor stick (Figure 7F.3).
(c) Prefabricated concrete panels can be in square or square-like rectangular shape provided
that its weight enables it to be carried easily by two people or can be produced in form ofstraps that can take place among the floors of the building. To enable the forces arising in thestrengthened filled walls to be transferred to the ground, required grounding arrangement should be
implemented. The walls strengthened with prefabricated concrete panels will be included in
the structure model in accordance with the principles given below.

160

7F.4.1 – Modeling Principles: Filled walls that are designed in reinforced concrete frames
and the ratio of the diagonal length to the thickness for which is below 30 will be taken into
consideration in the structural modeling. Filled walls strengthened with prefabricatedconcrete panels will be represented with equivalent diagonal stick components that receive
pressure force in the direction that the earthquake is applied.

Figure F.3(a) Rigidity: The rigidity of the equivalent pressure stick will be calculated as per 7F2.1 (a).
Instead of Ewall and twall, elasticity module and the thickness of the prefabricated concrete
panel Edp and tdp should be substituted in Equation (7F.3). The existing filled wall will not
be included in the calculation.
(b) Shear Strength: The shear strength of the filled wall strengthened withprefabricated concrete panels will be considered as the horizontal component of theequivalent pressure force strength of the diagonal stick. The reinforcement fitted in the panel
components will not be taken into consideration in calculating the shear force of thestrengthened filled wall. Moreover, the existing filled wall will as well not be considered in
the calculation. Shear strength of the strengthened filled wall, Vwall, for which Adp represents
the horizontal section area, fdp represents the pressure strength and τdp represents theslipping strength, will be calculated using Equation (7F.8).
v wall = A dp τ dp ≤ 0 . 08 A dp f dp

(7F.8)

161