NEPAL NATIONAL BUILDING CODE
NBC 205 : 1994

MANDATORY RULES OF THUMBREINFORCED CONCRETE BUILDINGSWITHOUT MASONRY INFILL

Government of Nepal

Ministry of Physical Planning and Works
Department of Urban Development and Building Construction
Babar Mahal, Kathmandu, NEPAL

Reprinted : 2064

NBC108V2.RV9

7 December 1993

NEPAL NATIONAL BUILDING CODE
NBC 205 : 1994

MANDATORY RULES OF THUMBREINFORCED CONCRETE BUILDINGSWITHOUT MASONRY INFILL

This publication represents a standard of good practice andtherefore takes the form of recommendations. Compliance with it
does not confer immunity from relevant legal requirements,
including bylaws
tTsflng >L % sf] ;/sf/ -dlGqkl/ifb\_ sf] ldlt @)^).$.!@ sf] lg0f{ofg';f/ :jLs[tGovernment of Nepal

Ministry of Physical Planning and Works
Department of Urban Development and Building Construction
Babar Mahal, Kathmandu, NEPAL

Reprinted : 2064

NBC108V2.RV9

7 December 1993

i
PrefaceThis Nepal Standard was prepared during 1993 as part of a project to prepare a National
Building Code for Nepal.
In 1988 the Ministry of Housing and Physical Planning (MHPP), conscious of the growing
needs of Nepal's urban and shelter sectors, requested technical assistance from the United
Nations Development Programme and their executing agency, United Nations Centre for
Human Settlements (UNCHS).
A programme of Policy and Technical Support was set up within the Ministry (UNDP Project
NEP/88/054) and a number of activities have been undertaken within this framework.
The 1988 earthquake in Nepal, and the resulting deaths and damage to both housing andschools, again drew attention to the need for changes and improvement in current building
construction and design methods.
Until now, Nepal has not had any regulations or documents of its own setting out either
requirements or good practice for achieving satisfactory strength in buildings.
In late 1991 the MHPP and UNCHS requested proposals for the development of such
regulations and documents from international organisations in response to terms of reference
prepared by a panel of experts.
This document has been prepared by the subcontractor's team working within the Department
of Building, the team including members of the Department and the MHPP. As part of the
proposed management and implementation strategy, it has been prepared so as to conformwith the general presentation requirements of the Nepal Bureau of Standards and Metrology.
The subproject has been undertaken under the aegis of an Advisory Panel to the MHPP.
The Advisory Panel consisted of :Mr. UB Malla, Joint Secretary, MHPP
Director General, Department of Building(Mr. LR Upadhyay)
Mr. AR Pant, Under Secretary, MHPP
Director General, Department of Mines & Geology(Mr. PL Shrestha)
Director General, Nepal Bureau of Standards & Metrology(Mr. PB Manandhar)
MemberDean, Institute of Engineering, Tribhuvan University(Dr. SB Mathe)
Project Chief, Earthquake Areas Rehabilitation &Reconstruction Project
MemberPresident, Nepal Engineers Association
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ChairmanMemberMemberMemberMemberMember
31 October 1994

ii
Law Officer, MHPP (Mr. RB Dange)
MemberRepresentative, Society of Consulting Architectural &Engineering Firms (SCAEF)
MemberRepresentative, Society of Nepalese Architects (SONA)
Deputy Director General, Department of Building,(Mr. JP Pradhan)

MemberMember-Secretary

The Subcontractor was BECA WORLEY INTERNATIONAL CONSULTANTS LTD. of
New Zealand in conjunction with subconsultants who included :Golder Associates Ltd., Canada
SILT Consultants P. Ltd., Nepal
TAEC Consult (P.) Ltd., Nepal
Urban Regional Research, USA
Principal inputs to this standard came from :Dr. AS Arya, University of Roorkee
Mr. JK Bothara, TAEC
Mr. YK Parajuli, TAEC
Mr. AM Dixit, SILT
Mr. AM Tuladhar, DoB, HMGN
Dr. RD Sharpe, BECA (Team Leader)
Revisions and Updated to this code came from:
Mr. Purna P. Kadariya, DG, DUDBC
Mr. Kishore Thapa, DDG, DUDBC
Mr. Mani Ratna Tuladhar, Sr. Div. Engineer, DUDBC
Mr. Jyoti Prasad Pradhan, Ex. DG, DOB
Mr. Bhubaneswor Lal Shrestha, Ex. DDG, DOB
Mr. Uttam Shrestha, Architect, Architects' Module Pvt. Ltd.
Mr. Manohar Lal Rajbhandrai, Sr. Structural Engineer, MR Associates
Mr. Amrit Man Tuladhar, Civil Engineer, DUDBC

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TABLE OF CONTENTS
Preface .......................................................................................................................................................... i0

Foreword ....................................................................................................................................... v
0.1
0.2
0.3
0.4
0.5

1

Scope .............................................................................................................................................. 1
1.1
1.2

2

Description........................................................................................................................ 8
Restrictions on the Structural Layout .......................................................................... 8

Construction Materials............................................................................................................... 10
5.1
5.2
5.3

6

General.............................................................................................................................. 6
Use of Local Knowledge ................................................................................................. 6
Site Investigation Requirements.................................................................................... 6
Allowable Bearing Pressure ........................................................................................... 6

The Building Structure ................................................................................................................ 8
4.1
4.2

5

General.............................................................................................................................. 3
Terminology ..................................................................................................................... 3
Symbols ............................................................................................................................. 5

Selection and Investigation of Site ............................................................................................. 6
3.1
3.2
3.3
3.4

4

General.............................................................................................................................. 1
Related Standards ........................................................................................................... 1

Interpretation................................................................................................................................ 3
2.1
2.2
2.3

3

Introduction ..................................................................................................................... v
Objective ........................................................................................................................... v
Limitations........................................................................................................................ v
Alternative Materials and Construction ...................................................................... v
What is a Pre-Engineered Building ? ........................................................................... vi

Concrete ........................................................................................................................... 10
Brickwork ........................................................................................................................ 10
Reinforcing Steel Bars ................................................................................................... 11

Design Procedure ........................................................................................................................ 11
6.1
6.2

Procedure Outline .......................................................................................................... 11
Total Horizontal Seismic Base Shear........................................................................... 12
6.2.1

6.3
NBC205V2.RV7

Design Seismic Coefficient ................................................................................ 12

Distributing Total Horizontal Seismic Base Shear .................................................... 13
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iv
6.4
7

Distribution of the Seismic Shear to the Individual Frames .................................... 13

Design of the Frames .................................................................................................................. 14
7.1
7.2
7.3

Frames.............................................................................................................................. 14
Frame Analysis ............................................................................................................... 15
Frame Design .................................................................................................................. 15
7.3.1
7.3.2

8

Reinforcing Non-load Bearing Walls ....................................................................................... 25
8.1

Between Framing Columns ........................................................................................... 25
8.1.1
8.1.2

8.2
9

Basis of Recommendations ............................................................................... 15
Recommended Members Sizes and Minimum Reinforcement ................... 16

Solid Walls .......................................................................................................... 25
Walls with Openings ......................................................................................... 25

Outside Framing Columns ............................................................................................ 25

Parapets ........................................................................................................................................ 29
9.1
9.2

NBC205V2.RV7

General............................................................................................................................. 29
Flower Pots ...................................................................................................................... 30

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v
0.

Foreword
0.1

Introduction
For the last 15 to 20 years there has been a proliferation of reinforced concrete(RC) framed buildings constructed in the urban and semi-urban areas of Nepal.
Most of these buildings have been built on the advice of mid-level technicians
and masons without any professional structural design input. These buildings
have been foundto be significantly vulnerable to a level of earthquake
shaking that has a reasonable chance of happening in Nepal. Hence, thesebuildings, even though built with modern materials, could be a major cause ofloss of life in future earthquakes. Upgrading the structural quality of futurebuildings of this type is essential in order to minimise the possible loss of life
due to their structural failure.

0.2

Objective
The main objective of these Mandatory Rules of Thumb (MRT) is to provide
ready-to-use dimensions and details for various structural and non-structuralelements for up to three-storey reinforced concrete (RC), framed, ordinary
residential buildings commonly being built by owner-builders in Nepal. Their
purpose is to replace the non-engineered construction presently adopted withpre-engineered construction so as to achieve the minimum seismic safety
requirements specified by NBC 105 (a draft Nepal Seismic Design Standard).
This MRT is intended to cater primarily to the requirements of mid-leveltechnicians (overseers and draughtspersons) who are not trained to undertake
independently the structural design of buildings. However, civil engineers
could also use this document for effective utilisation of their time by using thedesign procedures outlined here.

0.3

Limitations
The requirements set forth in this standard shall be applicable only forbuildings complying with the specified limitations. The intention is to achievea minimum acceptable structural safety, even though it is always preferable toundertake specific investigations and design. Owners and builders are,however, encouraged to use the services of competent professional designers
for better economy and tailor-made detailing. In such cases, the requirements
stated here could be construed as advisory.

0.4

Alternative Materials and Construction
The provisions of this Standard are not intended to prevent the use ofalternative materials and methods of construction if such materials andmethods are specifically prescribed by competent professional designers orother competent authorities equivalent to, or better than, those specified here.

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0.5

What is a Pre-Engineered Building ?
A pre-engineered building is one which uses the sizes and detailing ofstructural and non-structural elements, including the amounts of reinforcement,
which have been pre-established using standard design procedures for a given
condition. All buildings constructed by following the requirements of thisMRT could, in future, be called pre-engineered buildings.

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1
1

Scope
1.1

1.2

General1.1.1This MRT addresses the particular requirements of those RC-framedbuildings which have become very common with owner-builders, whoeven undertake the construction of this type of buildings without
employing professional designers. However, the users of this MRT are
required to comply with certain restrictions with respect to building
configuration, layout and overall height and size.

1.1.2

The MRT is intended for buildings of the regular column-beam type withreinforced concrete slabs for floors and the roof. The walls are assumed
to be of burnt bricks, or hollow concrete or other rectangular blocks
whose density will not exceed that of burnt bricks. Here, all the
calculations are based on solid clay burnt bricks. These can be replacedby the above described blocks. The buildings have to comply withcertain limitations listed in Clause 4.1, 4.2.

1.1.3

The MRT presents ready-to-use designs for all structural components,
including detailing of structural as well as non-structural members for the
specified building type.

1.1.4

Proportioning of structural components represented in MRT is forordinary residential buildings located in most severe seismic zone
(Figure 1.1).

1.1.5

The building could, of course, be alternatively designed using the usualdesign standards for engineered structures. The design procedures here
are simplified in order both to save design time and to help ownerbuilders to adopt the recommended design and details so that they willachieve earthquake-resistant structures.

Related Standards
The requirements of this MRT are based on the following standards anddocuments. Compliance with this MRT will, therefore, result in compliance withthese Standards :NBC201V2.RV7i)

NBC 110 : (Draft Nepal Standard for Plain and Reinforced Concrete).

ii)

S.P. 16 –1980 : Design Aids for Reinforced Concrete to IS: 456-1978.

iii)

NBC 102/NBC 103 : (Draft Nepal Standard for Design Loads.;iv)

NBC 105: (Draft Nepal Seismic Design Standard)v)

IS : DOC : CED39 (5263) Guidelines for Ductile Detailing of Reinforced
Concrete Structure subjected to Seismic Forces (under printing).
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2

0.8

Zone A

Zone C

0.8

Zone B

0.9

1.0
1.0
0.8

Kathmandu

Zone B
Zone C

0.9

Zone A

Figure 1.1 : Seismic Zoning Map of Nepal for this MRT

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3
2

Interpretation
2.1

2.2

General
2.1.1

In this MRT, the word `shall' indicates a requirement that is to be adopted
in order to comply with the provision of this documents, while the word
`should' indicates recommended practice.

2.1.2

References to `Code' indicate the draft standard for Seismic Design of
Buildings in Nepal (NBC 105).

2.1.3

Words implying the singular only also include the plural and vice versa
where the context requires this.

Terminology
In this Standard, unless inconsistent with the context, the following definitions
shall apply :ADDITIONAL BARS means the longitudinal bars that shall be provided inaddition to regular bars at supports as top bars and at mid-span as bottom bars ofa beam.
CHAIR means an element made of steel bar which is used to maintain thevertical distances between top and bottom bars in slabs.
DEAD LOAD means the weight of all permanent components of a building
including walls, partitions, columns, floors, roofs, finishes and fixed plant andfittings that are an integral part of the structure.
DESIGN means use of rational computational or experimental methods inaccordance with the established principles of structural mechanics.
DIAPHRAGM means a member composed of a web (such as a floor or roofslab), or a truss which distributes forces to the horizontal load-resisting system.
DUCTILITY means the ability of the building or member to undergo repeated
and reversing inelastic deflection beyond the point of first yield while
maintaining a substantial proportion of its initial maximum load-carrying
capacity.
FRAME means a system composed of interconnected members functioning as acomplete self-contained unit with or without the aid of horizontal diaphragms or
floor-bracing systems.
HORIZONTAL LOAD-RESISTING SYSTEM means that part of thestructural system to which the horizontal loads prescribed by this Standard areassigned.

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IMPORTANT BUILDINGS means those buildings which either housefacilities essential before and after a disaster (eg., hospitals, fire and police
stations, communication centres, etc.), or which by their very purpose have tohouse large numbers of people at one time (eg., cinema halls, schools, convention
centres, etc.), or which have special national and international importance (eg.,palaces, etc.), or which house hazardous facilities (eg., toxic or explosive
facilities, etc.).
LANDSLIDE means the downward and outward movement of slope-forming
materials.
LIQUEFACTION means the phenomenon in which relatively loose, saturated
sandy soils lose a large proportion of their strength under seismic shaking.
LEVEL OF LOCAL RESTRAINT means the level at which the groundmotion of the earthquake is transmitted to the structure by interaction between thefoundation materials and the foundation elements by friction and bearing.
LIVE LOAD means the load assumed or known to result from the occupancy or
use of a building and includes the loads on floors, loads on roofs other than wind,loads on balustrades and loads from movable goods, machinery, and plant that are
not an integral part of the structure and may be changed during the life of thebuilding with a resultant change in floor or roof loading.
LUMPED MASS means the theoretical concentration of the mass of adjacent
upper and lower half storeys at any floor level.
MASONRY INFILL WALL means any structural wall constructed in brickwith cement sand mortar inside the frame and intended to carry horizontal loadby equivalent compression strut action.
NON-LOAD BEARING WALL means any wall which is not intended to carry
any significant external loads and which functions just as a cladding, partition
wall or filler wall.
ORDINARY BUILDING means any building which is not an importantbuilding (eg., residential, general commercial, ordinary offices, etc.).
REGULAR BARS means the bars that shall run continually parallel to the wallsof a beam to form a cage. The minimum number of regular bars in a beam is
four.
SHORT COLUMN means a column whose effective length is reduced due tothe sandwiching effect of a window sill wall spanning between two adjacentcolumns. The column effectively spans between lintel and sill level.
SOFT STOREY means a storey having a sudden decrease in its lateral stiffness
compared to the adjacent upper storey.
STOREY means the space between two adjacent floors or platforms.

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2.3

NBC201V2.RV7

SymbolsA

Maximum horizontal length of building

As

Area of steel bar

B

Maximum horizontal width of building

Cd

Design seismic coefficientD

Lateral stiffness of column

fckCharacteristic compressive strength of concrete

Fi

Horizontal seismic force applied at level ifyCharacteristic strength of steelhiHeight of the level i above the lateral restraint imposed by groundK1, K2

Plan length of structural wings

K

Steel grade Fe550 (high-strength, cold-worked)

Kc

Stiffness ratio of column (moment of inertial divided by its
length)lCentre-to-centre span of beam

M

Steel grade Fe250 (mild steel)RC

Reinforced cement concreteteThickness at the edge of the pad foundationtm

Maximum thickness of the pad foundation

T

Steel grade Fe415 (high-strength, cold-worked)

V

Total horizontal seismic base shear

Vij

Horizontal load carried by a column line j at level iWi

Proportion of the Wt at a particular level i

Wt

Total of the vertical dead loads and appropriate live loads above
the level of lateral restraint provided by the groundφ

Diameter of steel bar
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3

Selection and Investigation of Site
3.1

GeneralThis section sets out some of the requirements to be considered during site
selection for the construction of buildings in order to minimise the risks to thebuildings from primary geological as well as secondary seismic hazards such as
fault rupture, landslides and liquefaction. A building shall not be constructed if
the proposed site is :-3.2

Water-logged
A rock-falling area
A landslide-prone area
A subsidence and/or fill area
A river bed or swamp area

Use of Local Knowledge
It is a good practice during the construction of a building to examine the existing
local knowledge and the history of the performance of existing buildings. This
will assist in identifying whether there is any danger from inherent naturalsusceptibilities of the land to the processes of sliding, erosion, land subsidence
and liquefaction during the past earthquakes or any other natural/geologicalprocesses likely to threaten the integrity of the building. The local practice ofmanaging such hazards, if any, should be judged against the required level of
acceptable risk.

3.3

Site Investigation Requirements
Site exploration shall be carried out by digging test pits, two as a minimum, andmore if the subsurface soil condition shows a significant variation in soil type.
Generally, the minimum depth of exploration for a building covered by this MRT
shall be 2 m. In hilly areas, exploration up to the depth of sound bed-rock, if itlies shallower than 2 m, should suffice.
No exploration shall be required if the site is located on rock or on fluvial terraces(Tar) with boulder beds.
The soils encountered in the test pits should be classified as per Table 3.1.

3.4

Allowable Bearing Pressure
The allowable bearing pressure that can be used is given in Table 3.1 inconjunction with the visual classification of the subsurface soil type.

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TABLE 3.1 : FOUNDATION SOIL CLASSIFICATION AND SAFE BEARING
CAPACITY
Foundation
Type of Foundation Materials Classification

NBC201V2.RV7

Presumed Safe
Bearing
Capacity, kN/m2

1.

Rocks in different state ofweathering, boulder bed,
gravel, sandy gravel and sandgravel mixture, dense or loose
coarse to medium sandoffering high resistance topenetration when excavatedby tools, stiff to medium clay
which is readily indented witha thumb nail.

Hard

≥ 200

2.

Fine sand and silt (dry lumps
easily pulverised by thefinger), moist clay and sandclay mixture which can beindented with strong thumbpressure

Medium≥ 150 and
< 200

3.

Fine sand, loose and dry; soft
clay indented with moderate
thumb pressureSoft≥ 100 and
< 150

4.

Very soft clay which can bepenetrated several centimetreswith the thumb, wet clays

Weak≥ 50 and< 100

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4

The Building Structure
4.1

Description
The structure is a reinforced concrete frame without any contribution of masonry
infill walls in resisting the vertical or seismic loads. The frame shall comply with
Clause 4.1, 4.2 and be designed to resist earthquake forces as a bare frame.

4.2

Restrictions on the Structural Layout
For a structure to be built using this MRT, it shall comply with the restrictions set
out below. If the structure does not comply, it must be designed in accordancewith the Standards referred to in Clause 1.2 or latest appropriate standard.
The restrictions are :POSSIBLE SINGLE

h1

h2

h3
H

h4

STOREY PENTHOUSE

a5
a4
a3

b3
b
B 2

A

a2

b1

a1

CONDITIONS FOR DETAILED DIMENSIONS
A and B>
25.0 m
B/3 < A < 3 x B
axb>
13.5 sq. m.
a b
>
4.5 m
A or B >6 baysREINFORCED CONCRETE FRAME(a)

Neither A nor B shall exceed 6 bays in length nor 25 metres. Each bay
shall not exceed 4.5 m, as shown in Figure 4.1.

[Note: 1.
2.

NBC201V2.RV7

Openings can be provided as per functional/architecturalrequirements.
Foundation is not shown.]
Figure 4.1 : Reinforced Concrete Frame

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9(b)

A shall be not greater than 3 B nor less than B/3.

(c)

Neither H/A nor H/B shall exceed 3.

(d)

The area of a slab panel shall not be more than 13.5 square metres.

(e)

The maximum height of the structure is 11 m or 3 storeys, whichever isless, from the level of lateral restraint. Within an 11 m height, there may
be an additional storey of smaller plan area. The area of this shall not
exceed 25 % of the area of a typical floor, as given in Figure 4.1. If thislimit is exceeded, it shall be considered as an additional storey and not
permitted.

(f)

The length of wings on the structure shall be restricted such that K1 andK2 shall be less than the lesser of 0.25 A or 0.25 B. The width of thewings shall be restricted as shown in Figure 4.2. The plan shape of thebuilding excluding wings shall be rectangular.

(g)

All columns resisting lateral load shall be vertical and shall continue on
the same centreline down to foundation level. The top storey may,
however, be smaller or have a different geometry subject to the provisionsof subparagraph (e) above.

<K1/2

<K1/2

A or Bk1

k1

k1

A or B

A or B

k2

<K2/2

<K1/2

K1, K2 < 0.25 A or 0.258, which ever is less.
Figure 4.2 : Restrictions on Plan Projection

NBC201V2.RV7(h)

No walls except a parapet wall shall be built on a cantilevered slab. Suchwalls shall be constructed only if the cantilevered slab is framed withbeams.

(i)

The foundation shall be at a uniform level.

(j)

Buildings shall not have a soft storey.

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5Construction Materials
5.1

Concrete
The concrete to be used in footings, columns, beams and slabs, etc., shall have aminimum crushing strength of 15 N/mm² at 28 days for a 150 mm cube.
Cement: Cement shall be as fresh as possible. Any cement stored for more than
two months from the date of receipt from the factory should either be avoided ortested and used only if the test results are found to be satisfactory. Any cement
which has deteriorated or hardened shall not be used. All cement used shall be
Ordinary Portland Cement meeting the requirements of NS : 049-2041. It isadvisable to use cement which has obtained the NS mark if independent tests are
not carried out.
Coarse Aggregates: Coarse aggregates shall consist of crushed or broken stoneand shall be hard, strong, dense, durable, clean, of proper grading and free fromany coating likely to prevent the adhesion of mortar. The aggregate shall be
generally angular in shape. As far as possible, flaky, elongated pieces shall be
avoided. The aggregate shall conform to the requirements of IS : 383-1970 and IS: 515-1959.
The coarse aggregates shall be of following sizes :(a)Normal cement concrete with a thickness of 100 mm and above - gradedfrom 20 mm downwards(b)

Cement concrete from 40 mm to 100 mm thick - graded from 12 mm
downwards

Sand: Sand shall consist of a silicious material having hard strong, durable,
uncoated particles. It shall be free from undesirable amounts of dust lumps, softor flaky particles, shale, salts, organic matter, loam, mica or other deleterious
substances. In no case shall the total of all the undesirable substances exceed five
percent by weight.
[Note : Refer to the construction guidelines ]5.2

Brickwork
The brick masonry shall be built with the usually specified care regarding presoaking of bricks in water, level bedding of planes fully covered with mortar,
vertical joints broken from course to course and their filling with mortar fully.
Bricks : The bricks shall be of a standard rectangular shape, burnt red, handformed or machine-made, and of crushing strength not less than 3.5 N/mm². The
higher the density and the strength, the better they will be. The standard
brick size of 240 x 115 x 57 mm with 10 mm thick horizontal and vertical mortar
joints is preferable. Tolerances of -10 mm on length, -5 mm on width and ±3 mm
on thickness shall be acceptable for the purpose of thick walls in this MRT.

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Wall Thickness : A minimum thickness of one half-brick and a maximum
thickness of one brick shall be used.
Mortar : Cement-sand mixes of 1:6 and 1:4 shall be adopted for one-brick and ahalf-brick thick walls, respectively.
The addition to the mortars of small
quantities of freshly hydrated lime in a ratio of ¼ to ½ of the cement will greatly
increase their plasticity without reducing their strength. Hence, the addition oflime within these limits is encouraged.
Plaster : All plasters should have a cement-sand mix not leaner than 1:6. They
shall have a minimum 28 days cube crushing strength of 3 N/mm².
5.3

Reinforcing Steel Bars
Reinforcing steel shall be clean and free of loose mill-scale, dust, loose rust andcoats of paints, oil, grease or other coatings, which may impair or reduce bond. It
shall conform to the following NS or IS specifications.
Mild steel bars conforming to NS:84-2042 or IS: 432 (Part I) - 1996 with fy = 250
N/mm², or high-strength deformed bars conforming to IS : 1139-1966 or NS:191-2046 with fy = 415 N/mm² or fy=550 N/mm² shall be used for reinforcing all
masonry and concrete.

6[Note: 1.

In the presentation of this MRT, fy = 415 N/mm² steel is assumed formain bars in beams and columns. For using any other steel with lower
values of fy, the steel area shall be correspondingly increased.

2.

High-strength steel bars having fy= 550 N/mm² may only be used asreinforcement in slabs.

3.

7 φ bars steel grade Fe550 can be replaced by 8 φ bars of steel grade
Fe415. Similarly, 5 φ bars of steel grade Fe550 can be replaced by 6 φbars of steel grade Fe250.

Design Procedure
6.1

Procedure Outline
The simplified design procedure comprises the following stages:

NBC201V2.RV7(a)Conforming that the building plan meets the structural layout restrictions(Clause 4.1, 4.2).

(b)Calculate total horizontal seismic base shear on the building (Clause ?).

(c)Distribute total horizontal seismic base shear up the height of the building(Clause 6.3).

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12

6.2

(d)

Distribute the total horizontal seismic load to the individual load resistingelements (Clause 6.4).

(e)Design and detail the structural elements :i)

The frame(Clauses 7.1 – 7.3)

ii)

Recommendation for minimum
sizes and reinforcement(Clause 7.3.2)(f)

Reinforcing non load-bearing walls(Section 8)(g)

Reinforcing of parapets(Section 9)

Total Horizontal Seismic Base Shear
The structure shall be designed to withstand a total horizontal seismic base shear,V, calculated in accordance with the formula :V = Cd x Wt

(6.1)

where,
Wt

is the combination of the total vertical dead load and 25 % of the live
loads above the level of lateral restraint provided by the ground.

6.2.1

Design Seismic Coefficient1
The design seismic coefficients, Cd, for the design of frames without
masonry in-fills in the zones shown in Figure 1.1 are :Zone A = 0.080, Zone B = 0.072, Zone C = 0.064
Where a building location lies close to a zone boundary so that its
particular zone is uncertain, then the building shall be assumed to fall inthe zone requiring the higher value of basic seismic coefficient.

1

Seismic coefficients are in accordance with NBC 105 for ductile frames of normal
importance on a medium grade of soil.

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6.3

Distributing Total Horizontal Seismic Base Shear
The total horizontal base shear, V, shall be distributed up the height of thebuilding in accordance with the formula (refer to Figure 6.1) : Wt hi Ft = V  ∑ Wt hi 
 i


(6-2)

where,
Fi

is the load applied at the level designated as i.

Wi

is the proportion of Wt at ith level.

hi

is the height of level i above of level of lateral restraint imposed by theground.

F4i th FLOOR

F3

h1

F2
F1

Figure 6.1 : Floor Level Lateral Forces

6.4

Distribution of the Seismic Shear to the Individual Frames
In a particular storey i, the shear force, Vij, resisted by a column line j shall be
determined from the formula :NBC201V2.RV7

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14

 Dij  Roof
Fij = Fi ∑ Dij  ∑
i
 j


(6-3)

where :
Roof :

ΣFi
i
Dij

ΣDij

is the sum of floor loads above the particular storey i.
is the effective lateral stiffness of the particular column line j instorey i.
is the sum of the effective lateral stiffness of all the columns inparticular storey i.

Lateral stiffness of an individual column is given by :

 EI 
D = 12  3e 
 h 

(6-4)

where :

7

E

Young's modulus of column concrete.

Ic

Moment of inertia of column in the plane of consideration.

hHeight of the column

Design of the Frames
7.1

FramesAll frames shall be designed :NBC201V2.RV7(a)to support the applied vertical gravity loads (including the weight of thewalls) without assistance from the walls, and(b)for seismic condition using forces as per Clause 6.1.

31 October 1994

15
7.2

Frame Analysis
Frame-by-frame analysis may be carried out using any of the hand calculation
methods (eg, Portal method, Sutherland-Bowman method, Arya's Modified
Frame method, or Muto's D-value method), or by using a computer analysis, todetermine the forces and moments in frame members.

7.3

Frame Design
The members and joints shall then be designed in accordance with standardpractice and shall be detailed to achieve ductile deformations under severe
earthquakes.
The recommendations for member sizes and minimum reinforcement in allcomponents are shown in Figures 7.1 to 7.4. The reinforcement shall also
comply with the applicable sections.
7.3.1

Basis of Recommendations
The recommended sizes of members and the reinforcement are based on
sample calculations using the following data :Building Occupancy:

Residential

Column Plan:

4.5 x 3.0 m bays

Number of Storeys

:

three

Storey Height
1st storey:
Upper storey :NBC201V2.RV7

3.2 m floor to floor
2.8 m floor to floor

Wall Thicknesses:

up to 115 mm thick brick wallor equivalent for all internal
walls and up to 230 mm thick
brick wall or equivalent for all
external walls

Cantilever Floor Projection:

1.0 m (from centre-line ofbeam)

Concrete mix:

M15 (15 N/mm² cube
crushing strength at 28 days)
minimum

Reinforcement

:

Fe250
(minimumyield
strength = 250 N/mm²),
Fe415(minimumyield
strength = 415 N/mm²),
Fe550(minimumyield
strength = 550 N/mm²)

31 October 1994

16

7.3.2

Mortar:

Minimum 1:4 cement-sandmortar for half-brick thickwall and 1:6 cement-sandmortar for one-brick thick

Bricks:Minimum crushing strength
3.5 N/mm²

Seismic Coefficient:

Cd = 0.08 (for infill frame on
medium grade of soil)

Recommended Members Sizes and Minimum Reinforcement
Slab
Roof and Floors
Thickness
Steel

:
:

100 mm
T08 or K07 and M06 or K4.75 bars as shown in
Figure 7.1.

Beams
Roof and floors (both directions)
Width
Depth

: 230 or 240 mm: 325 mm overall including slab

Plinth beam (both directions)
Width
depth

: 230 mm or 240 mm: 200 mm overall

Longitudinal SteelThe top and bottom steel reinforcement bars are given in Table 7.1 fordifferent spans. The placing of steel shall meet the requirements specified
in Figure 7.2.

NBC201V2.RV7

31 October 1994

17600
S E E B E A M D E T A IL
K 4 .7 5 -1 5 0
a4

a5

b3

100

a3

275

a2

325

a1

25

A

S E E B E A M D E T A IL
K 0 7 -1 5 025

K 0 7 -1 5 0

180

25

K07-150

K07-150

b2

E D G E S L A B D E T A IL - A
0 .2 5 b

0 .2 5 b
S E E B E A M D E T A IL
K 4 .7 5 -1 5 0

1 5 m m th .C L E A R C O V E R

100

T 1 0 -1 5 0

100

100

b1

K 0 7 -1 5 0

0 .2 5 b

k 4 .7 5 -1 5 0

K 0 7 -1 5 0
150

0 .2 5 b

0 .2 5 bA

K 0 7 -1 5 0

25

C H A IR180

BO TTOM BAR

25

LEG END
K

230

07

150

D E T A IL A T - B

C /C s p a c in g
D ia m e te r o f B a r s
T y p e o f s te e l

C H A IR D E T A IL
0 .2 5 b

0 .2 5 b

0 .2 5 b

k 4 .7 5 - 1 5 0

K 0 7 -1 5 0

a1

TOP BAR25

NO TE:
1 . K 0 7 b a rs c a n b e re p la c e d b y T 0 8 & k 4 .7 5 c a n b e re p la c e d b y M 0 6 b a rs .
2 . T o p b a rs c o u ld b e c u rta ile d a t 0 .2 5 o f s h o rt s p a n fro m e d g e o f s u p p o rt.
3 . C u t fo r s ta ir w e ll c a n b e m a d e a n y w h e re a s d e s ire d w ith s la b e d g e d e ta il a s
in d e ta il A .
4 . N o w a ll o t h e r th a n p a r a p e t s h a ll b e b u ilt o n c a n tile v e r s la b .
5 . 1 5 m m c le a r c o v e r s h a ll b e m a in ta in e d f o r b a rs .
6 . T h e b a rs e x te r n d in g th ro u g h a d ja c e n t a p a n s to a n y s p a n le s s th a n 2 m s h a ll
n o t b e c u rta ile d .
7 . E x p o s e d s u rfa c e s o f c o n c re te s h a ll b e k e p t c o n d tin u o u s ly w e t o r d a m p a t
le a s t fo r o n e w e e k .
8 . I n n o rm a l c ir c u m s ta n c e s , fo r m w o rk c a n b e re m o v e d o n ly a fte r tw o w e e k s o f
c o n c r e tin g .

0 .1 5 b

S E E B E A M D E T A IL

200

SLAB PLAN

0 .1 5 b

0 .2 5 b

0 .2 5 b
K 0 7 -1 5 0

a2

a3

K 0 7 -1 5 0
150

B

25

B

K 0 7 -1 5 0

a4

a5

S E C T IO N A T X - X
900

0 .2 5 b

0 .2 5 b

K 0 7 -1 5 0

K 0 7 -1 5 0
b1

0 .1 5 b
k 4 .7 5 -1 5 0

K 0 7 -1 5 0

b2

S E C T IO N A T Y - Y

Figure 7.1 : Slab Reinforcement Details
NBC205V2.RV7

0 .2 5 b

0 .2 5 b

T 1 0 -1 5 0

31 October 1994b3

18
TABLE 7.1 : LONGITUDINAL STEEL IN BEAMS
Span

4.5 ≥ l > 4.0

Bar Regular
type/
Level

4.0 ≥ l > 3.5

Additional

Additional

Regular

Additional

Top

Top

Top Bot.

Top

Bot.

Roof 2T12 2T12 1T12 1T12 2T12 2T12 1T12 1T10 2T12 2T12 1T10 1T10 2T12 2T12

1T10

-

II

2T16 2T16 1T16 1T12 2T16 2T16 1T12 1T10 2T12 2T12 2T12 1T16 2T12 2T12

1T16 1T12

I

2T16 2T16 3T12 1T16 2T16 2T16 2T12 1T16 2T16 2T16 1T16 1T16 2T16 2T16

1T12 1T12

Bot.

Plinth 2T12 2T12 --[Note:

Additionall < 3.0

RegularTop Bot. Top

Regular3.5 ≥ l > 3.0

Top Bot. Top

2T12 2T12 1.
2.
3.

Bot.

-

Bot.

2T12 2T12

Bot.

-

-

2T12 T212--

1T12 stands for 1 number of 12 mm diameter of steel grade Fe415 bar.
Additional top bars coming from adjacent span shall not be curtailed if the
span under question is less than 2 m.
In case of two adjacent beams of different span, top bars for longer spanshall govern.

Transverse Stirrups : The transverse stirrups are calculated and presented inTable 7.2 for different spans. The placing of transverse stirrups shall meet therequirements set out in Figure 7.2. The depth of the foundation shall not be lessthan 1.2 m.
TABLE 7.2 : TRANSVERSE STIRRUPS IN BEAMS(All stirrups are 2-legged)
Level\Span4.5 ≥ l > 3.5

3.5 ≥ l > 3.0

Remarks
In theRemaining
Length of All
Beams Use
M06 @ 150

Roof

End 600 mm M06 @ 100

End 600 mm - M06 @ 100

II

End 900 mm M06 @ 100

End 600 mm - M06 @ 100

I

End 0.3 l M06 @ 80

End 0.3 l - M06 @ 100

PlinthM06 @ 100

M06 @ 100

[Note:

1.

M06 @ 100 stands for 6 mm φ Fe250 (mild steel) two-legged stirrups at a spacing of
100 mm c/c.]

Columns
Size and Longitudinal SteelGross sections of column and longitudinal steel are calculated and presented inTable 7.3.

NBC205V2.RV7

31 October 1994

19
2 30

Z ONE OF TO P B A R
O V E R LA P P ING

Z ONE OF B O TT O M B A R
O V E R LA P P ING

6 00

M IDD LE 1/3 OF S P A N

0 .3 L

0 .3 L2 T 12

2 T 12

1 T 12

1 T 12

1 T 12M 0 6 (2 L )-100

M 0 6 (2 L )-150

M 0 6 (2 L )-100

M 0 6 (2 L )-100

6 00

6 00

M 0 6 (2 L )-150

2 T 1 2(RE GU LA R TO P B A R)

M 0 6 (2 L )-100

300

100

325

0 .3 L

0 .3 L2 T 12

2 T 12

1 T 12

1 T 12

2475

6 00

6 00

6 00

2 T 122 30 X 230

2 30 X 230

1 T 12(A D DI T I ON A L
T OP B A R)

2 30 X 230

700

M 0 6 (2 L)-1 00
2 T 16

L A P P ING OF T O P B A RS

2 T 162 T 162 T 101 T 101 T 12325

M 0 6 (2 L )-100

M 0 6 (2 L )-150

M 0 6 (2 L )-100

M 0 6 (2 L )-100

M 0 6 (2 L )-150

M 0 6 (2 L )-100
25

1 80

25

2 30
1 T 106 00
L A P P ING OF B O T T O M B A RS

6 00

2 T 12

6 00

6 00

6 00

6 00

6 00
2 T 162 T 162 T 162475

1 T 100 .3 L

0 .3 L2 T 12
1 T 12

L A P LE N GTH

325

M 0 6 (2 L )-100

6 00

M 0 6 (2 L )-150

L A P LE N GT H

2 30 X 230
0 .3 L2 T 162 T 162 T 12

2 T 12

2 T 12 + 1 T 12

0 .3 L2 T 161 T 12M 0 6 (2 L )-100

1 T 10D E T A IL A T 1

2 30 X 230

100

700

2 30 X 230

2 T 12(RE GU LA R
B OT TO M B A R)

6 00

6 00

6 00

6 00

2 T 12

2 T 166 00

M 0 6 (2 L)-1 00

6 00

2 T 162 30 X 230

2 30 X 230

2875

2 30 X 230

2 T 12230

2 T 12220

M 0 6 (2 L )-150

25

M 0 6 (2 L )-150

2 T 12

2 T 12

2 T 12

2 T 12

2 T 162 T 16 + 2 T 10

25

25

100

25
100

2 T 12275

M 0 6 (2 L)-1 00
180

T W O LE GS
230

275

M 0 6 (2 L)-1 00

25

25

25

M 0 6 (2 L)-1 00

1 80

D ET A IL A T 3

25

2 T 16 + 1 T 10

25

1 80
2 30

D E T A IL A T 4

25

2 T 16 + 2 T 10

25

1 80

25

2 T 12

S T IR R U P DE TA IL

2 30

D E T A IL A T 5

N ote:
1 . L a p p in g o f th e b o tto m b a r s h o u ld b e re s tricted to a region at least 500 m ma w a y fr o m th e c o lu m n fa c e b u t e x c lu d in g the m iddle quater length of thebeam .
2 . L a p p in g o f th e to b a r s h o u ld be done only in m iddle 13 le n g th o f beam .
3 . N o t m o re than 50 % o f th e b a rs s h o u ld b e s p liced at one section.
4 . M a in b a rs s h a ll n o t b e c u rta ile d in the beam s fram ing infill w alls.
5 . If a lo n g e r a n d s m a lle r s p a n s e x it a d ja c e nt, top bars of longer spab shallg o vern.
6 . C o n c re te g ra d e M 1 5 s tands for concrete m ix
1 :2 :4 (C e m e n t:S and:A ggregate).
7 . L a p p in g o f b a rs s h a ll not be less than 56 Ø .
8 . C u rta il a d d itio n a l to p b a rs 0 .2 5 L a w a y from support and additional bottomb a rs 0 .1 5 L a w a y fro m s u p port in free span beam s.
9 . T h e b a rs e x te n d in g th ro u g h a d ja c e n t s pans to any span w hich is less than
2 .0 m s h a ll n o t b e c u rta ile d a n d s tirru p s be provided sam e as the ends ofa d ja c ent beam .
1 0 . B e a m s s p a n n in g a lo n g s tru c tu ra l in fill w a lll shall be casted only after erectiono f th e w a ll.
1 1 . T h e e x p o s e d s u rfa c e s o f c o n c re te s h a ll be kept continuously w et or dam p
fo r a tle a s t one w eak.
1 2 . In n o rm a l c irc u m s ta n c e s fo rm w o rk can be rem oved after three w eakso f c o n creting.
1 3 . C o lu m n b a r not show n.

Figure 7.2 : Beam Details
NBC205V2.RV7

D E T A IL A T 2

2 T 12

2 T 12 (LA P P E D)

2 30

2 T 12 + 1 T 12

4 500 > > 4000

75

25

25

2 30

2 T 124 500 > > 4000

1 80

31 October 1994

INDEX:K 05 (2L) – 100
C/C spacing
No. of Leg
Diameter of bar
Type of steel
2

T

I2
Diameter of bar
Type of steel
No. of bar

F ig u re 7 .3a : B ea m D e ta il(T w o W a lls e a c h W ay/ 100 sq.m .)20
TABLE 7.3 : COLUMN SIZES AND LONGITUDINAL STEEL
Corner Column

Face Column

Interior Column

Size

Reinf.
(As)

Size

Reinf.
(As)

Size

Reinf.
(As)III*

230 x 230

4T16

230 x 2304T12

230 x 230

4T12

II

230 x 230

4T16

230 x 230

4T16

230 x 230

8T12I

270 x 2704T16

270 x 2704T16

270 x 270

8T12Storey* and Penthouse.

[Note: 1.

4T16 stands for 4 number of 16 mm φ Fe415 steel bars].

Transverse Stirrups
The transverse stirrup ties in all columns shall be :Ends of columns for 600 mm length
Remaining height- T 08 @ 100- T 06 @ 125[Note: 1.

Continue the column stirrups as specified to the ends if column stands
adjacent to a window or such opening to take care of the short-column
effect.]2.

T08 @ 100 stands for 8 mm φ steel grade Fe415 stirrups at the spacing of
100 mm c/c. All stirrups are of a closed type.]

Details of columns shall be as specified in Figure 7.3.
Pad Foundations
Sizes and reinforcement in pad foundations for different soil types and loadings arepresented in Tables 7.4a to 7.4d. All foundations are individual tapering-type pads.
Details of foundations shall be as given in Figure 7.4.

NBC205V2.RV7

31 October 1994

5 00

M 06 (CT)-125

M 06 (CT)-125

5 00

600

M 06 (CT)-100

5 00

600

M 06 (CT)-100

600

T 08 (CT)-100
M 06 (CT)-125

OVER LAPPING AT MIDDLE 1 2 OF COLUMN HT.

5 00

A

700 or 56 Ø

M 0 6 (CT)-125

M 06 (CT)-125

WHICHEVER IS GREATER

T 08 (CT)-100

T 08 (CT)-100

450

600
600

T 08 (CT)-100
M 06 (CT)-125

OVER LAPPING AT MIDDLE 1 2 OF COLUMN HT.

4 T 16
8 T 12I S O M E T R I C O F C O LU M N / B E A M
J O I N T R E I N F O R C E M E N T D E TA IL

8 T 12

3 T1 2

2 70
40

1 80

40

180

270

M 0 6 -1 2 5

8 T 12

8 T 12S E C T IO N - 1

S E C T IO N - 2

S E C T IO N - 375

75

2 70 X 270

600

I NDE X

T 08 (CT)-100

T 08 (CT)-100

K

600

230

M 0 6 -1 2 540500

2 70 X 270

05(C T )

2 T1 2

C lo se d st irru p s
D ia m e te r o f b a r

totm

T 08 (CT)-125

C L O S E D S T I R R U P S (C T ) D E T A IL

S E C T IO N

1 00

C /C sp a cin g

75

T H R O U G H IN T E R IO R FR A M E

T yp e s o f ste e l
2

N OT E:
1.
B a r s s h o u l d b e l a p p e d i n m i d d l e half of the c olum n.
2.
P r o v i d e s ti r r u p s i n b e a m - c o l um n joints as s pec ified.
3.
N o t m o r e th a n 50 % o f th e b a r s s h o u l d b e s p l i c e d at one s ec tion.
4.
C o n c r e te g r a d e m 1 5 s ta n d s fo r c o n c r e te m i x 1 :2 :4 (c em ent:s and:aggregate).
5.
B e a m b a r b o t s how n.

L X BFigure 7.3 : Column Detail
NBC205V2.RV7

4 T 12( L A P P E D)

M 0 6 -1 2 5
2 T1 2T 0 8 (CT)-125

T 08 (CT)-125

T 0 8 (CT)-125

4 T 16

3 T1 22 70 X 270
4 T 16

T 08 (CT)-100

ZONE OF MAIN BAROVER LAPPING AT MIDDLE 12 OF COLUMN HT.

600

40

T 08 (CT)-100

T 08 (CT)-100600

B A R O V E R L A P P I N G D E TA IL - A

T 08 (CT)-100

325

ZONE OF MAIN BAR

5 00

4 T 12

325

ZONE OF MAIN BAR

325

21

31 October 1994

T

12

D ia m e te r o f b a r
T yp e s o f ste e l
N o. o f bar

22

100

100

t e'

50 75

t m'

500

LxB

SEE TEXT
Dimensions are given in the text

Figure 7.4 : Pad Foundations

TABLE 7.4A : PAD FOUNDATION SIZE FOR WEAK SOILS(safe bearing capacity = 50 kN/m²)

ColumnType

ColumnLocation
Cantilever
Side

FoundationPlan
L x B (m)Thickness
at edgeste (mm)Maximum
thickness
tm (mm)Reinforcement
each wayAs

CornerNo

1.6 x 1.6

150

300

6 T 10CornerYes

1.7 x 1.7

150

300

7 T 10FaceNo

1.9 x 1.9

150

375

7 T 12Face

Yes

2.2 x 2.2

150

400

8 T 12

Interior-

2.6 x 2.6

200

500

10 T 12[Note : 1.

NBC205V2.RV7

6T10 Stands for six 10 mm diameter Fe415 bars.]

31 October 1994

23
TABLE 7.4B : PAD FOUNDATION SIZE FOR SOFT SOILS(safe bearing capacity = 100 kN/m²)
ColumnType

ColumnLocation
Cantilever
Side

FoundationPlan
L x B (m)Thicknessat Edgeste (mm)Maximum
Thickness
tm (mm)Reinf.
Each WayAs

CornerNo

1.1 x 1.1

150

325

5T10

CornerYes

1.2 x 1.2

150

325

6T10

Face

No

1.4 x 1.4

150

400

6T12

Face

-

1.6 x 1.6

150

425

7T12

Face

Yes

1.6 x 1.6

150

425

7T12

Interior-

1.8 x 1.8

200

500

9T12

TABLE 7.4C : PAD FOUNDATION SIZE FOR MEDIUM SOILS(Safe Bearing Capacity = 150 kN/m²)

Cantilever SideFoundation
Plan
LxB
(m)

Thickness at
Edge
te
(mm)

Maximum
Thicknesstm(mm)

Reinforcement
Each WayAs

Cornerno1.0 x 1.0

150

325

5T10

Corneryes

1.0 x 1.0

150

325

6T10

Face

no

1.2 x 1.2

175

425

8T10

Face

yes

1.3 x 1.3

175

450

7T12

Interior-

1.6 x 1.6

225

525

8T12

ColumnType

NBC205V2.RV7

ColumnLocation

31 October 1994

24
TABLE 7.4D : PAD FOUNDATION SIZE FOR HARD SOILS(safe bearing capacity = 200 kN/m²)
ColumnType

ColumnLocation
Cantilever
Side

FoundationPlan
L x B (m)Thicknessat Edgeste (mm)Maximum
Thickness
tm (mm)Reinf. eachway
As

CornerNo

0.8 x 0.8

150

350

5T10

CornerYes

0.9 x 0.9

150

350

5T10

Face

No

1.0 x 1.0

200

450

7T10

Face

-

1.1 x 1.1

200

450

7T10

Face

Yes

1.1 x 1.1

200

450

7T10

Interior-

1.3 x 1.3

250

550

7T12

All plinth beams shall be constructed on a toe wall below them asgiven in Figure 7.5.

200

Toe Wall :250

4 T 12

150

45

GROUND LEVEL

55

230

55

55

55

150

55

450

Figure 7.5 : Toe Wall Details

NBC205V2.RV7

31 October 1994

25
8

Reinforcing Non-load Bearing Walls
8.1

Between Framing Columns
8.1.1

Solid Walls
To prevent walls from falling out, these shall be provided withhorizontal reinforced concrete (RC) bands through the wall at about
one-third and two-thirds of their height above the floor in each storey.
The width of the band should be equal to the wall thickness and its
thickness equal to that of the masonry unit, or 75 mm, whichever islarger. Reinforcement details shall be as given in Figure 8.1.
Reinforcement :

8.1.2

(a)

Longitudinal - two bars 8 mm φ (Fe415) anchoredfully in the RC column abutting the wall.

(b)

Transverse - links 6 mm φ (Fe250) stirrups at every
150 mm.

Walls with Openings
Provide an horizontal RC band through the wall at the lintel level ofdoors and windows and at window sill level in each storey as given in
Clause 8.1.1.
Details of the arrangement are given in Figure 8.2.

8.2

Outside Framing Columns
A horizontal RC band shall be provided through all walls - one at window-silllevel and the other at lintel-level. All details shall be the same as in Clause ?.
The reinforcement of bands shall be taken through the cross-walls into the RCcolumns as detailed in Figure 8.3.

NBC205V2.RV7

31 October 1994

26
t

l/3b

l/3b

l/3b

l/3h

INFILL - WALL

2.8 m < h < 3.2 m

l/3h

450

l/3h

A

B

A

3 m > b > 4.5 m

ELEVATION

Brick in 1:6 c/s mortar

COLUMN

BEAM

500

500

100

SECTION AT A - A

t100

SECTIONAL PLAN AT B - Bt

M

M 06 (I-L)-150

06

(1L)

60
1

DETAIL AT A

150
C/C spacing
No. of legs
Diameter of Bars
Type of steel

75

60

INDEX

T

2 T 0808
Diameter of bar
Type of steel
No. of bar

Figure 8.1 : Tie-Band Detail of Solid Walls

NBC205V2.RV7

31 October 1994

27t
3 m < b < 4.5 m

<300

A

2.8 m < h < 3.2 m

Tie BeamBA

0.3628BA

ELEVATION

COLUMN
500

500

100

SECTION AT A - A

t

100

BEAM

SECTIONAL PLAN AT B - Bt

M

M 06 (I-L)-150

06

(1L)

1

DETAIL AT A

150
C/C spacing
No. of legs
Diameter of Bars
Type of steel

60

75

60

INDEX

T

08

2 T 08

Diameter of bar
Type of steel
No. of bar

Figure 8.2 : Tie Up and Detail of Non-Structural Wall
NBC205V2.RV7

31 October 1994

28

t

LINTEL BAND

60

75

60

M 06 (I-L)-150
B

B

2 T 08

X- SECTION OF TIE BEAM
325

SILL BANDELEVATION
COLUMNt

WALL ABUTTING COLUMNDETAIL AT A
t
500

WALL OUTSIDE COLUMN LINE

INSIDE

500

300
OUTSIDESECTION AT B - B

t

500

t

300

500

300

DETAIL AT CDETAIL AT B

Figure 8.3 : Wall Outside the Frame
NBC205V2.RV7

31 October 1994

29
9

Parapets
9.1

GeneralParapets above roofs and at the edges of the balconies should not be taller than
one metre. They should either be constructed in reinforced concrete or be
reinforced with vertical RC elements spaced not more than 1.5 m apart. The
section of the vertical RC post may be kept to b x 75 mm, where b is the
thickness of the parapet. Such RC elements should be reinforced with twovertical bars of 8 mm diameter steel (grade Fe415) with transverse links 6 mm
φ diameter steel (grade Fe250) @ 150 mm centres. The vertical reinforcement
shall be tied in the steel of the slab or beam below with a minimum
embedment of 300 mm. Also, a handrail should be provided at the top with asection size and reinforcing as explained in Clause 8.1.1. For details, refer toFigure 9.1.

300

HAND RAIL

A

300
300

50
50

Wall thickness

2 T 08M 06 (I-L)-15075

SECTION AT A - A
Figure 9.1 :NBC205V2.RV7

Parapet Wall Tie-Up Details

31 October 1994

30
9.2

Flower Pots
Flower pots should not normally be placed on parapets. However, if it isdesired that they be placed there, they shall be adequately wired and held tothe parapet through pre-fixed steel hooks/anchors so that they will not be
dislodged in severe earthquake shaking.

NBC205V2.RV7

31 October 1994