京 都 大 学 防 災 研 究 所 年 報 第47号 C 平成16年3月
Annuals of Disas. Prev. Res. Inst., Kyoto Univ., No. 47 C, 2004

Test on Collapse Behavior of 3D Full-Scale Steel Moment Frames
Subjected to Cyclic Loading

Dawei LIU*, Tomohiro MATSUMIYA**,
Masayoshi NAKASHIMA,
Keiichiro SUITA* COE Researcher, DPRI, Kyoto University** Graduate Student, Graduate School of Engineering, Kyoto University

Synopsis
This paper reports on a full-scale test on a three-story, two-span by one-span steel
moment frame to characterize the cyclic behavior beyond the deformation ranges
considered in the contemporary seismic design. The following observations are noted:
Balanced deformations between members were observed in contemporary deformation.
In the larger deformation, pinching behavior was notable because of cyclic yielding atcolumn bases, and composite action between steel beams and RC slabs decreased. The
final failure occurred by first-story collapse mechanism promoted by severe
deterioration of column bases. The effect of ALC panels on the structural behavior was
nearly null.
Keywords: steel moment frame; full-scale test; seismic design; composite action; ALC
panels; column basedamage, and safety limit states, examinations into theinteraction of various nonstructural components andbuilding contents with building performance, among
many others. To verify individual research findings
and assure the expected performance of innovative
developments and practices, real data obtained from“observations” and “experiments” are essential.
They are rather difficult to acquire, however. A
large earthquake event occurs very scarcely, whichmakes it difficult to monitor or measure the real
behavior of structures at such an event. Interaction
between member and system behavior is known to becomplex; hence tests on a structural system that has

1. Introduction“Performance-based engineering” has become astandard norm for research, development, andpractice of earthquake engineering particularly after
the 1994 U.S. Northridge and 1995 Hyogoken-Nanbu(Kobe)
earthquakes(Performance,
1995;
Recommended, 2000; NEHRP, 2000; Notification,
2000; Midorikawa et al., 2003). Relevant themesof challenges range from the characterization ofstrong motions and their effects on the structural
response, quantification of multiple levels of
performance associated with the functionality,1considered in the present Japanese seismic design.
A beam fracture, its effect on the overall behavior,and the final failure mode were also noted. Third,
composite action between the steel beam and RC
floor slab and effects of exterior finishes (cladding)on structural behavior are discussed.

much redundancy are indispensable.
Building
structures, however, are massive, and it is difficult tofabricate and load them in the laboratory, whereas
miniature models are known to fail to duplicate theprototype behavior because of lack of similitude.
Considering these circumstances, the writers
conducted an experimental project in which a fullscale, three-story steel building frame was loaded
quasi-statically to failure. The primary objectives ofthe project were: (1) to acquire realistic data about
performance, progress of damage, and final failure of
the concerned frame in deformation ranges that are
far beyond those considered in contemporary seismic
design; (2) to examine the interaction between thelocal damage induced into individual members andelements and the global damage sustained by the
structural frame; (3) to observe effects of RC floorslabs on the behavior of steel moment frames; and (4)to examine the interaction between the structural
system and exterior finishes. This paper reports on
the outline and preliminary results of this project inthat the test was completed a few weeks before thetime of this writing. First, the paper introduces thetest structure and the adopted loading and measuring
procedures. Second, the overall behavior of the test
structure is outlined up to the deformation ranges
approximately two to four times as large as those

Reaction wall

3

C1

3

2

C1

2C1

C1

1C1

3

3

C1

G2

Link

3

C2

G1

3

C1

G1

3
2C2

2

C1

C1

9,250

C1

3

1,500

C1

CG1
2

Oil jack

North

3,500

3

The test structure was a three-story, two-bay by
one-bay steel moment frame as shown in Fig.1,
having a plan dimension of 12 m (in the longitudinal
direction) by 8.25 m (in the transverse direction).
The structure was designed following the mostcommon design considerations exercised in Japan forpost-Kobe steel moment frames. That is, the columns
were made of cold-formed square-tubes, beams weremade of hot-rolled wide-flanges, the throughdiaphragm connection details were adopted, in which
short brackets were shop-welded to the columns[Fig.2(a)]. The columns with short brackets weretransported to the test site, and they were connectedhorizontally to beams by high-strength bolts. Metal
deck sheets were placed on top of beams, with studs
welded to the beam top flanges through the metal
deck sheets. Wire-meshes were placed above themetal deck sheets, and concrete was placed on site.

3,500

South
ALC Panel

2. Test Structure

2

CG1

2
1

G2

2

C1

1

G1

G1

2
1C2

1

750

Steel block

2,850

1,500

North

2

8,250

6,000

3,975

6,000

Member
C2

G

2

2

2

G2
B2

6,000

6,000
3,975

12,000

1,500

CG1

2

2

CG1

C1

G1

2

B2

2

a

B3

2

Column
8,250

a

C2

G1

2

B3

CG1

a

2

South

B1

G2
2

2

Reaction wall

a

2C1

2

1

B1

G2

1

C1

G

2

C1

Beam

Section

1C1□‐300×9

1C2□‐300×122C1□‐300×92C2□‐300×93C1□‐300×12

3C2□‐300×16

B1

H‐400×200×8×13

B2

H‐300×150×6.5×9

2G1

H‐400×200×9×16

2G2

H‐400×200×9×16

3G1

H‐400×200×9×16

3G2

H‐400×200×9×16

2CG1

H‐400×200×8×13

3CG1

H‐400×200×8×13

B3

H‐200×100×5.5×8a

H‐200×100×5.5×8

Figure 1: Plan and Elevation of Test Structure (unit: mm)2

Column
Base plate

ColumnMortarAnchor bolt

RC slabPanel zone

Diaphragm

Bracket(a) Column Base Connection

Beam(b) Beam-to-Column Connection
Figure 2: Connection Details
Table 1: Material Properties of Steel and Concrete Used
S am pled P lates

Y eild s trengthUltim ate s trength(M P a)Colum n

B eam

(M P a)□ 300× 9,B CR295

386

456

□ 300× 12,B CR295

393

459

□ 300× 16,B CR295

399

451

flange, S N400B

287

434

347

455

Diaphragm P L-22, S N490C

web, S N400B

347

507

B as e plate P L-50, S N490B

315

461

M 33, S NR490B

350

514

M 36, S NR490B

341

A nc or bolt

Figure3: Overview of Test Structure(with ALC Panel)Conc rete

513
32.3

B eam : H ‐ 400× 200× 9× 16

plane, while the column rotations at the top werepermitted by the out-of-plane flexibility of the gusset
plates. Two quasi-static jacks, one in eachlongitudinal plane, were placed in this level, as shownin Fig.1.
Another feature of the test structure was theexterior finishes (cladding) installed during the test.
ALC (autoclaved lightweight concrete) panels wereplaced on one edge of the floor to examine the effects
of nonstructural elements on the hysteretic behaviorof the test structure. The ALC panels were installed
along the floor edge of the “South” plane (the one
with the overhang) as shown in Fig.3.Material
properties of the steel and concrete used for the test
structure were obtained by tensile coupon andconcrete cylinder tests. The properties thus obtained
are listed in Table 1.

In the design of the test structure, yielding and plastic
deformations were assigned for beam-ends, panelzones, and column bases; hence the column-to-beamstrength ratios ranged from 1.9 to 2.2. Fabrication andconstruction procedures adopted for the test structure
faithfully followed those exercised in real practice(Nakashima et al., 1998). Exception was the columnbases. Instead of embedding anchor bolts in thefoundation RC beams, anchor bolts were fastened in
short, deep steel beams, which in turn were securely
tied down to the strong floor [Fig. 2(b)].
The two-planes placed in parallel in thelongitudinal direction were nearly identical, but one
plane, called the “South” plane, had a floor slab
extended on the exterior side by 1.5 m, while theother plane, called the “North” plane, had a floor slabthat terminated at the beam end (Fig.1). Thisoverhang was designed to make it possible to directly
measure the effects of RC floor slabs from thedifference in resistance between the two planes. The
columns were extended to the approximate midheight in the third story, at which level steel braces
were connected horizontally to the columns by highstrength bolts through gusset plates. The braces
served to achieve a rigid-diaphragm action in this

3. Loading Program
As shown in Fig.1, two quasi-static jacks werearranged for horizontal loading. They had a 3 MN
force capacity and 800 mm stroke capacity. Eachjack was placed at one end of the test structure and at
the mid-height of the third story. An identical3

Displacement
Amplitude
(rad)

1/200

1/100

1/75

1/75

1/50

1/25

1/25 to 1/15

Cycle

with ALC Panel

Figure 4: Loading Program
displacement was applied to both jacks.
As
explicated later, the two planes, taking the same
displacement at the top, acted nearly independently;that is, no transfer of the force between the two planes
was observed. This means that the load applied toeach jack was the same as the force sustained by theconcerned plane.
Figure 4 shows the loading
program used in the test. Quasi-static cyclic loadingwith increasing displacement amplitudes was adopted,
and either two or three cycles were repeated for each
amplitude. The displacement was expressed interms of the overall drift angle, defined as thehorizontal displacement at the loading point relative
to the loading height (i.e., 8.5 m). Overall drift
angles of 1/200 rad, 1/100 rad, 1/75 rad, 1/50 rad,1/25 rad, and 1/20 rad were adopted. An on-line
pseudo dynamic test was also conducted in themedium range of loading (after the 1/75 rad
amplitude loading and before the 1/50 rad amplitude
loading). After loading to the 1/20 rad amplitude,
the jacks were dismounted once, and installed again
with a 0.6 m long shim, and reloaded again to the
maximum overall drift angle of 1/15 rad to examine
the failure behavior.
A computer controlled on-line test system wasused for the test. The system consisted of quasistatic jacks, load cells, digital displacementtransducers, pump units equipped with inverter
motors, controllers that controlled the pump units, a
PC, called PC for Control, that supervised thecontrollers, and another PC, called PC for Operation,that was connected to PC for Control and commanded
and sent displacement signals to PC for Control. PC
for Operation was also connected on-line with a datalogger having a scanning frequency of 1 kHz. The
PC supervised the entire test operation to makeloading and measurement fully automatic. The
system was also capable of conducting the on-line
pseudo dynamic test by running a program that solves
the associated equations of motion in PC for
Operation. The full detail of the control system is
described in Nakashima et al., 1995 and Nakashima
and Liu, 2003.

Strain Gauge Force
(kN)
500

-500

500
Jack Force
(kN)
-500

North (1-Story)
North (2-Story)
South (1-Story)
South (2-Story)

Figure 5: Comparison between Jack Force andColumn Shear Estimated by Strain Gauge Reading
4. Measurement

A load cell attached to the head of each jackmeasured the horizontal load applied by the jack. A
digital displacement transducer that had a resolutionof 0.01 mm was used to measure the displacement of
the jack. Four strain gauges were glued on thecolumn surface at two cross-sections, each located at
a distance of 1 m inward either from the column top
or bottom. The cross-sections remained elastic; thus
the bending moments applied at the cross-sections
were estimated from the corresponding curvatures.
The shear force applied to the column was estimatedas the sum of the two bending moments divided by
the distance between the measured cross-sections.
According to the measured results, the shear force
thus estimated was found very reasonable. Figure 5
shows comparison between the story shear measured
by the jack’s load cell (the horizontal axis) and thestory shear estimated from the strain gauge reading(the vertical axis). They are plotted with respect to thestory shear force at the peak drift angle (Fig.4) andwith respect to the plane (“North” and “South”) and4

the story (first and second stories). All plots arelocated on and around the line inclined by 45 degreesof the horizontal axis, meaning that both story shears
are very close to each other. The column axial force
was estimated from the average of the strains
measured by the column strain gauges. The beam
shear force was estimated from the difference
between the axial forces exerted into the two columns,
one located on the top of and the other locatedunderneath the concerned beam.
Shear
deformations of the panel zones, deformations of thefloors in the direction orthogonal to the loading
direction, rotations and lateral displacements of thecolumn bases, and out-of-plane rotations anddisplacements of the beams were also measured bydisplacement transducers having a variety of gauge
lengths. Furthermore, many strain gauges wereglued on the beam flanges and webs in the vicinity of
beam-to-column connections as well as on the anchor
bolts at the column bases. These gauges were used
to obtain information on local strains anddeformations.
Summing all the displacementtransducers and strain gauges, a total of 283 datachannels were connected to the data logger, which inturn was connected on-line to PC for Operation.

Force (kN)
1000

-0.04

0.04
Drift Angle
(rad)

-1000

Figure 6: Total Load versus Overall Drift
Angle Relationshiprelationships shown in Fig.7, those obtained from thetests with ALC panels were excluded. For theloading not smaller than the 1/75 amplitude, beams,
panel-zones, and column bases sustained plastic
deformation, which indicates the balanced
participation of individual components to the overall
deformations. Pinching behavior in the second andthird cycles relative to the first cycle was notable forthe 1/75 amplitude and greater. This was primarily
due to yielding and progress of plastic deformationsof the anchor bolts. Such yielding was accepted indesigning the test structure.

5. Test Result
5.1 Cyclic Loading Test
Figure 6 shows the relationship between the total
force versus the overall drift angle, plotting the curves
for loading from the amplitudes of 1/200 to 1/20 rad.
Here, the total force was the sum of the loads appliedby the two jacks. The solid monotonic line was ananalytical curve obtained from pushover analysis,
which was conducted in the course of designing thetest structure.
In the analysis, the effect ofcomposite action between the wide-flange beam andRC floor slab was allowed for by multiplying thebeam bending capacity by 1.5 times for positive
bending (the bending in which the RC slab sustained
tension). The analytically predicted initial elastic
stiffness matched closely the experimental initialelastic stiffness, with the difference not greater than8%.
The analytical maximum strength wasreasonably close to the experimental maximum
strength, although the experimental strength revealed
significant cyclic hardening (by about 30% beyond
the yield strength). The results of Fig.6 suggest that
nonlinear pushover analysis commonly used forseismic design practices is reasonable to predict theelastic stiffness and to estimate the maximum strengthwith some conservatism.
Figure 7 shows the story shear versus story
displacement relationships. The relationships arepresented with respect to the story (the first andsecond stories) and plane (the “North” and “South”
planes). The story shear force was the load appliedby the jack placed in the concerned plane. In the

5.2 Fractures and Failure
Small but visible cracks started during the cyclesof the 1/25 amplitude and grew either from the toe ofthe weld access hole or from the edge of the runoff
tab at a few beam ends. These cracks had no visible
effects on the global behavior as shown in Figs.6 and7. During the first cycle in the positive loading of
the 1/20 amplitude, the “North” plane’s second floor
beam was fractured from the beam bottom flange at
the connection to the exterior column located on theloading jack’s side (Fig.8). The fracture caused asudden drop of the “North” plane’s resistance by
about 15% [Fig. 7(a)] but the incremental stiffness forthe succeeding loading was positive again. Figure 9shows the moment diagrams of the “North” plane justprior to the fracture of the beam flange [Fig. 9(a)] andright after the fracture [Fig. 9(b)]. The bending
moments at member ends were estimated from thecolumn shear and axial forces, as noted in Section:
Measurement. The numbers inserted in the figure
indicate the bending moment values at respective
positions. A significant reduction in the bending
moment is naturally observed at the fractured beanend, which also induced significant reduction in thebending moments at the first story’s column top andsecond story’s column bottom, both connected to the5Force (kN)

Force (kN)

500

500

-0.04

-0.04

0.04

0.04

Story Drift Angle(rad)Story Drift Angle
(rad)

-500

-500
North
(1-Story)South(1-Story)(a) First Story in “North” Plane(b) First Story in “South” Plane
Force (kN)

Force (kN)

500

500

-0.04

-0.04

0.04

0.04

Story Drift Angle(rad)Story Drift Angle
(rad)

-500

-500

South
(2-Story)

North(2-Story)(c) Second Story in “North” Plane(d) Second Story in “South” Plane

Figure 7: Story Shear versus Story Drift Angle Relationships

Second floor beam

Exterior column

Figure 8: Fracture at Beam Endal., 2000.
Figure 10 shows the story shear versus story drift
angle relationship for the last portion of loading withlarge drift angles. The first story shear decreased
significantly with the increase in story drift angle
from 1/20 to 1/8 rad [Fig. 10(a)], whereas the second
story was unloaded [Fig.10(b)]. Formation of afractured beam end. It is notable that the bending
moment values did not change much in all otherlocations. This indicates that effects of one fracture
remain rather local, confined primarily in the vicinityof the fracture location.
This observation isreasonable in light of the classical St. Venant’s
principle, as analytically explicated by Nakashima et

6Loading

Loading
111

402

262

412 203313 424

158

115

209

140

395

297

79 14

326

265 404

502

321

93

171

257

208

150

436 316451

304 455

165 99234

148

395 332500

256 405

515 569

254

199

217

174

80

(a) Before Fracture(b) After Fracture
Figure 9: Moment Distribution Before and After Beam Fracture (unit: kN×m)

Beam
ColumnForce (kN)

Force (kN)

1000

1000

-0.1

-0.1

0.1

0.1

Story Drift Angle(rad)Story Drift Angle
(rad)

-1000

-1000
1-Story

2-Story(a) First Story(b) Second Story
Figure 10: Unstable Behavior in Formation of First-Story Collapse Mechanism

Second floor beam
Local buckling

Figure 11: Local Buckling at First Story Column Top

column’s inflection point lower and increased thebending moment at the column top, which eventuallyreached the plastic moment.
The first story’s
unstable behavior was accelerated because of local
buckling at the column top (Fig.11). The width-tothickness ratios of the first story columns were 25(interior columns) and 33 (exterior columns), which

first-story collapse mechanism was the primaryreason for the drop in resistance. The moment
resistance of the column bases decreased seriously
during the last-stretch of loading, because of the
combined effect of plastic elongation of anchor bolts
and the crash of concrete placed underneath thecolumn base plates. This decrease moved the7were not compact in the classification of AISC 2000
Seismic Provisions.

the RC floor slabs), and twice the difference wastaken to be the increase by the composite action.
Table 2 summarizes the increase of strength andstiffness by the composite action thus estimated.
Composite action led the test structure to an increaseof the elastic stiffness (during the 1/200 rad
amplitude) by about 30%. The action became lessnotable with the increase in amplitude most likely
because of cracks accumulated in floor slabs. Under
the 1/25 rad amplitude, the effect was reduced to 5%.

5.3 Composite Actions
Figure 12 shows the crack patterns observed up
to the overall drift angle of 1/25. The three lines ofcracks running horizontally (from “North” plane to“South” plane) were the shrinkage cracks present
prior to loading. These cracks ran on top of theorthogonal beams where shear studs were arranged.
To the overall drift angle of 1/25, cracks wereaccumulated along the longitudinal beams andextended approximately 1 m on both side of the beam.
Although preliminary, the effect of composite action
was estimated as follows. The difference in stiffness
and strength between the “South” and “North” planes
was taken to be half the composite effect in that the“South” plane had the floor slab on both sides of thebeam, whereas the “North” plane had the floor slab
only on one side. Thus, the “North” plane’s strength(or stiffness) minus the difference of strength (orstiffness) between the two planes was taken to be thestrength (or stiffness) of the bare steel frame (without“South”

5.4 Interaction with Exterior Finishes
The effects of exterior finishes on the stiffness
and strength of the tested frame were observed by the
direct comparison between the tests with the 1/75 and1/25 amplitudes, because for those two amplitudes,
tests were conducted one time without the ALC
panels and the other time with them. The panels
were attached to the edge beam of the “South” plane.
Configuration of the ALC panels and the attachment
details are shown in Fig.13. The ALC panels had awidth of 600 mm, a height of either 3,500 mm (thefirst story) or 3,960 mm (the second story) mm, and a“North”“South”“North”

1m

1.5m 1.25m 1m

1m 1.25m(a) Positive Loading(b) Negative Loading

Figure 12: Cracks Formed During Loading
Table 2: Summary of Composite Action With Respect to Cyclic Amplitude
Bare frame

Composite
effects

Total

Percentage inincrease

Initial stiffness (kN/mm)

4.3

1.2

5.5

28%

1/200 (kN)

183

50

233

27%

1/100 (kN)

369

52

421

14%

1/75 (kN)

489

44

533

9%

1/25 (kN)

571

30

601

5%

8

500
30 10 3960
980

3500

1300
3500
4450

300

5700
6000

300

300

5700
6000

300

(a) Elevationbolt

anchor150
32.5 117.5

32

14

welding
welding
×65×6
L-65
L-65×65×6

second 80
floor 1080

150

bent plate
pedestal platesealing

r=7

675
flat plateflat plate

95

120

H-300
×150×6.5×9
H-300×150×6.5×950 20 50

25

r=7.5

anchor

12.5 25

fill

75
66
bent plate

50 50 35(b) Attachment to Edge Beam(c) Plates with Slotted Holes

Figure 13: Installation of ALC Panels

Force (kN)

Force (kN)

500

500

-0.04

-0.04

0.04

0.04

Story Drift Angle(rad)Story Drift Angle
(rad)
-500

-500

South
(2-Story)South(1-Story)(b) Second Story(a) First Story

Figure 14: Effect of ALC Panels on Hysteretic Behavior(Solid Lines = without Panels; Dotted Lines = with Panels)

9(a) Inclination of ALC Panels(b) Cracks and Spalling of Concrete(1/25 rad Drift)
at Panel Bottom
Figure 15: Deformation of ALC Panels
thickness of 100 mm [Fig. 13(a)]. Each panel had astud bolt embedded in the mid-width location near the
top and bottom edge. The bolt was inserted to theslotted hole of a small steel plate [Fig.13(c)]. The
plate was welded to a small angle, and the angle waswelded to the edge beam [Fig. 13(b)], both prior to
the installation of the ALC panels. The slotted holes
were used to ensure rigid movement of the ALC
panels during the horizontal response of the frame.
This detail has been adopted widely in Japan
particularly after the 1995 Kobe earthquake, in whichquite a few damage instances were observed for ALC
panels (Reconnaissance 1995).
Figure 14 shows the “South” plane’s story shear
versus story drift relationships obtained for the two
amplitudes, with the solid lines without the ALC
panels and the broken lines with. As evidenced
from the figures, the ALC panels did not affect either
the stiffness or strength for both amplitudes.
Product specifications of ALC panels commonly
specify an allowable story drift of 1/75 to 1/50 for use
in practice.
The test results showed excellent
performance of the ALC panels and adequacy of theattachment details [Fig. 13(b) and (c)]. No visible
cracks were observed in the ALC panels except forminor cracks and spalling of concrete at the bottom of
the panels in the first story (Fig.15). At this location,
there were inevitable contacts between the panels andthe pedestal angle when the panels rotated.
6. Conclusions

yielding of the anchor bolts) were observed.
Pinching behavior was notable for cyclic loading withlarger amplitudes (up to 1/25 in the overall drift
angle) primarily because of cyclic yielding andresulting slip-type hysterisis experienced at thecolumn bases.
(2) A beam fracture caused changes in thebending moment distribution, but the effects wereconfined primarily in the vicinity of the fractured
beam. This observation was consistent with theclassical St. Venant’s principle.
(3) Although the column-to-beam strength
ratio was not smaller than 1.9, the final failure
occurred by the formation of a first-story collapse
mechanism. The mechanism was formed as a resultof significant reduction in strength and stiffness of thecolumn bases under large rotations and accelerated by
local buckling of the column tops in the first story.
(4) The degree of composite action changed inaccordance with the deformation amplitude; increases
in strength became less notable (meaning that thecomposite effect decreased) for larger deformation
amplitudes. This observation was understandable inreference to the accumulation of concrete cracks
during cyclic loading with increasing amplitudes.
(5) The effect of ALC panels (used for exterior
finishes) on the structural behavior was nearly null up
to the story drift angle of 1/25 rad, indicating that theattachment details adopted for installation of ALC
panels were very satisfactory in terms of thedetachment of the panels from the frame response.

This paper introduced the outline andpreliminary results of the cyclic loading tests applied
to a full-scale, three-story, two-bay by one-bay steel
moment frame. Although detailed data processing,interpretation of the results, and post-analyses are stillin progress, the writers obtained the following notable
observations.
(1) Balanced deformations between the beams,
panel-zones, and column bases (primarily due to

Acknowledgements
This research was supported by the Japanese
Ministry of Education, Culture, Sports, Science andTechnology (MEXT) 21st Century COE Program for
DPRI, Kyoto University (No.14219301, Program
Leader: Prof. Yoshiaki Kawata). The test presented in
the paper was also part of a research projected
entitled “Development of reliability seismic design inconsideration of uncertainties associated with both10

demand and capacity of structural systems.” The
third writer was the principal investigator of thisproject, and it was sponsored by the Ministry of
Education, Culture, Sports, Science and Technology(Basic Research Category S: 14102028). The writers
express their gratitude for the sponsorship. The
writers are also grateful to Prof. K. Inoue of Kyoto
University and Messrs. Y. Fujita and T. Arai of
Obayashi Corporation for their continuous support on
the design, construction, instrumentation, and loadingof the test structure.

Cyclic Loading”, Journal of Engineering
Mechanics, ASCE, (submitted for publication).
Nakashima, M., Minami, T., and Mitani, I. (2000),“Moment Redistribution Caused by Beam Fracturein Steel Moment Frames”, Journal of StructuralEngineering, ASCE, Vol.126, No.1, January 2000
(pp. 137-144).
NEHRP Recommended Provisions for Seismic
Regulations for New Buildings and Structures.
(2000), FEM368, Federal Emergency Management
Agency, Building Seismic Safety Council,
Washington, D.C.
Notification No.1457-2000, Technical Standard for
Structural Calculation of Response and Limit
Strength of Buildings. (2000), Ministry of Land,
Infrastructure and Transport (in Japanese).
Performance-Based
Seismic
Engineeringof
Buildings. (1995), SEAOC Vision 2000 Committee,
Structural Engineers Association of California,
Sacramento CA.
Recommended Seismic Design Criteria for New Steel
Moment-Frame Buildings. (2000), FEMA350,
Federal Emergency Management Agency, Building
Seismic Safety Council, Washington, D.C.
Reconnaissance Report on Damage to Steel Building
Structures Observed from the 1995 HyogokkenNanbu Earthquake. (1995), Steel Committee of the
Kinki Branch of the Architectural Institute of Japan,
Osaka.

References

Midorikawa, M., Okawa, I., Iiba, M., andTeshigawara, M. (2003), “Performance-Based
Seismic Design Code in Japan”, Earthquake
Engineering and Engineering Seismology, Taiwan,
Vol.4, No. 1 (pp. 12−25).
Nakashima, M., Akazawa, T., and Igarashi, H. (1995),“Pseudo Dynamic Testing Using Conventional
Testing Devices”, Journal of Earthquake
Engineering and Structural Dynamics, Vol.24,
No.10 (pp. 1409-1422).
Nakashima, M., Inoue, K., and Tada, M. (1998),“Classification of Damage to Steel Buildings
Observed in the 1995 Hyogoken-Nanbu
Earthquake”, Engineering Structures, Vol.20, No.46 (pp. 271-281).
Nakashima, M., and Liu, D. (2003), “Instability andComplete Failure of Steel Columns Subjected to

要 旨
鋼構造物の耐震能力を定量化するため，3層実大鋼構造骨組を対象に，それが耐力を失うまでの挙動を実験的に検証した．耐震設計で考えられる変形領域までは，骨組各部材はバランスよく変形した．しかし，より大きな変形領域では柱脚部の降伏によるピンチング効果が現れ，さらに床スラブと梁の合成効果が低減した．最後に柱脚損傷の蓄積が柱降伏型の1層崩壊を誘発した．ALC版が構造挙動に及ぼす影響は無視できる．
キーワード: 鋼構造骨組; 実大実験; 耐震設計; 合成効果; ALCパネル; 柱脚

11