1. BEHAVIOR AND RESPONSE OF MODERATE-
ASPECT RATIO RC STRUCTURAL WALLS
Thien A. Tran, Ph.D. Candidate and John W. Wallace, Professor
University of California, Los Angeles
PROJECT DESCRIPTION
 This comprehensive experimental research
program has been conducted to provide insight
into the nonlinear cyclic response of moderate-rise
cantilever walls, including the ability of the wall to
sustain axial load following the onset of lateral
strength degradation.
 The test program includes five large-scale RC
shear wall specimens designed such that
nonlinear shear deformations are expected to
significantly impact wall behavior.
 The test specimens are subjected to a constant
axial load and a single reversed cyclic lateral load
at the top.
 Transverse reinforcement at the wall boundaries
satisfies ACI 318-11 S21.9.6.4 requirements for
special structural walls.
 Primary test variables include aspect ratio (1.5
and 2.0), axial load level (0.025Agf’c and
0.10Agf’c), and shear stress level (4 to 8 ).
 The test specimens are heavily instrumented to
obtain detailed response information, as well as to
provide data for development and validation of
shear-flexure interaction models.
TEST MATRIX
SPECIMEN CONSTRUCTION
TEST RESULTS
FUTURE WORK
ACKNOWLEDGEMENTS
CONCLUSIONS
INSTRUMENTATION
 Significant lateral strength loss at 3.0% drift.
 Various failure modes, i.e., diagonal tension, web
crushing, sliding shear, and buckling of vertical
reinforcement, impacted by aspect ratio, axial load
level, and wall shear stress level.
 Nonlinear shear deformations were from 15%, for
H/L=2.0 walls, up to 50%, for H/L=1.5 walls.
 The detailed test data to be used to validate
models for cyclic shear-flexure interaction.
 Development and validation of cyclic shear-flexure
interaction models
 Loss of axial load capacity
 NSF CMMI-0825347 (NEES Shared-Use)
 NSF Grant 0963183 funded under the American
Recovery and Reinvestment Act of 2009 (ARRA)
 CCF 0755533 (REU) and CMMI-0927178 (REU)
 NEES@UCLA: A. Salamanca and S. Keowen
 UCLA students, NEES and CENS summer
interns: C. Hilson, B. Gerlick, R. Marapao, K.
Pham, G. Schwartz K. Weiland, S. Garcia, I.
Wallace, L. Herrera, J. Diaz, and F. Cifelli
TEST SETUP
Wall RW-A20-P10-S38 and its two
boundary zones at failure
Failure mechanism in wall
specimen RW-A15-P10-S78
Lateral load versus top
displacement for Tests 1 and 2
Lateral load versus lateral
displacement components
for wall RW-A15-P2.5-S64
Percentage of shear
deformation in Tests 4 and 5
LVDT configuration for 2.0 aspect ratio walls
Typical wall construction Special boundary element
(Wall RW-A20-P10-S38)
Test
No.
Specimen Code H/L
t = l
(%)
b
(%)
V@Mn
des
/Vn
des
P/
Agf'c
V@Mn/
Vn
V@Mn/
Acv
1 RW-A20-P10-S38
2.0
0.27 3.23 0.80 0.073 0.81 3.6
2 RW-A20-P10-S63 0.61 7.11 0.88 0.073 0.91 6.1
3 RW-A15-P10-S51
1.5
0.32 3.23 0.80 0.077 0.83 4.9
4 RW-A15-P10-S78 0.73 6.06 0.84 0.064 0.85 7.0
5 RW-A15-P2.5-S64 0.61 6.06 0.79 0.016 0.79 5.8
(b) Shear sliding(a) Diagonal compression
(c) Out-of-plane buckling (d) Side view of the buckling Lateral load versus top
displacement for Tests 3 and 4
Lateral load versus top
displacement for Tests 4 and 5
Wall RW-A15-P2.5-S64 and its two
boundary zones at failure
Lateral load versus lateral
displacement components
for wall RW-A20-P10-S63
Horizontal Load
Vertical Load
Reaction Wall
Out-of-plane
Support
Specimen
'
c
f
Drift Ratio (%)
Lateral Displacement (in.)
LateralLoad(kips)
Sliding Shear
Shear
Flexure
Drift Ratio (%)
Lateral Displacement (in.)
LateralLoad(kips)
Sliding Shear
Shear
Flexure
'
c
f