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Title: Evaluation of collapse resistance of reinforced masonry wall systems by shake‐table tests
This paper presents a shake-table test study to investigate the displacement capacity of shear-dominated reinforced masonry wall systems and the influence of wall flanges and planar walls perpendicular to the direction of shaking (out-of-plane walls) on the seismic performance of a wall system. Two full-scale, single-story, fully grouted, reinforced masonry wall specimens were tested to the verge of collapse. Each specimen had two T-walls as the seismic force-resisting elements and a stiff roof diaphragm. The second specimen had six additional planar walls perpendicular to the direction of shaking. The two specimens reached maximum roof drift ratios of 17% and 13%, without collapsing. The high displacement capacities can be largely attributed to the presence of wall flanges and, for the second specimen, also the out-of-plane walls, which provided an alternative load path to carry the gravity load when the webs of the T-walls had been severely damaged. The second specimen developed a higher lateral resistance than the first owing to the additional axial compression exerted on the T-walls by the out-of-plane walls when the former rocked. The shear resistance of the T-walls evaluated with the design code formula matches the test result well when this additional axial compression is taken into account. more » However, it must be understood that the beneficial influence of the wall flanges depends on the magnitude of the gravity load because of the P-Δeffect and the severity of damage induced in the wall flanges when the wall system is subjected to bidirectional ground motions. « less
Authors:
; ;
Award ID(s):
1728685
Publication Date:
NSF-PAR ID:
10194587
Journal Name:
Earthquake Engineering & Structural Dynamics
ISSN:
0098-8847
Sponsoring Org:
National Science Foundation
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