Jianyu Cheng, A. Andreas Koutras, and P. Benson Shing
Jianyu Cheng, Ph.D Candidate, Department of Structural Engineering, University of California, San Diego, La Jolla, CA, USA. j7cheng@eng.ucsd.edu
A. Andreas Koutras, Postdoctoral Rresearcher, Department of Structural Engineering, University of California, San Diego, La Jolla, CA, USA. akoutras@ ucsd.edu
P. Benson Shing, Professor, Department of Structural Engineering, University of California, San Diego, La Jolla, CA, USA. pshing@ ucsd.edu
ABSTRACT
Shake-table tests were performed 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 out-of-plane walls. 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, 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 maximum lateral resistance developed in the
first specimen was close to predicted shear strength given by the formula in TMS 402/602. However, the maximum lateral resistance developed in the second specimen was 18% higher than
predicted, which can be attributed to the additional axial compression exerted on the T-walls by the out-of-plane walls when the former rocked.
KEYWORDS: reinforced masonry, shear failure, displacement capacity, collapse resistance, shake table
