Seismic behavior of low-aspect-ratio reinforced concrete shear walls

Twelve low-aspect-ratio reinforced concrete walls were constructed and tested at the University at Buffalo to develop validated equations for peak shear strength and hysteretic rules for nonlinear response-history analysis. The pretest analysis and construction of the walls are described. Global force-displacement relationships are presented. Currently used equations for peak nominal (in-plane) shear strength do not predict the measured resistance of the walls. Out-of-plane forces and deformations affected peak in-plane shear strength. The resistance of the 12 walls degraded quickly with repeated cycling at displacements greater than those associated with peak strength. The initial stiffnesses of the test specimens were substantially lower than calculated using equations in design standards.