Hybrid Simulation of the Seismic Response of Squat Reinforced Concrete Shear Walls.

摘要

Most industrial and nuclear facilities rely on reinforced concrete (RC) structural walls as their primary seismic lateral-force-resisting components. These walls commonly have an aspect ratio smaller than 0.5 and have a very high stiffness and strength. There is a significant uncertainty regarding the behavior of these walls under earthquake loading, their failure modes, and their expected strengths and deformation capacities. Hybrid simulation is an effective experimental method to examine these issues: it enables simulation of the seismic response of squat and thick shear walls without the need to recreate the large mass typically associated with the rest of the prototype structure. A new method for hybrid simulation of the earthquake response of stiff specimens using a high-precision displacement encoder was developed and verified in this study. This method was implemented for hybrid simulation of seismic response of two large-scale squat RC shear walls. In order to examine the response of squat RC walls to earthquake ground motion and to investigate the effect of ground motion sequence, two nominally identically 8-in.-thick models of a prototype 36-in.-thick structural wall, typically found in nuclear facility structures, were tested. Each wall experienced a different ground motion level loading sequence. After an initial combined shear and flexural response, a sliding shear failure occurred at the base of the walls. This response was quasi-brittle: the walls rapidly lost strength with small increments of postpeak strength deformation. A nominally identical specimen was tested at the State University of New York at Buffalo (SUNY Buffalo).