Pounding Dynamic Responses and Mitigation Measures of Sliding Base-isolated Concrete Rectangular Liquid Storage Structuress

Abstract

This paper adopts a simplified spring-mass mechanical model for a concrete rectangular liquid-storage structure (CRLSS). Using a nonlinear model to simulate the pounding effect based on the contact element method, the effects of pounding and parameters on the dynamic responses of a CRLSS are studied. Mitigation measures for the pounding effect are investigated. The dynamic responses and the liquid sloshing height are increased after pounding. A parameter analysis shows that impact stiffness, initial gap, peak ground velocity, isolation period, liquid height and length-width ratio (LWR) of the structure are the main factors affecting the pounding response. Certain intermediate gaps can maximize the amplification caused by pounding. The coefficient of restitution (COR) can be reduced by installing a bumper layer, and the COR decreases with an increasing bumper thickness. A reasonable bumper design not only allows the moat wall to limit the displacement but also effectively reduces the structure’s dynamic responses and number of collisions caused by pounding.