Dynamic Evaluation of PreWEC Systems with Varying Hysteretic Energy Dissipation

Abstract

The precast wall with end columns, known as the PreWEC, was developed as a solution for resisting earthquake lateral loads and validated using quasistatic testing. This paper presents a shake table investigation of this system, which evaluated the performance of four PreWEC test units with total damping varying between 9 and 16% using multiple-level earthquake input motions. Different amounts of lateral resistance were targeted for the four test units by varying key design parameters, including the posttensioning area, location of the end columns, and number of the connectors joining the end columns to the wall panel. Results from this study: (1) confirmed the ability of using PreWECs with different locations for the end columns; (2) validated good seismic performance for all four systems in terms of the maximum transient drift, absolute acceleration, and residual drift; and (3) enabled the response modification coefficient (or R factor) to be expressed for the PreWEC system as a function of available damping. Based on the test outcomes, the procedure for designing PreWEC systems is presented.