Analysis on Seismic Response of Base-Isolated Structures with Friction Pendulum System under Bilateral Ground Motions

A bilateral coupled force model is used to simulate the bilateral coupled effect of a friction pendulum system. A comparative study on the unilateral and the bilateral seismic responses of base-isolated structures with friction pendulum system is conducted in this paper. It is found that, under the bilateral ground motions, the acceleration of each floor is reduced; however, the inter-floor displacement of isolation layer becomes larger. Though the inter-floor displacements of super-structure are decreased, the maximum displacement of the bearings under bilateral components is much larger than that under unilateral component. Therefore, the influence of bilateral ground motions on seismic response of base-isolated structures and performance of bearings should be considered during aseismic designs.