Resilience-based seismic design of inter-story isolated multi-towers built on large chassis

Abstract

Multi-towers built on top of a metro depot (a large chassis) have become an important trend in transit-oriented development. Inter-story isolation technology is widely used in high-seismic regions to ensure seismic resilience of such buildings. This study focused on resilience-based seismic designs for such buildings. A typical inter-story isolated two-towers built on a large chassis was selected as the study case, based on a statistical survey. Fifteen cases were designed considering different yield ratios of isolation system and stiffness ratios of the upper towers and large chassis. The influence of these two critical design parameters on the seismic responses and resilience was investigated. The seismic responses and components affecting resilient performance were identified. Based on the analytical results, a resilience-based conceptual design method using the recommended value of critical design parameters was recommended. The reliability and high efficiency of this method were verified through a trial design of four inter-story isolated towers built on a large chassis.