Enhancing Structural Resilience: Three-Dimensional Seismic Isolation (3DSI) in Practice

Abstract

This research introduces a novel three-dimensional seismic isolator designed to evaluate the coupled horizontal-vertical responses of a five-story building. A comprehensive structural analysis using the OpenSees software was conducted for three distinct structural systems: the traditional Fixed Base (F.B.) system, the Conventional Seismic Isolated (CSI) structure, and the Three-Dimensional Seismic Isolated (3DSI) building. The proposed 3DSI system is based on the utilization of Super-High-Damping-Rubber (SHDR) technology, which is engineered to achieve vertical isolation. This is achieved through the reduction of vertical effective stiffness and the simultaneous increase in vertical effective damping, resulting in the minimization of vertical acceleration imparted to the superstructure. The research findings demonstrate that the 3DSI system substantially decreases both vertical and horizontal responses by up to 65% and 20% respectively when compared to the CSI system. In contrast, both the F.B. and CSI buildings exhibit amplification in vertical accelerations, particularly in the case of long-span beams, leading to extensive non-structural damage. Moreover, the 3DSI system results in reduced compression and tension axial loads, along with diminished story drifts.