Mitigation of Seismic Vulnerability of Prototype Low-Rise Masonry Building Using U-FREIs

Abstract

Seismic vulnerability of a two-story stone masonry building supported on U-FREIs (unbonded fiber-reinforced elastomeric isolators) is evaluated. The prototype building is located in Tawang, India, and is the first such U-FREI-supported prototype masonry building constructed anywhere in the world. The base-isolated (BI) building is numerically simulated by three-dimensional nonlinear finite elements (FEs). Experimentally obtained mechanical characteristics of U-FREIs are used in defining the nonlinear properties of the model used for simulating U-FREIs. Reduction in seismic vulnerability of the BI building as compared to that of a fixed-base (FB) building is evaluated using analytical fragility curves. Significant reduction in probability of exceedance of all the considered damage states of BI buildings is observed as compared to that of FB buildings.