RELIABILITY ANALYSIS OF THE VERTICAL PROGRESSIVE COLLAPSE OF BASE-ISOLATED FRAME-WALL STRUCTURES UNDER EARTHQUAKES

Based on the introduction of a seismic damage model of isolators, a reliability analysis of base-isolated frame-wall structures was conducted using the global reliability method. First, the most probable isolators to fail under strong motions were identified by the seismic damage model of isolators. Considering the basic random variables of damaged structures, progressive collapse load factors were then obtained using the random vertical incremental dynamic analysis method. As a global performance parameter, the load factor was adopted in the performance-based seismic fragility analysis. Probability and reliability indices of progressive collapse were determined using the second-order fourth-moment method. On the basis of this method, the probability and reliability indices of vertical progressive collapse were obtained. By using this method, the performance of progressive collapse resistance and structural seismic damage can be acquired.