Effect of fuzzy failure criterion on probabilistic seismic risk analysis under multidimensional performance limit state

Abstract

Traditional probabilistic seismic risk analysis (PSRA) often adopts accurate limit state boundary to define the structural performance limit state, which ignores the fuzziness of limit state thresholds and boundary. In this paper, considering the fuzzy failure criterion, a novel PSRA method based on fuzzy-random hybrid model is proposed under multidimensional performance limit state. A multiple integral formula based on fuzzy failure criterion is established for PSRA, and the influence of different membership functions and membership intervals are studied. A reinforced concrete (RC) frame-shear wall structure is established as the numerical example. The results show that: Fuzzy failure criterion will lead to the change of failure probability, thus the structural potential seismic risk or capacity could be analyzed. With the increase of structural damage degree, the influence of fuzzy failure criterion is become larger. Different membership functions have different effects on vulnerability curves and capacity hazard surface. With the expansion of membership interval, the influence of fuzzy failure criterion on PSRA is getting larger.