Energy-based dynamic reliability analysis

Dynamic reliability analysis (DRA) of structures subjected to strong ground motions is one of the most important parts of the safety assessment of structures. So far many DRA methods based on probabilistic theory have been developed. Generally, DRA methods are divided into three phases; seismic hazard analysis, fragility synthesis, and evaluation of probability of failure. In most DRA method, the seismic hazard curves of peak ground acceleration (PGA) or spectral acceleration at a certain period is evaluated to show the occurrence ratio of input motion in the seismic hazard analysis, and, in the fragility synthesis, random vibration theory is adopted to calculate the conditional probability of failure of structures given the occurrence of input motion. Since random vibration theory is developed in the frequency domain, PGAs are transformed into information in the frequency domain by means of introducing so-called peak factors and power spectra. This fact suggests that it is more convenient for DRA researchers to define the seismic hazardous the indices defined in the frequency domain from the first. In this paper, DRAs based on the two indices, i.e. PGA and total energy, are investigated in detail. Through the study, features and issues of DRA based on the total energy (hereafter called EDRA) are clarified from the viewpoint of the responses of the structure. (author)