Probabilistic seismic hazard analysis of Iran using reliability methods

Abstract

Structural reliability methods are employed in this paper for nationwide probabilistic seismic hazard analysis of Iran and in-depth seismic hazard and hazard sensitivity analysis of Downtown Tehran. The companion paper proposes two analysis approaches based on reliability methods and presents the technical framework for such analyses. The first approach was based on Monte Carlo sampling reliability analysis, which is employed here to conduct hazard analysis at a grid comprising 3695 sites throughout Iran. The results are used to produce nationwide hazard maps for the peak ground acceleration, spectral acceleration, and cumulative absolute velocity. The other analysis approach employs the first- and second-order reliability methods and importance sampling and is applied to the seismic hazard analysis of Downtown Tehran. This analysis identifies the seismic sources that are most influential on the seismicity of Tehran. In addition, reliability sensitivity and importance measures are employed to identify the most influential sources of uncertainty on the seismic hazard at Downtown Tehran. For instance, they identify the geometry of, and the rupture location on, adjacent faults, the shear wave velocity, and the intra-event residuals of ground motion prediction models as the most important sources of uncertainty.