Review and Implications of Inputs for Seismic Hazard Analysis

Abstract

In earthquake-prone regions of the world, it is a common practice to assess anticipated hazard severity for land-use planning, emergency management, and structural design load considerations for public safety applications. Generally, strong ground motion hazards would impact a large area, and displacement hazards could affect a relatively small area localized along the fault trace of surface-faulting earthquakes. This section will review inputs for obtaining a generic ground motion as the most pervasive earthquake hazard and that without site-specific considerations. Note that soft soil sites are generally more hazardous than stiff soil or rock sites, and such site-specific conditions should be characterized realistically in practice for ground response analysis. Implications of the inputs for seismic hazard assessed results will be discussed. The hazard assessment is accomplished by performing seismic hazard analysis (SHA) procedures using either a deterministic or a probabilistic approach (Reiter 1990). The deterministic results provide hazards anticipated from the largest potential events and the probabilistic from prescribed recurrent event(s). The ground motion hazard is obtained from the mean or a certain level above the mean as applied to the ground motion prediction equations (GMPEs) in both the deterministic and probabilistic approaches according to policy or guidelines.