Non-linear site-specific seismic ground response analysis for port sites in Mumbai, India

Abstract

The site-specific one-dimensional (1-D) ground response analysis of two ports in Mumbai, Jawaharlal Nehru port (JNPT) and Mumbai port; have been performed by using equivalent-linear (frequency-domain) and non-linear (time-domain) approaches. The analysis utilizes site-specific bedrock level input motions developed by deaggregating the seismic hazard at the port sites. The outcome of the ground response analysis is presented through acceleration, strain and stress time-histories at ground surface, peak ground acceleration (PGA) profile along depth of soil deposit, peak spectral acceleration response spectrum and Fourier amplification spectrum. The comparison of the results from equivalent-linear and non-linear approaches in terms of free-field response spectrum and Fourier amplification spectrum shows that the response is nearly same for stiffer site however for soft site; it is overestimated by equivalent-linear analysis. The JNPT site is observed to have higher amplification potential in comparison to the Mumbai port site.