Estimation of probabilistic seismic hazard and site specific ground motions for two ports in Gujarat.

Abstract

Seismic design of modern port sites requires assessment of regional seismicity, site specific ground motions and involves various geotechnical earthquake engineering aspects. Present study quantifies the seismic hazard associated with two most important ports located in the Gulf of Kachchh i.e. Kandla port and Mundra port in Gujarat, India. This study aims to develop site specific seismic ground motions at the two port sites for three different levels of ground shaking corresponding to three earthquake return periods. The site characterization is carried out by using available geotechnical data and estimated shear wave velocity. Uniform hazard spectra and design synthetic time histories for these two port sites are developed by using various equations for ground motion prediction and probabilistic seismic hazard analysis. The obtained ground motions are compared with the provisions of Indian seismic design code IS: 1893 - Part 1 (2002). The site amplification factor is obtained as varying from 1.37 to 1.94 for the frequency range of 1.0 to 2.5 Hz.