Probabilistic Seismic Hazard Assessment and Liquefaction Potential Evaluation for Amaravati Capital Region

Abstract

The present study aims to evaluate the seismic hazard and liquefaction potential for Amaravati capital region (16° 4?–16° 49? N and 80° 7?–81° 2? E) using the latest earthquake data and in-situ geotechnical data. A state-of-the-art Probabilistic Seismic hazard assessment was carried out for the region, and PGA values were obtained for Maximum Credible Earthquake (MCE) and Design-Based Earthquake (DBE) levels, which are 2% and 10% probability of exceedance for 50 years corresponding to 2475 and 475 return periods, respectively. The maximum PGA values at the bedrock level obtained were 0.084 g and 0.172 g for DBE and MCE levels, respectively. Borehole data from 16 different locations were used in the analysis. Liquefaction potential was evaluated using the Seed and Idriss method considering SPT-N values at the site. Liquefaction hazard maps were developed for 3 m and 6 m depths for both MCE and DBE levels. It is observed that the Factor of safety (FoS) against Liquefaction is lesser for MCE ground motion, whereas FoS is higher for the DBE levels. The region was found to be safe against liquefaction for design-based earthquakes, whereas the liquefaction potential was found to be high for maximum credible earthquakes. © The Author(s), under exclusive licence to Indian Geotechnical Society 2024.