Liquefaction hazard analysis of Varanasi city of Northern India

Seismically induced soil liquefaction is one of the major causes for loss of life and property because of its critical impact and significant destructive nature during and after seismic events. Present study aims to assess liquefaction hazard of Varanasi city which is an important city of Uttar Pradesh, which provides a major contribution to Uttar Pradesh’s politics, education and economics. Standard penetration test (SPT) data and soil characteristics have been used to estimate the liquefaction risk. Analysis has been performed for simulated earthquake along Azamgarh fault for two peak ground acceleration values (0.07 g and 0.2 g) using Liquefaction Potential Index ( \({L}_{{\text{P}}}\) $L_{\text{P}}$ ) and Liquefaction Severity Index ( \({L}_{{\text{S}}}\) $L_{\text{S}}$ ) with Factor of Safety (F.S.) as input. The outcomes are displayed in form of hazard maps of F.S., \({L}_{{\text{P}}}\) $L_{\text{P}}$ and \({L}_{{\text{S}}}\) $L_{\text{S}}$ for different depths. The results reveal that as per F.S. study most of the areas across city are liquefiable at 0.2 g PGA, whereas these are found safe at 0.07 g PGA. \({L}_{{\text{P}}}\) $L_{\text{P}}$ study shows that city belongs to ‘Low to Very Low’ category at 0.07 PGA whereas at 0.2 g PGA areas like DLW Ground, BHU, Lahartara and Sigra fall in ‘high’ category. As per \({L}_{{\text{S}}}\) $L_{\text{S}}$ study, city falls in ‘Very Low’ to ‘Medium’ severity.