Mapping surface motion parameters and liquefaction susceptibility in Tribhuvan International Airport, Nepal

Abstract

Local site effects and liquefaction are major causes of building and lifeline damage in Kathmandu Valley as depicted by several historical earthquakes including recent 2015 Gorkha earthquake (Mw 7.8). Critical facilities like airports play important role in post-earthquake relief, response and recovery efforts. Tribhuvan International Airport (TIA) is the only international airport in Nepal that is located in alluvial soil deposit regarded as Gokarna formation. To assess the site effects and liquefaction occurrence in TIA, this study performs one-dimensional ground response analysis as well as liquefaction susceptibility analysis using shallow borehole logs. Surface motion parameters estimated from one-dimensional ground response analysis are mapped for 0.3g and 0.5g peak ground acceleration inputs. In addition to this, qualitative liquefaction susceptibility map is prepared considering the liquefaction potential index estimated for each borehole log.