Integrated Assessment of Liquefaction Potential and Seismic Ground Response Using Equivalent Linear, Nonlinear, and Finite Element Analyses
摘要
This study evaluated liquefaction potential and seismic ground response at selected locations in the Sikkim Himalaya using simplified empirical and numerical approaches. Standard Penetration Test (SPT)-based analyses were performed to estimate cyclic stress ratio, cyclic resistance ratio, factor of safety, and liquefaction potential index. Ground response analysis was conducted using equivalent linear and nonlinear approaches, followed by finite element modelling for dynamic soil response evaluation. Results indicated that shallow soil layers within depths of approximately 2–6 m were highly susceptible to liquefaction due to low corrected SPT resistance and increased cyclic stress demand. Shear stress and ground acceleration generally increased with depth, while nonlinear analysis predicted more realistic stress redistribution and damping effects compared to equivalent linear analysis. Differences of up to approximately 20% were observed between the two approaches. The results further indicated moderate to high liquefaction severity at several locations, particularly at Pelling and Makha. The integrated framework adopted in this study improved the reliability of liquefaction assessment and gave useful insights for seismic hazard evaluation and geotechnical design in the Himalayan region.