Probabilistic Study of Liquefaction Response of Fine-Grained Soil Using Multi-Linear Regression Model

Liquefaction behavior of fine-grained soil is associated with numerous soil parameters; however, over the past few years, importance of plasticity in predicting liquefaction susceptibility of soil has been well established in the literature. Regardless of recent advancements, no evident correlation has been developed between plasticity of the soil and factors of safety against liquefaction. Henceforth, the present study evaluates the effect of plasticity on liquefaction behavior of fine-grained soil for seismically active regions of Bihar (India) by proposing an equation based on multi-linear regression (MLR) analysis for predicting factor of safety against liquefaction (FL). The results of the study are supported by reliability analysis (FOSM) which also establish a co-relation between FL, reliability index (β) and probability of liquefaction (PL). The validation of the results using real liquefaction data obtained from liquefied and non-liquefied sites of Chi-Chi earthquake in Taiwan as well as data from Indo-Gangetic plains has confirmed the consistency of the developed multi-linear regression equation. The study devices a substantial impact in the field of liquefaction prediction for fine-grained soil with moderate to high plasticity and aims to felicitate a significant contribution in the knowledge pool of liquefaction studies. The developed equation may also serve as a guideline for taking critical engineering decisions especially during preliminary design calculations of any civil engineering structures vulnerable to liquefaction. © 2021, The Institution of Engineers (India).