ALTERNATIVE ANALYSIS FOR LIQUEFACTION EVALUATION: SIMPLIFIED METHOD, EQUIVALENT LINEAR ANALYSIS AND EFFECTIVE STRESS ANALYSIS

Abstract

Under strong ground shaking, saturated soil can lose their strength and stiffnesses while pore water pressure can be generated. This phenomenon is called liquefaction, which can cause major damages for buildings, slopes, dams and other geotechnical structures. In this study, three conventional analyses: simplified method, equivalent linear analysis and effective stress analysis, were performed to evaluate liquefaction potential, ground settlement and damage severity. Cone Penetration Test (CPT) data at a borehole near the epicenter of the 2011 February Christchurch earthquake was employed for these analyses. The recording of strong ground motion was used as the input for both the equivalent linear analysis and effective stress analysis, while the maximum acceleration was extracted for the simplified method. Predictions of Cyclic Stress Ratio (CSR), Factor of Safety (FS), Settlement (S), Liquefaction Potential Index (LPI), and Liquefaction Severity Number (LSN) obtained from three methods were performed for a comparison.