Evaluation of Liquefaction Potential of Port Structures with Earthquake Magnitude Adjustment

Abstract

The port structures and breakwaters are frequently exposed to failure under sever seismic loading. One of the main causes of failure is loss of bearing capacity due to liquefaction, which is caused by build-up of excess pore water pressure under repeated dynamic loading. It is thus important to accurately estimate liquefaction susceptibility of port structures. Liquefaction susceptibility is commonly determined by simplified method relating the equivalent shear stress and resistance determined by the standard penetration test. The equivalent shear stress is highly dependent on the duration of the ground motion, which in turn is determined by the magnitude and distance of the earthquake. This study performs deaggregation analysis to determine the representative earthquake scenarios and ground motion time histories for selected probabilities of occurrence and the results are applied to simplified and advanced liquefaction analyses at ports located at southern parts of Korea. Analyses indicate the importance of adjusting the effective stress with the magnitude of the earthquake.