DISTRIBUTION CHARACTERISTICS OF SURFACE DISPLACEMENT DUE TO LATERAL SPREADING OF LIQUEFIED GROUND

This study aimed to characterize the distribution of surface displacement caused by lateral spreading of liquefied ground based on field measurement data. Cases of lateral spreading during the 1995 Hanshin Awaji, Japan earthquake, the 1999 Chi-Chi, Taiwan earthquake, and the 2010 Darfield, New Zealand earthquake were selected for investigation. The displacement distribution was regressed by existing logarithmic decay and exponential decay models and two newly proposed models based on normal and lognormal complementary cumulative distribution functions. The R-squared value was adopted to evaluate the performance of the models for regression analysis. The results show that the logarithmic decay model satisfactorily approximated the surface displacement distribution in most of the cases, and the exponential decay model was applicable for cases that attenuates with distance most significantly near the waterfront. By contrast, the normal and log-normal complementary cumulative distribution functions gave good approximation for the displacement distribution with a double-curvature feature related to the “block-mode” failure. The ratio of the length of laterally spreading area to the waterfront displacement was also examined, and its range in some cases are roughly conformable to existing study whereas is obviously larger in the 2010 Darfield earthquake case.