Runout Analysis of Slurry Flows with Bingham Model

Abstract

In this paper, the Lagrangian finite element method is formulated along with the Bingham model for simulating natural transient slurry flows. The numerical model thus developed is validated with available experimental results. As well, a back-analysis of the dynamic behavior of the 1997 Lai Ping Road landslide in Hong Kong is conducted. Correlating well with field observations, the modeling results are satisfactory in terms of predicting the hazard areas of the debris trail during runout and the debris distribution on deposition fan. The present method is also able to demonstrate the multidirectional sliding features of natural slurry flows. It is noteworthy that the availability of high quality data on site topography is crucial for modeling such a gravity-driven flow. A knowledge of dynamic runout information is useful in estimating landslide mobility, potential hazard areas, and debris impact loads, and in evaluating the effectiveness of counter measures in the debris released area, in relation to downslope property development.