THE INFLUENCE OF GROUNDWATER FLOW ON SLOPE FAILURE UNDER HEAVY RAIN

The effects on slope failure due to seepage flow under the heavy rain are investigated numerically. The numerical modelling simulates the interacting overland flow and groundwater flow. The kinematic wave equation is used to describe the overland flow on the slope. The groundwater flow in sloped soil layer, as governed by the saturated-unsaturated equation, is considered in the model. As the results, in case of concave slope, by accumulating the rain water into lower side of slope, the region of saturated throughflow is increased, and return flow leads to fluidisation of surface layer of slope. These features of groundwater flow have implication for large-scale of slope failure.