Statistical Rainfall Risk Estimating Method for the Surface Collapse of a Cut Slope


Tomoyasu SUGIYAMA , Hisashi MURAISHI
Slope collapse at embankments and cut slopes along railways sometimes occurs under heavy rainfall caused by typhoons etc. and it influences safe operation of the trains. The practical damage estination method, which accurately predicts the hazard of slope collapse and can be used easily by railway workers, is a desirable development goal.

This paper deals with the method of risk estimation for the surface collapse of a cut slope during heavy rainfall using a multivariate analysis. The critical rainfall is obtained using a combination of an accumulated rainfall and an hourly rainfall, which have the powers 0.2 and 0.9 respectively. It was formed that the hourly rainfall has larger influence than the accumulated rainfall on the surface collapse of cut slopes.

Since it was confirmed that this risk estimation standard agreed with some values observed with the surface collapses, it is suggested that the method can be used not only for planning the disaster prevention along railway right-of-way but also for predicting the cut slope collapse due to heavy rainfall.