Measurement of the 3D water flow vector in the Masa]soil slope for predicting slope failure

Akira ENDO and Michiya IRASAWA

Since slope failure induced by heavy rain has recently become a serious problem in Japan, detection of the relationship between the behavior of water flow vector in the slope and the premonitory phenomena of slope failure is attracting increasing attention. However, to date, research on the water flow vector in slopes has not been conducted. In the model experiment using the slope consisting of Masa]soil, simultaneous measurement of the three]dimensional water flow vector and thermal properties based on the quintuple]probe heat]pulse (QPHP) technique was conducted. A high intensity of rainfall (30mm/h) was applied to the slope surface for 39 min by using an artificial precipitation equipment, and then, the creep of slope and behavior of water flow vector in the slope was observed. Although it was not possible to qualitatively determine the relationship between the water flow vector and timing of crack generation in the slope caused by heavy rain, the behavior of the water flow vector was detected.