KINEMATIC SIMULATION OF IRRIGATION-INDUCED LOESS LANDSLIDE IN HEIFANGTAI

This paper aims to study the kinematic features of landslides to assess and mitigate landslide risks. It takes Jiaojiayatou irrigation-induced loess landslide in Heifangtai, Yongjin, Gansu Province as the research object. It is based on engineering geological mapping and soil tests, as well as landslide features analysis. It simulates the whole moving process of the landslide and analyzes the velocity field using the finite-difference-method-based kinematic model. The simulation results show that the velocity field of the landslide can be divided into three stages: the initial acceleration stage, the high-speeding fluctuation stage and the collision deceleration stage. The average velocity in the whole process is about 8.6ms-1,which represents a high-speed moving feature and can cause dangerous results. The velocity at the shear opening from the numerical simulation is 1.2ms-1 higher than that calculated using the ASCE recommended method, 2ms-1 lower than that calculated using the variational method, and close to the lower limit calculated using Pan Jiazheng Method. This study is helpful to the prediction of sliding velocity and influencing area of potential irrigation-induced loess landslides.