Preliminary study on the development characteristics and formation mechanism of Hanjiashan landslide in Datong county

Through field investigation,we studied the basic developmental characteristics of Hanjiashan landslide,discussed the factors affecting the formation mechanism of the landslide,and analyzed the stability of landslide through numerical simulation.The result indicated that the landslide was an old one,and had slidden once again in 1978,and which is in stable condition currently,but the security reserves for this landslide zone is insufficient.The numerical results have shown that landslide is likely to be unstable as a whole under the rainfall intensity of 80mm/24h and the 48h duration; if the seismic acceleration reached from 0.10g to 0.15g,the landslide would occur overall slide.