Abstract
As a result of an investigation on landslides induced by the Yongdeng earthquake in China, 5 kinds of characteristics of landslides induced by the earthquake are summarized as following: a) they often occur in steep slopes from 30°to 45°, b) there are more landslides on convex slope than ones that on concave slope, c) failure surfaces are shallow, d) there are cracks on the upper slope of a landslide, e) landslides more concentrate around faults than the epicenter, etc. Each characteristics is explained theoretically by caulcula-tion on model slopes using a limit equilibrium method of an application of dynamic programming to the Janbu's method which can search the critical slip surface under giving conditions. The influences of such factors as slope angle, slope type, the depth of surface layer, cohesions of surface layer and bedrock, horizontal and vertical seismic forces, are analyzed quantitatively.
