Stability analysis of slope with weak interlayer

In geotechnical engineering, the slope stability with weak interlayer is a very important issue. The properties of weak interlayer are not only related to the environmental conditions, but also to their granularity composition and mineral composition. Therefore, select strength parameters of weak interlayer, the factors, such as water content, clay mineral composition and angle of the weak interlayer should be taken into account. In this paper, we define the weak interlayer angle is between weak interlayer and horizontal surface. With the increase of the weak interlayer angle, water in weak interlayer is more easily to outflow, it makes the water content reduce, but strength increase. Under this assumption, the safety factors with different weak interlayer angle have been analysed by FEM which is combined with the UH model. Through studies about a series of slope stability case, we found that the safety factor increases with the increase of weak interlayer angle.