Soil-rock aggregate is a kind of common geomaterial

especially in southwest of China

there are different genetic types and different scales of soil-rock mixed slopes. The stability of these slopes is very important to the slope safety during the construction and the operation of engineering project. In the traditional slope stability analysis

soil-rock mixed slope is always regarded as homogeneous soil slope

and rock blocks are neglected. By this way

the result of slope stability analysis may have large error. Using digital image processing technique

a soil-rock mixed slope is analyzed

and its microstructure model is built. Then

by using FEM shear strength reduction method

the stability of the slope is analyzed based on its real structure. The results indicate that rock blocks make the internal stress field became very heterogeneous

the sliding zone of the soil-rock mixed slope obtained by shear strength reduction method is very zigzag. The stability factor of the soil-rock mixed slope based on its real structure model is higher than that of homogeneous soil slope.