ABSTRACT
In this paper, the author suggests an empirical expression in which the shear strength parameters C, Φ of a layered rock vary with the direction of a plane concerned with respect to the inclination of cleavage. This expression is compared with the experimental results given by former researchers, both are quit close to each other. Using the expression and Mohr-Coulomb criterion and employing a search-try method, it can be judge whether a shear failure plane within the layered rock under three dimensional stresses condition occurs or not as well as what inclination of the failure plane is.
