An Investigation into the Shear Strength of Rock Discontinuity

摘要

The determination of shear strength of rock discontinuity surfaces is critical to stability analysis of any rock structure. Historically, the relationship between the shear strength and the applied normal stress has been explained by linear-equation. However for the stress range normally encountered in surface or underground mining excavations, the nonlinear relationship involving parameters of joint roughness co-efficient, joint wall compressive strength and basic friction angle is considered to be appropriate. This non-linear criterion together with the practical methods to determine the value of these parameters has been explained in this article. Also, the method of calculation of the instantaneous cohesion and instantaneous friction angle for a range of normal stresses from the non-linear shear strength against normal stress relationship has been presented. Finally, this ankle includes the results of laboratory analysis carried out on a few rock samples to illustrate the method.