Experimental Study of the Shear Strenght of Unfilled and Rough Rock Joints

Abstract: Experimental study of the shear strength of unfilled and rough rock joints Ahmed Elsayed, KTH   A series of shear tests have been performed in order to study the influence of matedness on the shear strength of rock joints. The tests have been performed with different degrees of matedness. The purpose is to analyze if the effect from matedness on the peak shear strength can be predicted by using the criterion proposed by Johansson 2009. The first phase of the study involves the measurement of the surface properties of the rock joints using optical scanning. The second step is the use of the model and the surface properties to analytically calculate all the different parameters and the peak shear strength. In the third step, direct shear tests are performed. The fourth and final step includes the verification and comparison of the results obtained from the model with those of the shear tests. The results from the comparison show good agreement between the conceptual model and the shear tests.