INVESTIGATION OF THE INFLUENCE OF SURFACE ROUGHNESS ON THE SHEAR PERFORMANCE OF ROCK JOINTS

Abstract

The roughness of the joint surface is considered one of the most important factors that affect the shear strength of the jointed rock. The main objective of this research is to investigate the influence of the morphology of the joint surface of jointed rock on the shear performance. The research presents the construction of a tilting test table used in appraising the relation between the joint surface roughness and the friction angle of the joint surface. A numerical study using finite element analysis method is then done to simulate the performance of the jointed rock subjected to shear stresses. The numerical models have been established using specific boundary conditions and loading criteria. The numerical models have been calibrated using the published experimental results performed by Rao et al. (2009). A parametric study for the influence of the morphology of the joint surface on the shear strength is then done using different geometrical models. The thesis consists of six chapters Chapter (1) is the introduction to this research; it discusses the importance, the scope and the main objectives of the research. Chapter (2) is a literature review which briefly discusses through the past researches the different methods in investigating the shear performance of rock joints. Chapter (3) discusses the methodology of the tilting test, construction of the tilting test table and experimenting several specimens with different inclination angles of the asperities. Chapter (4) presents a brief discussion about finite element method including analysis sequence and different types of elements and material models that may be used in the analysis. Furthermore, the