Interface behaviour along the boundary between the rock bolt and bond material

Since conventional tunnelling method has frequently been utilised for many tunnels under severe conditions such as high overburden, extremely shallow depth, excavation close to existing structures, a large cross-section, tunnel support should be carefully designed under those adverse conditions. The authors have been studying about the rock bolt which is one of the essential supports for the excavation. This paper aims to analyse the interface behaviour between the rock bolt and the bond material using both the laboratory tests and the numerical simulations. We mainly focused on the effect of different types/forms of rock bolts with the following design parameters: with/without ribs, rib angle, the strength of bond materials and confining pressure. This study will contribute to the understanding of the rock bolt supporting mechanism and the effects of rock bolting in detail.