Experimental and numerical investigations on mechanical property and reinforcement effect of bolted jointed rock mass

- An optimized DDARF is proposed to simulate failure process and anchorage effect of jointed rock mass.
- This numerical method is verified through an experimental similarity test.
- The one-joint specimen with one rock bolt under 11 schemes are simulated and the optimal reinforcing position is obtained.
- The one-joint specimen with 2 rock bolts under 3 schemes are also simulated.
- To effectively restrain crack propagation using rock bolt will improve surrounding rock mass stability.

The reinforcement for jointed rock mass using rock bolts has always been one of the most effective and economical geo-structural reinforcing technologies widely used in practical civil engineer projects for a long time. In the field of rock mass engineering, the reinforcement effect of the rock bolt(s) on rock mass is much more obvious due to a large number of natural fractures in rock masses. In this paper, an optimized method using Discontinuous Deformation Analysis for Rock Failure (DDARF) is presented to perform numerical investigations on mechanical property and reinforcement effect of bolted jointed rock mass. In order to verify the effectiveness of the proposed optimized DDARF, laboratory experiments using analog material have also been performed. Experimental results are very favorable with those obtained by the optimized DDARF. Moreover, this numerical method has also been employed to study mechanical property and reinforcement effect of rock specimen with single joint and single rock bolt when the joint and rock bolt have different locations in the specimens. The optimal reinforced location for the rock bolt in the specimen has been obtained through the comparative analysis of reinforcement effects under different conditions. The single jointed rock specimens with two rock bolts have also been numerically simulated and the optimal reinforcing location for the rock bolts has also been obtained. It is concluded that this optimized DDARF would provide an alternative effective tool to investigate the mechanical property and reinforcement effect for bolted jointed rock mass.