An analytical model for axial performance of rock bolts under constant confining pressure based on continuously yielding criterion

摘要

An analytical model is developed to simulate the load-displacement performance of rock bolts under axial loading based on Modified Continuously Yielding Criterion. Such a model accounts for various surface geometries of rock bolt as well as the various confining pressures at the rock bolt to the grout interface which play significant roles in the behaviour of grouted rock bolts under axial loading. Majority of the defined parameters in the model can be measured within the laboratory environment. The proposed model is validated against the experimental results obtained from FRP and HA25 rock bolts. The good agreement between the experimental results and the analytical predictions highlights the ability of the proposed model to simulate the full loaddisplacement behaviour of rock bolts under axial loading.