Theoretical analysis of anchorage mechanism for rock bolt including local stripping bolt

摘要

We have proposed a theoretical model for the analysis of bolt anchorage effects through cross-section uniformity and elastic theory. When the surrounding rock and soil are fixed, then the slip resistance forces directly proportional to the displacement of the bolt. An equilibrium differential equation for the wholly bolt has been established. The axis stress expression has been presented from the combined boundary conditions. It is a monotonic function which consists of negative index and minus index function of the distance, away from the force. The effects of friction proportional coefficient and radius have been analyzed as well. For local stripping bolt, a different model having separate parts has also been analyzed. We have also deduced the axis stress distribution function. Moreover, the curves of different separate conditions were compared which conclude that there is a terrace for the separate part. The longer the separate part, the quicker the axis stress decreased. Finally, an experiment has been performed which show the distribution of axis stress has the same trend with the strain gauge record. The theory solution of axis stress is also proved to be reasonable.