Research on the Energy Constitutive Model and Static Load Anchorage Characteristics of a Novel Mace-Type Energy Release Bolt

Based on the shortcomings of traditional bolts in the process of supporting surrounding rock, the structural composition and working principle of new bolts have been studied in detail. The working principle of the new bolt is divided into the elastic deformation stage and slip stage, and the energy constitutive equation of the corresponding stage is analysed. Then, Abaqus software is used to numerically simulate the working state of the bolt under static tension. With increasing drawing load, the maximum axial stress of the bolt and the von Mises stress of the surrounding rock first increased and then tended to stabilize, and the maximum axial displacement of the bolt gradually increased. The axial stress of the bolt was concentrated at the damping module, and the stress was mainly concentrated at the front damping module. The deformation of the bolt is mainly concentrated in the damping module of the first section, and the deformation of the bolt decreases rapidly with increasing anchoring depth. On-site pull-out tests confirmed that the drawing force of the new bolt increased by 128% and 24% compared with that of the pipe bolt and the left handed without longitudinal rebar bolt, respectively. The novel bolt has the characteristics of high strength and large displacement, which allows it to support the surrounding rock well and has good application prospects.