A New Approach to Studying the Mechanical Characteristics of the Anchoring–Grouting System in Broken Surrounding Rock

With the increasing depletion of shallow coal resources, deep roadway excavation has become the main direction in the development of coal mining. Due to geological conditions including high stress and extremely broken rock, disasters such as squeezing, bulging, and swelling are widely observed. The anchoring–grouting support method is one of the most effective methods of surrounding rock reinforcement. To study the mechanical characteristics of the anchoring–grouting system in broken surrounding rock, laboratory tests considering the water–cement ratio and preload were carried out. The research results show that the internal force of support and the deformation of the support surface have close relationships with the bearing stages of the anchoring–grouting system. The optimal water–cement ratio and a higher preload can improve the cooperative bearing characteristics of surrounding rock and its support, which is of great significance for enhancing the strength of surrounding rock and reducing roadway deformation. The research results can provide a reference for anchoring–grouting support design in deep roadway excavation.