Abstract: Grouting test equipment for cracked rock mass has been developed independently, and grouting reinforcement test has been done on cracked rock mass. Mechanical characteristics and microstructure of cracked rock before and after grouting reinforcement have been explored. Concept of “equivalent layer of bolt-grouting reinforcement”has been proposed. Mechanism of bolt-grouting supporting in deep soft rock roadway has been studied with the method of FLAC3D. Influence of displacement and plastic zone under different thickness, elastic modulus, cohesion and internal friction angle of bolt-grouting reinforcement equivalent layer has been revealed. The paper has shown that as the parameter of the equivalent layer of bolt-grouting reinforcement improves, plastic zone and displacement of roadway surrounding rock have reduces, which has reflected that the grout can improve the integrity and strength of cracked rock mass. Research has laid a foundation for parameter optimization design of bolt-grouting supporting.

Key words: deep, soft rock roadway, bolt-grouting supporting, FLAC3D numerical simulation