Influence of Bolt Pre-tightening Force on Surrounding Rock Stability of Deep Coal Roadways

In view of the high stress and severe deformation of roadway surrounding rock in deep roadways, taking 7434 working face material roadway of Kongzhuang Coal Mine as the model, theoretical calculation was adopted to define the destruction scope of roadway surrounding rock, as well as to analyze the pressure of roadway surrounding rock. The mechanism of surrounding rock controlled by pre-tightening force from the point of view of Mohr-Coulomb theory is anzalyzed, the FLAC^3D numerical simulation method is adopted to simulate roadway support scheme of pre-tightening force. Results show that when bolt pre-tightening force value is 98 kN, roof subsidence value decreases 32.1%, and two sides of roadway moving value decreases 43.8%, the stress state of roadway surrounding rock is improved and the deformation of surrounding rock is controlled.