Abstract:
Characteristics of the occurrence of coal formation in western mining area are without water in topsoil and has a large amount of water in bedding rock, and the surrounding rock has typical mechanical properties such as low intensity, poor cementation, muddying in the presence of water. Taking Ningxia Maiduoshan Coal Mine as the engineering background, combined with the current situations of fracture development in bedrock, surrounding rock containing a large amount of water, water spraying in roof and water bursting of roadway, water inrush mechanism of surrounding rock were summarized with laboratory experiment, borehole imaging, numerical simulation and field monitoring. Based on the idea of “dredging and blocking, sealing and strengthening”, a joint control scheme for roadway construction of high stress soft rock with serious water spraying was presented, and the control effect of the technology was studied. The results show that the joint control scheme can ensure that tunnel deformation control is in a reasonable range, floor deformation decreases to 28.8%, and the maximum relative displacement of two side walls reduced by 86.7%. The technology can significantly reduce stress concentration, and effectively improve stress state of surrounding rock. The field monitoring data are consistent with the simulation results, which proves that this scheme gets good control effect.