Deformation And Control Research On Deep Soft Rock Tunnels In No.4Coal Mine Of Pingdingshan Coal Mine Group

An number of research were carried out on the physics mechanism of surrounding rock deformation andcontrol of deep soft rock tunnels through theory analysis, numerical simulation and monitoring data analysis.The results showed that the ground stress is the most important factor influencing deformation of surroundingrock, the deep tunnel deformation is more sensitive to ground stress than the shallow tunnel. The conclusionwas derived that the floor and sides are the main parts of deformation of deep soft rock tunnels, the floor heavecontrol should be reached through the whole interaction of surrounding rock.The opinion was put forward thatthe rock mass strength is much lower than rock strength for deep soft rock, the lesser strength parametersincluding cohesive strength and the friction angle is the important factor leading to large deformation ofsurrounding rock, the surrounding rock control of the deep soft rock tunnels should center on improvingstrength parameters of surrounding rock itself. The three bolting reinforcement support technology was putforward and put into practice accordingly, the scientific nature was verified. The research demonstrated that thethree bolting reinforcement support technology can make the most of self-bearing capacity of surrounding rockand strongpoint of every support structure. This technology can control deformation of deep soft rock tunnelseffectively.