Mechanical Behavior Numerical Simulation of Surrounding Rock for Optimizing Section Shape of Straight Arch Wall Coal Roadway

Taking Sijiazhuang Coal Mine as an example, we established theoretical model to simulate the mechanical characteristics of surrounding rock with different cross-section shapes of roadway. The calculation results show that the effect of rise span ratio on surrounding rock stability of roadway is obvious. With the distance increasing from sidewall, roof and floor, the principal stress increases rapidly, and then gradually reduces to stabilization; the displacement of sidewall, roof subsidence and floor heave reduces gradually to stabilization. While the rise span ratio is 0.4, the stress and displacement of surrounding rock is small, so it is the optimum choice for tunnel design with 0.4 of the rise span ratio.