Study on Mechanical Characteristics of Rock Surrounding the Roadway under Different Section Shapes

In order to understand the instability characteristics of surrounding rock during deep roadway excavation, the influence of different section shapes on the stability of surrounding rock was systematically analyzed. Four sections of roadway with circular, rectangular, semicircular arch and three-center arch were studied. Simulation revealed that the maximum principal stress concentration and pressure relief degree of the three-center arch roadway is the highest, the minimum principal stress relief degree of the rectangular roadway is highest, the roof subsidence of the semicircular arch roadway is the lowest, the roof subsidence and left and right side displacement of the rectangular roadway are the highest, the surrounding rock failure areas of the circular roadway are evenly distributed, the surrounding rock failure areas of the other shape roadways are arch-distributed and the surrounding rock failure of the two sides of the rectangular roadway is the deepest. The mining stress environment coefficient is defined according to the stress state of the rock surrounding the roadway, and the range in which the coefficient is greater than 0.2 is defined as the destructive danger area. We found that the stability of the rock surrounding a circular roadway is greater than that of a semicircular arch roadway, a three-center arch roadway and a rectangular roadway.