Numerical analysis on stability of deep rock roadway based on orthogonal test

In order to solve the problems of the stability of deep rock roadway,based on the orthogonal test method，25 orthogonal experimental models were established by large-scale finite element software,with the four indices of the deformation of two-sides,roof and floor of the roadway and the buckling safety factor as the criterion,the effect of bolt,anchor cable and shotcrete layer three factors on stability of surrounding rock of deep rock was studied.Besides,the methods of variance analysis and multiple regression analysis were applied to fit the mathematical expression between the four indices of the deformation of two-sides,roof and floor of the roadway and the buckling safety factor and the three factors.The results showed that the shotcrete thickness is the key factor affecting the deformation of the roof and the buckling safety factor,the bolt length is the key factor affecting the deformation of two sides and the bottom the roadway.It can significantly improve the stability of the rock roadway while the bolt length is 2.5～3.0 m,anchor cable length is 8～9 m and shotcrete thickness is 100～150 mm.