Numerical simulation and model test study of mechanism of bolt in deep tunnel

According to rock character of a certain soft rock tunnel of Chongqing,the model material is made from epoxy resin,polyamide,silicom rubber,firming agent of silicon rubber,quartz grit,powdery barite and gasoline.The physical model test of the unreinforced tunnel and bolt-reinforced tunnel are made in the true triaxial model test machine.By using strain measure technology,the strains of key parts of the surrounding rock and the bolt are measured;according to these data,the variability of the stress of surrounding rock and the variability of the axial force of the bolt are analyzed.The numerical simulation are made with the same boundary condition as the model test;according to these data,the plastic zone,stress field and the deformation of the surrounding rock are studied;the variation of the axial force of the bolt is studied.We compare the variation of stress of the surrounding rock and the variation of the axial force of the bolt of the model test with the numerical simulation and draw the conclusion that the two processes coincide with each other.