Stability Analysis of Surrounding Rock During Construction of Mountain Integrated Pipe Gallery

The stability of surrounding rock is an important concern in the investigation, design, and construction of mountain integrated pipe gallery. On the basis of the DK6+180 section of the Winter Olympics Integrated Pipe Gallery, the stability of surrounding rock was analyzed by using the deformation modulus of surrounding rock obtained by inversion. The results show that with the increase of reduction factor, the strength parameters of surrounding rock decrease gradually, the vault settlement and clearance convergence increase gradually, and the plastic zone range of surrounding rock increases linearly. When the reduction factor reaches 3.5, the plastic zone has penetrated to the surface. At this time, the vault settlement and clearance convergence of surrounding rock are infinite, indicating that the surrounding rock has reached the limit stable state. On the basis of the plastic zone distribution of surrounding rock and the calculation and analysis results of surrounding rock deformation, the stability safety factor of surrounding rock in this section is determined to be 3.5. The research results have reference value for the stability analysis of surrounding rock of similar mountain integrated pipe gallery.