Support bearing mechanism and numerical simulation analysis of a tunnel and underground space

Based on theoretical research on multifactor-based surrounding rock pressure calculation for tunnels, this paper considered more comprehensive and reasonable factors in the analysis of co-bearing mechanics, and the range of the resulting surrounding rock bearing results was more in line with observations made during engineering practice. The proposed multifactor surrounding rock pressure calculation theory was analyzed to analyze the bearing mechanism of three different convergent forms in the safe state under the joint bearing of the composite lining support and surrounding rock, and it was clarified that the joint bearing of the surrounding rock and support is the key factor to ensure construction safety. Only in the state of true convergence can the first lining and the second lining played an effective bearing role, which was the key factor to ensure the safety of the project. With data monitoring via a layout of representative pile position sensors of an experimental section in an engineering example, the displacement deformation and surrounding rock pressure of the tunnel section vault, arch waist, arch foot and other parts were measured, and the stability analysis and deformation analysis of the relevant results and temporal curves were carried out. It was concluded that the surrounding rock stress gradually stabilized during the monitoring period and that the settlement deformation of the surrounding rock was obvious and regular. Using numerical simulation, the pressure of the surrounding rock and the overall displacement of the tunnel under different working conditions of the tunnel excavation section were numerically simulated and analyzed, and it was concluded that the numerical simulation results were consistent with the measured values of the test section and that the deformation control, stability and safety of the supporting components on the surrounding rock were obvious.