富水大变形隧道变形机理及控制措施研究OA

The construction of tunnels often encounters various complex geological conditions.To investigate the deformation mechanism of water-rich tunnels,this study takes a tunnel passing through a high-pressure water-rich stratum as the research background.Through field monitoring and numerical simulation,the deformation mechanism of the tunnel is revealed,and corresponding support schemes are proposed.The results indicate that the combination of water drainage and pressure reduction+grouting for water blocking can effectively mitigate the influence of water on tunnel deformation.After draining the water within the boreholes,the tunnel deformation rate decreases.By comparing different support schemes through numerical simulation,the results show that under the passive support of systematic bolts,the deformation of the surrounding rock is relatively large.After replacing them with prestressed anchor cables,the stability of the tunnel improves significantly,with the vault settlement reduced from 50 cm to 10 cm.The surrounding rock of the tunnel is affected by groundwater and in-situ stress,making it prone to intruding into the clearance limit after excavation.By implementing water drainage and blocking measures to reduce the impact of water and using prestressed anchor cables for active support of the surrounding rock to share the load,the stability of the tunnel surrounding rock can be significantly enhanced.The research methods and conclusions can provide references for the safe construction of similar water-rich tunnels.