溶洞注浆加固的空间属性对地铁盾构隧道建设安全的影响效应

Influence of spatial attribute of karst cave grouting reinforcement on the safety of subway shield tunnel construction

依托深圳地铁16号线盾构隧道穿越岩溶溶洞工程,采用数值计算分析方法,建立溶洞注浆加固对地铁盾构隧道建设安全影响的力学计算模型,综合考虑岩溶溶洞注浆加固的空间属性,重点研究不同位置溶洞注浆加固前后对地铁盾构隧道稳定性的影响作用。结果表明:随着溶洞与隧道距离的增加,盾构隧道开挖受未注浆加固的溶洞的影响越来越小;相比于对溶洞不进行处理的盾构隧道开挖,溶洞的注浆加固处理可以有效控制地表沉降,在很大程度上降低了隧道围岩的变形量;相比于对溶洞不进行处理的盾构隧道开挖支护,溶洞的注浆加固在一定程度上改善了盾构隧道管片的受力状态,降低了衬砌结构破坏的可能性。

This research relied on the Shenzhen Metro Line 16 shield tunnel crossing karst cave project,using numerical calculation analysis methods,a mechanical calculation model of the impact of karst cave grouting reinforcement was established on the safety of subway shield tunnel construction.The karst cave grouting reinforcement spatial attributes was comprehensively considered,focusing on the effect of karst caverns at different locations on the stability of subway shield tunnels before and after grouting reinforcement.The research results showed that the shield tunnel excavation was less and less affected by the unfilled cavern with the increase of the distance between the cavern and the tunnel.Compared with the shield tunnel without treatment of the cavern during excavation,the filling and grouting treatment of karst caves could effectively control the surface settlement and reduce the deformation of the surrounding rock of the tunnel to a great extent.The filling and grouting of karst caves improved the stress state of the shield tunnel segments to a certain extent,and reduced the possibility of damage to the lining structure compared with the excavation and support of shield tunnels without treatment of karst caves.