岩溶地区浅埋隧道变形分析及处治

Research on deformation analysis and treatment technology of shallow buried tunnels in karst areas

为有效解决岩溶地区浅埋隧道的变形问题,依托贵州省某岩溶地区浅埋隧道工程实例,考虑采用注浆充填和支护加固手段等进行处治,运用MIDAS/GTS有限元软件进行岩溶隧道的围岩变形和支护结构受力分析,并针对该岩溶隧道提出相应的处治措施。研究结果表明:①超前小导管和超前大管棚支护均能有效减小岩溶地区隧道的应力和变形,但超前大管棚的作用效果更明显;②溶洞充填程度越高,隧道变形控制效果越好,完全充填对于控制隧道变形十分重要,故应保障注浆整体质量,以有效控制隧道变形;③综合考虑数值分析结果和工程条件,提出具体的处治方案。以注浆充填隧道下方的溶洞,并结合超前小导管和超前大管棚方法对隧道进行加固处理。

In order to effectively solve the deformation problem of shallow buried tunnels in karst areas,based on the shallow buried tunnel in karst areas in Guizhou province,the slurry filling and support reinforcement are considered to reinforce,the MIDAS/GTS finite element software is used to analyze the deformation of tunnel surrounding rock and the stress of support structure.The corresponding treatment measures are then proposed for the karst tunnel.The outcomes show that:①The stress and deformation of tunnel in karst area can be reduced by using the advanced support methods of the small conduit and large pipe shed,and the effect of advanced large pipe shed is more obvious than that of advanced small pipe;②The higher the degree of cavity filling,the better the control effect of tunnel deformation,the complete filling play significant role to control the tunnel deformation,hence the quality of grouting should be guaranteed;③Considering the results of numerical analysis and the actual situation of the karst tunnel,the treatment plan is proposed.The cavity below the tunnel is grouted and filled,the advanced small conduit and large pipe shed are use to reinforce the tunnel.