岩溶地层中的盾构隧道施工

研究目的：岩溶地层中采用盾构法施工在国内尚属首次。盾构掘进中可能发生盾构机栽头、陷落，地层大量失水、坍塌，严重差异沉降而致隧道结构破坏等事故。对溶洞的空间分布、大小及充填情况，溶洞处理，盾构掘进技术措施3个方面进行深入研究，并组织精心设计、精心施工，以保证施工及运营安全。研究方法：采用多种勘查手段分析岩溶地层，充分注重盾构机及盾构施工的特点，比选、优化设计施工方案。研究结果：顺利完成岩溶段盾构隧道施工，验证了勘查及加固方案，填补了国内的空白。研究结论：综合运用多种探测方法对探明溶洞的分布很有成效；根据盾构施工特点制定地层加固方案并有效实施以及对盾构机设计进行针对性的改进并采取相应的掘进技术措施都是适宜的。

Construction of Shield Tunnel in Karst Strata

Research purposes: It is the first time for China to construct tunnel in karst strata with shield method.In the course of shield tunnelling,shield machine probably fall down and the tunnel structure is probably damaged because of losing much water,collapse and bad differential settlements of strata.The deep researches are done on three fields,namely distribution,sizes and filling of karst caves,treatment of karst caves and technical measures for shield tunnelling for the purposes of making fine design and construction and guaranteeing the safety of construction and operation.Research methods:The analysis is made for karst strata by adopting many integrated survey ways and the construction program is optimised through making comparison of the programs according to the characteristics of shield machine and shield construction.Research results:The successful construction of shield tunnel in karst strata verified the feasibility of the survey and reinforcement programs,which fills the blank in China.Research conclusions:It is an effective way to detect the distribution of karst caves by adopting integrated survey method.All of the strata reinforcing program made with the characteristics of shield construction,the innovation of shield machine and the technical measures taken for tunnelling are suitable.