大跨度隧道洞身浅埋偏压段方案比选

论文以汕头至昆明高速公路龙川至怀集段李田隧道右线K106+680~K106+760段洞身浅埋偏压段为工程背景,对浅埋偏压段洞顶反压回填土石方、洞内大管棚超前支护双侧壁导坑法这两种施工方法进行了对比分析。对于如何选择适用以便于操作的施工方法,应根据围岩的类别、水文地质的情况以及工程项目施工现场的实际情况,全面综合考虑。主要从环境保护、施工安全、工程质量、施工进度、工程造价等多方面求得平衡。浅埋偏压段地质条件差,安全因素起主导作用。在此基础上,确定适合本工程的最佳施工方案。

Comparison and Selection of Schemes for Shallow-Buried and Unsymmetrical Loading Section of Large-Span Tunnel Body

This paper takes the shallow-buried and unsymmetrical loading section of the tunnel body of right line K106+680~K106+760 section of Litian Tunnel in the Longchuan to Huaiji section of the Shantou-Kunming Expressway as the engineering background,and makes a comparative analysis of the two construction methods,that is,backpressure backfilling of earthwork at the top of the entrance in the shallow-buried and unsymmetrical loading section and large pipe shed advance support and double side wall heading method in the tunnel.For how to select the applicable construction method for easy operation,it should be considered comprehensively according to the types of surrounding rock,the situation of hydrogeology and the actual situation of the construction site of the engineering project.It mainly makes the balance of environment protection,construction safety,engineering quality,construction schedule and engineering cost and other aspects.The geological conditions of the shallow-buried and unsymmetrical loading section are poor,and safety factors play a dominant role.On this basis,the best construction scheme suitable for this engineering is determined.