热带地区隧洞不良地质段超前支护技术

Advanced Support Technology for Unfavorable Geological Section of Tunnel in Tropical Area

不良地质段隧洞开挖过程中极易发生坍塌变形,在隧洞开挖过程有较大安全风险隐患。对斯里兰卡KMTC项目1号洞进口不良地质段的开挖支护技术进行了描述分析,结合施工过程中的实际情况,阐述了不良地质段隧洞开挖、支护、特殊地质的处理、施工观测以及施工过程中应该注意的重点事项,其中超前支护尤为关键,有效的超前支护是隧洞开挖顺利进行必不可少的保障。通过采用小导管灌浆方式进行超支护,有效降低了不良地质段隧道开挖的安全风险,为隧洞的顺利掘进提供了保障。

During the excavation of tunnels in unfavorable geological section,collapse and deformation are very easy to occur and there are potential safety risks during the excavation of tunnels.This paper describes and analyses the excavation support technology for unfavorable geological section at the entrance of No.1 Tunnel of KMTC project in Sri Lanka.Combining with the actual situation in the construction process,the paper elaborates tunnel excavation,support,special geological treatment,construction observation and key points that should be paid attention to in the construction process in unfavorable geological section.The advanced support is particularly critical,and effective advanced support is the indispensable guarantee for smooth tunnel excavation.The small conduit grouting method is used for advanced support,which effectively reduces the safety risk of tunnel excavation in unfavorable geological section and provides guarantee for smooth tunnel excavation.