沉井法工作坑在长输管道顶管施工中的应用

顶管穿越公路、铁路在长输管道施工中得到越来越广泛的应用,尤其是地下水丰富、工作面狭窄地段的公路、铁路穿越,其顶管工作坑的要求相对较严格,广东LNG站线项目输气干线6标段穿越工程,因地处城市管网与江南水网地段,故选用沉井作为顶管作业坑,在沉井内进行管道顶管和焊接作业。文章以该工程为例,介绍了沉井的工艺原理、技术参数、施工流程、技术要点及安全环保措施,分析了沉井下沉过程中的异常情况,提出了预防和处理方法。

Application of Open Caisson as Work Pit in Pipe-pushing Construction of Long Distance Pipeline

An open caisson was used as work pit for pipeline crossing at the sixth bid section of the gas transmission trunk line of the Guangdong LNG station and pipeline project, which is located at the region of urban pipeline network and water network. Pipe-pushing operation and welding operation were performed in the open caisson. Taking this project as an example, this paper illustrates the process principle, technical parameters, constructional procedure, key technical points as well as safety and environmental protection, analyses the abnormity in the course of caisson sinking, and puts forward the prevention and treatment methods.