引松供水工程大直径压力钢管衬砌施工技术

引松供水工程4标段隧洞衬砌形式分为钢筋混凝土衬砌及压力钢管衬砌。钢管衬砌施工段距隧洞出口长度约为5.55 km，钢管衬砌直径为5.61 m，与隧洞内径最小间距仅为30 cm。为解决在狭小空间内大直径钢管运距长、定位精度低、支撑不牢固和拱顶填充不密实等技术难题，通过分析、总结影响压力钢管衬砌快速施工的因素及解决措施，对比研究多种施工方案，结合工程实践，提出并研制液压轨行式钢管运输台车，同时采用自密实混凝土及米字型支撑加固等一系列措施确保压力钢管满足快速衬砌施工的条件。经工程验证，该措施能够有效解决上述难题，不仅提高了施工效率，而且减小了主线工期压力，为本工程的顺利通水奠定了坚实的基础。

Construction Technology of Large diameter Pressure Steel Pipe Lining in Songhua River Water Diversion Project

The lining forms of tunnel in No. 4 Bid Section of Songhua River water diversion project are divided into reinforced concrete lining and pressure steel pipe lining. The length of steel pipe lining construction section is about 5.55 km away from the tunnel exit, the diameter of steel pipe is 5.61 m, and the smallest space between the steel pipe and the inner diameter of tunnel is only 30 cm. In order to solve the technical problems of large diameter steel pipe such as long transportation distance, low positioning accuracy, weak support and insufficient crown filling compactness, the influencing factors affecting rapid construction of pressure steel pipe lining and countermeasures are analyzed and summarized, comparison is made among different construction schemes, a hydraulic rail mounted steel pipe transport trolley is developed, and the self compaction concrete and double cross supporting reinforcement technology are adopted. The practical application results show that by adopting the technologies mentioned above, the construction efficiency has been effectively improved, and the main line construction period has been reduced.