地铁盾构钢套筒接收施工技术方案研究

Study on Receiving Construction Scheme of Steel Sleeve of Subway Shield

地铁工程盾构接收过程是难度最大、风险最高的环节,由于城市地铁盾构隧道施工地质条件及周边环境复杂,盾构到达接收过程中易发生漏水、涌砂等风险,为确保盾构出洞安全,故选取适当的盾构接收方法便显得尤为重要。以某地铁区间隧道的实际施工情况为背景,针对高承压水地区易发生涌水、涌砂等风险,从工期情况和施工风险两方面分析盾构接收方案,最后采用素墙+钢套筒+辅助降水接收方案。该方案解决了由于前期高压旋喷加固过程中地下连续墙成槽时可能进尺慢、地下连续墙和主体维护结构之间存在缝隙等施工难题,结果表明该方案有效地避免盾构到达接收过程中漏水、涌砂等风险,确保出洞安全。

The receiving process of subway shield project is the most difficult,highest risk field,since complex geological conditions and the surrounding environment of the city subway shield tunneling,water leakage and sand gushing risk easily occurs in shield reaching the receiving process,in order to ensure the shield hole security,so selecting the appropriate method of shield is particularly important. In this paper,based on actual construction of a subway tunnel,this paper analyzes shield receiving scheme from two aspects of risk analysis and construction,finally,the scheme with plain steel sleeve ＋ wall ＋auxiliary precipitation reception is used. The scheme solves some difficult problems,including the solution that the diaphragm wall trenching is slow in the high pressure jet grouting reinforcement,and the gap existing between the main maintenance structure and diaphragm wall. The results show that the scheme effectively avoids water leakage in shield reaching the receiving process and sand gushing risk,which ensures security hole.