特大盾构江中近距离下穿供水管道的风险设计

珠海十字门隧道下穿马骝洲水道入海口,为国内最大盾构隧道之一,管片外径15.2m。海中盾构段近距离下穿对澳供水管,净距3.79m,环境敏感,风险高,给对供水管道带来一定的影响,工程风险具有一点挑战性。针对这一现状,提出了一种基于施工、监测及风险分析于一体的设计方案,即利用一种基于布里渊光频域分析技术的(BOFDA)的光纤感测技术对供水管进行全自动化监测,对供水管的变形位移进行风险分析,并结合风险分析及时调整盾构掘进过程中施工控制,严格控制掘进面压力平衡,实现均衡、匀速的穿越,及时进行同步注浆与二次注浆的施工方案。

Zhuhai Cross Gate Tunnel, one of the largest shield tunnels in China, is one of the largest shield tunnels in China, with an outer diameter of 15.2m. The shield section in the sea runs through the Australian water supply pipe at close range, the net distance is 3.79m, the environment is sensitive, the risk is high, which brings certain influence to the water supply pipeline, and the engineering risk is a little challenging. In view of this situation, a design scheme based on construction, monitoring and risk analysis is proposed, that is, an optical fiber sensing technology based on brillouin optical frequency domain analysis(BOFDA) technology is used to monitor the water supply pipe automatically. The risk analysis of the deformation and displacement of the water supply pipe is carried out, and the construction control in the process of shield tunneling is adjusted in time in combination with the risk analysis, the pressure balance of the excavation surface is strictly controlled, and the balanced and uniform passage is realized. The construction scheme of synchronous grouting and secondary grouting is carried out in time.