软土场地钢板桩支护管廊基坑风险分析与对策研究

Potential Risks Analysis and Technical Measures for Excavating Pipe Gallery Tunnel Supported by Steel Sheet Pile in Soft Soil

管廊深基坑工程具有场地空间跨度大、地质条件多变、施工环境复杂等特点,给深基坑的施工安全和周边环境带来诸多不利影响.针对长江漫滩软土场地管廊基坑工程,根据软土的工程特性和二元结构含水层地下水流动特性,考虑钢板桩施工对软土扰动的影响,分析了长江漫滩场地钢板桩管廊基坑施工存在的软土触变、坑底突涌、钢板桩施工等潜在风险,提出了保证基坑施工安全和减小管廊基坑开挖对周边环境影响措施,为软土场地钢板桩管廊基坑工程的合理设计和施工提供指导.

Deep excavation of pipe gallery tunnel has the characteristics of large spatial spans,varied geological conditions and complex construction environment,which brings many adverse effects to the construction safety of deep excavation and surrounding environment.For the excavation of pipe gallery tunnel in Yangtze River floodplain soft soil,according to the engineering characteristics of soft soil and the groundwater flow characteristics of binary structure aquifer,the influence of disturbance of steel sheet pile construction on soft soil was considered.The potential risks,such as soft soil thixotropic,"blowing up"at the bottom of the pit and steel sheet pile construction,were analyzed during deep excavation of the pipe gallery tunnel in soft soil.Technical measures were put forward to ensure the construction safety and reduce the impact of excavation on surrounding environment.Consequently,it could provide guidance for the rational design and construction of pipe gallery tunnel supported by steel sheet pile in soft soil.