富水欠固结深回填土地层区间隧道综合施工技术研究

Research on Comprehensive Construction Technology of Interval Tunnels in Rich Water and Unconsolidated Deep Backfill

重庆轨道交通10号线上湾路站—环山公园站区间隧道需下穿富水、欠固结深回填土地层,针对在富水、欠固结深回填土地层采用矿山法长距离修建隧道工程时,可能会发生诸如塌方涌水、突泥等事故,提出了大面域降水井水位自动控制,环形预留核心土法开挖、分层分级控制大变形的双层组合初期支护,新型“桩基+二衬混凝土”的刚性组合及全包防水结构施工,区间隧道狭小低矮空间内密集钢管混凝土桩快速施工和差异沉降理论监测控制等综合措施。经施工组织优化并结合工程实际,证明了综合施工技术具有良好的效果:确保施工质量、提高施工安全、加快施工进度。

The interval tunnel between Shangwan Road Station and Huanshan Park Station of Chongqing Rail Transit Line10 needs to pass through the water-rich and underconsolidated deep backfill layer. When the mining method is used to construct long distance tunnel in the water-rich and underconsolidated deep backfill layer,accidents such as water-gushing from landslide and mud rush may occur.It proposes the automatic control for water level of precipitation well in large area,the reserved core soil excavation,double-layer combined initial support for controlling large deformation by layering and grading,new rigid combination of Pile Foundation and Secondary Lining Concrete and total waterproof structure construction,rapid construction of dense CFST piles in narrow and low space of interval tunnel and monitoring and control of differential settlement theory etc.,which are proved through construction organization optimization combined with engineering practice that comprehensive construction technology has good effects: ensuring construction quality,improving construction safety and speeding up construction progress.