明挖基坑开挖卸荷对运营地铁隧道隆起变形影响研究

Study on Influence of Excavation Unloading of Open-cut Foundation Piton Uplift Deformation of Operating Metro Tunnel

结合郑州市某道路工程上跨运营地铁一号线实例,研究基坑坑底加固和分区、分层、跳槽开挖方案引起的地铁隆起变形。研究结果表明:基坑加固法不仅能改善基坑底土体物理力学参数,增大土体抗剪能力,减少变形,而且使隧道上方一定厚度的土体成为整体共同抵抗土体变形,减小了土体变形和卸荷荷载对地铁的影响,保证了地铁的运营安全。

Based on the case study of the cross-operation Metro Line 1 project on the main road in front of the Zhengzhou Railway Station,this paper studies the Metro uplift deformation caused by the foundation pit bottom reinforcement,zoning,layering and hole-jumping excavation.The results show that the reinforcement method not only improves the physical and mechanical parameters of the soil at the bottom of the foundation pit,increases the shear resistance of the soil and reduces the deformation,but also makes the soil above the tunnel with a certain thickness become a whole and resist the soil deformation together so as to reduce the influence of soil deformation and unloading load on Metro and ensure the operation safety of Metro.