盾构穿越既有建筑物施工关键技术研究  

Research on Construction Key Technology of Shield Tunnel Passing Through Existing Buildings

作　　者：刘兴福 LIU Xingfu(China Railway Construction Chongqing Regional Headquarters Co.Ltd.,Chongqing 400039,China)

机构地区：[1]中国铁建重庆区总部,重庆400039

出　　处：《铁道建筑技术》2021年第4期97-100,共4页Railway Construction Technology

摘　　要：对于基础薄弱的既有建筑物,盾构开挖土体过程中易对其稳定性造成威胁,当地层条件复杂时,现有理论不足以解决该类问题。为探究富水圆砾地层条件下盾构穿越既有建筑物对地层及建筑物的影响,采用数值模拟与现场监测相结合的方法,建立盾构隧道三维有限元模型,通过对比数值模型与实际工程相应位置处监测点的竖向位移随开挖距离变化的关系曲线,验证了所建有限元模型的可靠性。盾构掘进易导致隧道横断方向约30 m的沉降槽,建议在该范围内加密布置监测设备。由现场实测数据可知,盾构在富水圆砾地层中沿非直线路径掘进时,对地表建筑物产生的影响较小,所得施工经验及控制措施可为类似工程提供借鉴。For existing buildings with weak foundations,their stability is easily threatened in the process of shield excavation.When the local layer conditions are complex,the existing theories are not enough to solve such problems.To explore the influence of shield tunnel passing through existing buildings on the strata and the buildings under the condition of water-rich and round gravel strata,the combined method of numerical simulation and field monitoring was adopted.Firstly,the three-dimensional finite element model simulating shield tunnel excavation along a curved path was established.Then the reliability of the finite element model proposed in this paper was verified by comparing the results obtained by these two methods,which illustrated the variations of vertical displacement with excavation distance at the corresponding locations in the numerical model and the actual engineering,respectively.Shield tunneling could easily lead to a settlement groove of about 30 m in the cross-section direction of the tunnel.Within the confines,the monitoring facilities were proposed to be densely covered.According to the field measured data,the shield tunneling with the nonlinear path has little influence on the surface buildings in the water-rich and round gravel strata,and the corresponding construction experience and control measures are worthy of reference.

关 键 词：圆砾地层 盾构掘进 曲线路径 建筑物 有限元模型 现场监测 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]