盾构隧道施工对既有桥梁影响及施工监测分析

Influence of shield tunnel construction on existing bridge and construction monitoring analysis

文章采用Midas GTS/NX有限元软件,建立盾构隧道侧穿既有桥梁的施工模型,与合肥某盾构隧道区间侧穿既有桥梁的实际工程结合,对盾构隧道所侧穿桥梁的桥墩沉降、桥墩侧向位移及地表沉降进行数值分析。研究结果表明,盾构隧道侧穿既有桥梁的施工完成后,桥墩沉降、桥墩侧向位移和地表沉降的控制效果较为理想,既有桥梁处于稳定状态。结合现场的监测数据,对监测点的模拟结果与实测结果进行对比分析,结果表明,采用数值计算模型模拟盾构施工对既有桥梁影响的结果是可靠的,可以运用文中数值模拟计算方法预测相似工况下盾构施工所引起的临近既有桥梁的桥墩沉降、桥墩侧向位移和地表沉降。

In this paper,Midas GTS/NX finite element software is used to establish a construction model of a shield tunnel crossing an existing bridge on the side,which is combined with the actual project of a shield tunnel in Hefei City crossing an existing bridge on the side.Numerical analysis of the pier settlement,lateral displacement of the pier and ground settlement is carried out.The research results show that the control effect of the pier settlement,lateral displacement of the pier and ground settlement after the completion of the construction of the shield tunnel crossing the existing bridge is ideal,and the existing bridge is in a stable state.Based on the on-site monitoring data,the simulation results and the measured results of the monitoring points are compared and analyzed.The results of the numerical calculation model are reliable,suggesting that the proposed method can be used to predict the pier settlement,lateral displacement of the pier and ground settlement caused by the shield construction in the vicinity of the existing bridge under similar conditions.