暗挖隧道与邻近桥桩距离对桥梁的影响性分析

为探究暗挖隧道与邻近桥桩距离对桥梁的影响,以西安地铁某标段为背景,结合MIDAS/GTS NX有限元软件,建立三维模型进行数值模拟,并利用现场监测数据对比模拟结果,验证模型合理性。通过逐步缩小地铁隧道与桥桩的距离,分别模拟出地铁隧道与桥桩在不同距离下的桥面倾斜变化。模拟结果表明:临近隧道开挖一侧的位移量大于另一侧的位移量;且随着隧道与桥桩距离的减小,这种倾斜差异现象愈发明显;桥梁与隧道临界安全距离为15 m,当隧道与桥桩的距离小于临界安全距离后,随着隧道与桥桩距离的减少,对桥梁可能造成的危害会越大。

Impact Analysis of Subway Excavation Tunnel and Adja-cent Pile Distance on Bridge

To explore the impact of subway excavation tunnel and adjacent pile distance on bridge,a section of subway engi-neering in Xi′an City is taken as the background,and com-bined with the finite element software MIDAS/GTS NX,a 3D model for numerical simulation is established. The simulation results are compared with field monitoring data to verify the accuracy of the model. By shortening gradually the distance between metro tunnel and bridge piers,the tilt changes of bridge deck in different distances are simulated respectively. The results show that the displacement on the bridge side adja-cent to subway tunnel is greater than the displacement on the other side,and with the decrease of the distance between tun-nel and piles,the tilt difference becomes more obvious. The critical safety distance between bridge and metro tunnel is 15 meters, when the distance between tunnel and bridge is less than the critical safety distance,subway tunnel excavation may cause greater harm to the bridge.