城市地铁明挖隧道对高架桥桩基影响的数值分析  

A Numerical Analysis of the Impact of Urban Open Excavation of Subway Tunnels on the Viaduct Pile Foundation

作　　者：吴超俊[1] 

机构地区：[1]重庆交通大学土木工程学院,重庆400074

出　　处：《五邑大学学报（自然科学版）》2016年第3期30-34,共5页Journal of Wuyi University(Natural Science Edition)

摘　　要：为评估明挖地铁区间隧道施工对高架桥的影响,结合重庆轨道交通环线某区间隧道施工,采用有限元分析软件MIDAS-GTS建立了隧道及桥墩的三维模型进行数值模拟,分析了隧道开挖对桥墩、围岩的应力及位移影响.结果表明:隧道开挖后围岩和桥墩沉降的不同,桥梁桩身将受到围岩的负摩擦力作用;隧道开挖在桥墩距隧道近端引起的桩基位移向下,在远端引起的竖向位移向上;开挖荷载对桩基应力影响不仅与桥墩到开挖隧道之间的距离有关,还与桥梁桩基高度有关,隧道支护锚杆最大轴力为7.07 k N能满足安全稳定性的要求.In order to evaluate the impact of open excavation of subway tunnels on viaducts, in light of the construction of a tunnel in a certain section of the Chongqing rail transit loop line, this study constructs a three-dimensional model of the tunnel and bridge piers using the finite element analysis software MIDAS GTS to analyze the impact of the tunnel excavation on bridge piers, stress of the surrounding rock and displacement. Results show that after the excavation of the tunnel, the settlement of the surrounding rock and the piers is different and the bridge piles will be subject to negative friction effect of the surrounding rock; the pile foundation displacement is downward where the tunnel excavation occurs close to the pile and the pile foundation displacement is upward when the excavation occurs at a distance from the pile; the stress effect of the excavation load on the pile foundation is not only related to the distance between the bridge pile and the tunnel being excavated but also to the height of the bridge pile foundation; the maximum axial force of the tunnel supporting is 7.07 kN and can meet the requirement of safety stability.

关 键 词：地铁隧道 明挖 桩基 沉降 数值模拟 

分 类 号：U465.33[一般工业技术—材料科学与工程]