地铁盾构隧道施工对拱桥桥墩的影响分析

Analysis on Influence of Metro Shield Tunnel Construction on Arch Bridge Pier

以城市地铁区间盾构隧道下穿老式砖拱桥为对象,采用三维有限元方法研究了隧道开挖对拱桥桥墩位移和受力的影响。研究结果表明,隧道开挖将会引起拱桥各桥墩产生不均匀沉降,;桥墩自身及桥墩间的不均匀沉降引起了桥墩自身应力的改变,同时由于拱桥结构的特殊性,还将引起拱圈结构受力的改变。建议在施工中采用地层加固等措施以减小隧道施工对拱桥的影响。

Taking the shield tunnel of urban metros underpassing the old-fashioned brick arch bridge as the object, the 3-D finite element method is used to study the influence of tunnel excavation on the displacement and stress of arch bridge pier. The study result shows that the tunnel excavation will cause the non-uniform settlement of arch bridge piers, the non-uniform settlement of pier itself and among piers causes the change of pier stress itself, and the particularity of arch bridge structure will cause the change of arch ring structural stress. It is proposed to take the measures of stratum reinforcement to decrease the influence of tunnel construction on arch bridge in the construction.