盾构下穿高铁桥群桩基加固技术研究与应用

Research and Application of Reinforcement Technology for Bridge Pile Foundation During Shield Construction Underneath

以南京—高淳城际轨道交通DJ-TA04标施工过程中所面临的连续下穿6座高架桥桩基问题为研究对象,基于ANSYS数值分析软件对未采取任何加固措施的盾构直接穿越方案进行数值模拟,得出盾构施工前必须对高铁桥群桩基进行加固处理。从桥墩承台位移、地表沉降等方面,对比分析了注浆加固、纵梁横撑加固及钻孔灌注桩隔离加固等不同方法的加固效果,最终提出隔离钻孔灌注桩加固方案是本工程的最优选择。通过工程试验对理论研究结论进行了验证。

The problem of bridge pile foundation reinforcement was used as research object, during shield construction underneath continuously in DJ-TA04 standard for Nanjing to Gaochun Intercity Rail Transit. Based on the numerical simulation results for shield directly passing without any reinforcement measures, bridge pile foundation had to be reinforced before shield construction. The reinforcement effect of different methods was comparative analyzed from the aspects of bridge pier displacement, surface subsidence, etc. Result has been put forward that the bored pile isolation reinforcement was the best plan for this project. Theoretical conclusions were verified by the engineering test.