北京地铁工程邻近桥桩施工风险评估及控制对策探讨

A study on risk grade classification method and disposal measures for adjacent bridge piles in Beijing metro engineering

探讨了北京地铁工程邻近桥梁施工风险等级划分应考虑的因素和风险等级划分方法,建议以桥基与地铁工程开挖影响破裂面的位置关系和桥基与地铁工程的水平距离作为主要依据,确定桥梁邻近等级。在此基础上,综合考虑桥梁现状质量,确定邻近桥梁的施工风险等级,并对不同的风险等级给出了相应的邻近桥梁基础加固保护对策,从而形成了对邻近桥梁的控制与保护技术程序,最后通过一个工程实例介绍了对邻近桥桩的评估及处理。

The influential factors and classification method for risk in Beijing metro engineering are discussed in detail. Firstly, the adjacent grade of the adjacent piles must be determined. Two factors such as the spatial relationship between bridge piles and the fracture face induced by metro construction and the distance between piles and metro engineering are advised as evaluation indices. Secondly, the residual bearing capacity for adjacent bidge must be evaluated. The risk grade for adjacent bridge piles can be determined based on the adjacent grade being classified and the residual bearing capacity being certain. The different reinforcement measures must be adopted in term of the adjacent bridge piles risk grade. Consequently, the disposal procedure is formed to ensure the safety of adjacent bridge piles. Finally, a construction example for the adjacent bridge piles disposal procedure is described in detail.