河道内大型深基坑施工对临近桥梁的影响分析及对策

目前,城区大型深基坑近距离、平行桥梁施工的情况较为少见,河道内深厚透水砂层具备成槽困难、地下水位高、补给无限等特点,大幅增加了工程难度及桥梁的安全风险。结合北京市某工程实例,围绕现况桥梁的保护,对影响基坑及现况桥梁安全的风险源进行了细致分析,而后结合数值模拟计算,针对性地制定出河道内深基坑临近桥梁施工的相关工程措施。监控数据表明,施工期间桥梁的安全得到了保障,相关工程经验值可供类似工程参考。

Analysis on Influence of Large Deep Foundation Pit Construction in River Channel on Adjacent Bridge and Countermeasures

At present,the construction of large deep foundation pit close to and parallel to the bridges is rare in urban area.The deep and thick permeable sand layer in river channel has the characteristics of difficult grooving,high underground water level and infinite supply,which will great increase the engineering difficulties and the bridge safety risk.Combined with an engineering case of Beijing and according to the protection of existing bridges,the risk sources affecting the safety of foundation pit and existing bridges are analyze din detail.Based on the numerical simulation and calculation,the relevant engineering measures are especially formulated for the construction of deep foundation pit in the river channel close to bridge.The monitoring data show that the safety of bridges during construction is ensured.The relative engineering experience can be referred for the similar projects.