地铁深基坑开挖对邻近桥桩的影响分析

An Analysis of the Influence of Subway Station Deep Foundation Pit Construction on the Adjacent Piles

以沈阳市地铁10号线北大营街站深基坑施工为工程背景,采用数值模拟软件MIDAS GTS NX,建立考虑基坑支护结构、周围土体和高架桥相互作用的三维整体计算模型,把数值模拟值与实际监测数据进行对比分析,验证模型的适用性;研究基坑开挖对桥桩基变形的影响,给出优化方案;建立模拟+预测的信息化施工方案,指导工程实际施工.结果表明:桩基入土深度为1.5倍基坑深度为最优桩基入土深度,此时桩基水平位移均位于控制值的1/2范围内;桥墩距基坑最低标准安全距离为基坑深度的1/2.

Using the deep foundation pit construction of Shenyang metro line 10 as project background and adopting the numerical simulation software Midas GTS NX,the authors established a three-dimensional integral calculation model,the interactions among foundation pit supporting structure,surrounding soil and viaducts being taken into consideration. The numerical simulation value was compared with the actual monitoring data to verify the applicability of the model; the influence of foundation pit excavation on the deformation of Pile foundation was studied,and the optimization scheme was given. The construction plan of Simulation ＋ forecast was established to guide the practical construction of the project. The results show that the soil depth of the pile foundation is 1.5 times the depth of the pile foundation,and the horizontal displacement of the pile is within 1/2 of the control value. The minimum standard safe distance for the piers is 1/2 of the pit depth.