张鹏

摘要：在城市轨道交通建设中，结构设计方案常涉及到大尺寸开洞结构的受力问题，如盾构施工竖井、轨排工作井等。此类结构由于受吊装构件的特殊要求，对其支护形式有一定的限制，即在较长的范围内不能设置内支撑，结构设计均优先考虑基坑支护独立受力设计方案。但受到周边管线、建构筑物、地层条件以及设计方案其他因素等限制，常有某些轨排井难以采取基坑支护独立受力的设计方案。本文以北京地铁7号线湾子站轨排井为例，对轨排井支护结构的选择及其要点进行了分析，为类似工程设计提供了一定的参考和依据。

关键词：轨排井 锚索 等效弹性支点刚度 平面应变模型

Abstract: in the urban rail transit construction, the structure design is often involves large size distributions of the structure stress issues, such as the shield tunnel shaft, GuiPai work well. This kind of structure, due to the special requirements of hoisting component, the supporting form to have certain restriction, namely in the long range cannot set in support, the structure design have preferred foundation pit supporting force independent design scheme. But pipes, built by surrounding structures, formation conditions and other factors, such as the design scheme limit, often have to take some GuiPai well foundation pit supporting independent force design scheme. This article on the Beijing subway line no. 7 son stood GuiPai well bay for an example, GuiPai well supporting structure selection and points are analyzed, and the design for similar project provides some reference and basis.

Key words: well GuiPai equivalent elastic fulcrum stiffness anchor cable plane strain model

中图分类号： U455.7+1 文献标识码：A文章编号：

引言

在轨道交通建设中，轨排均需通过轨排井由地面吊入位于一定深度的隧道内，由于钢轨的单节标准长度为25m，为满足铺轨需要，单个轨排井井口预留开洞的净长约30m，净宽需3.5m左右。目前对轨排井段的结构设计均优先考虑基坑支护独立受力设计方案，鉴于轨排井基地吊装构件的要求，在较长的范围内不能设置支撑，一般采用“桁架式”悬臂围护结构、围护墙+锚索结构形式等。然而，受到周边管线、建构筑物、地层条件以及设计方案其他因素等限制，常有某些轨排井难以采取基坑支护独立受力的设计方案，必须考虑主体结构与之共同承担荷载。对于结构设计来说，如何选取更加合理的设计方案和计算模型来解决诸如轨排井等大尺寸开洞结构的受力问题是至关重要的。……