地铁车站PBA法施工诱发的地表及桥桩沉降规律研究  

Study on Settlement Regulations of Ground Surface and Bridge Pier Induced by Metro Station Construction with PBA Method

作　　者：任建喜[1] 王松[1] 陈江[1] 孙杰龙[1] 孟昌[1] 朱元伟[1] 

机构地区：[1]西安科技大学,西安710054

出　　处：《铁道工程学报》2013年第9期92-98,共7页Journal of Railway Engineering Society

基　　金：陕西省教育厅自然科学专项资助(2010JK667)

摘　　要：研究目的:以北京地区某复杂条件下暗挖地铁车站工程为依托,通过FLAC模拟预测的地表及桥桩沉降规律与现场实测数据的对比分析,得到PBA法修建地铁车站诱发的地表及桥桩的沉降规律,为暗挖地铁车站的信息化施工提供技术支撑。研究结论:(1)FLAC模拟表明,随着导洞的开挖,地表产生的沉降量逐渐增加,由桥上部荷载及自重对地表土层产生的影响,在开挖初期对地表沉降起着主要作用,沉降槽曲线逐渐由双峰变为单峰,最大地表沉降位于导洞开挖的中心线位置,预测的最大沉降值和现场实测值分别为24.75 mm和25.51 mm,桥桩最大沉降量预测值和实测值分别为5.11 mm和5.89 mm,两者基本一致;(2)暗挖地铁车站PBA法施工方案和现场监测方案设计合理,地表及桥桩的沉降满足规范要求;(3)该研究成果可为地质条件差、断面大的类似暗挖地铁车站提供施工和监测参考。Research purposes： Based on an underground metro station project in Beijing with complicated conditions, the comparison of the settlement regulations of the ground surface and bridge pier obtained by conducting the FLAC simulation prediction with the actual measured data was made to know the settlement regulations of the ground surface and bridge pier induced by the metro station construction with PBA method for providing the technical support for the information construction of underground metro station. Research conclusions： （ 1 ） The FLAC simulation showed that with the excavation of the pilot tunnel, the settlement of the ground surface gradually increased. The curve of the settlement groove gradually changed from double peaks to single peak due to the influence of the load of the upper bridge and the dead weight of the bridge on the surface soil with playing a major role in the surface settlement at the beginning of the excavation. The maximum surface settlement happened in the center position of pilot tunnel excavation. The maximum predicted value of the ground settlement was 24.75 mm and the measured value was 25.51 mm. The maximum predicted value of the bridge pier settlement was 5.11 mm and the measured value was 5.89 mm. Both were basically the same. （2） The result showed that the PBA construction scheme for metro station and the in - site monitoring scheme were reasonable in design, and the deformations of the ground surface and pier met the specification requirements. （3） This research result could provide the reference to construction and monitoring of the large - section metro station in the area with poor geological conditions.

关 键 词：暗挖地铁车站 PBA法 地表 桥桩 沉降 FLAC数值模拟 现场监测 

分 类 号：U231.4[交通运输工程—道路与铁道工程]