砂卵石地层中PBA工法暗挖车站监控量测分析

北京地铁7号线达官营站主体结构为地下两层直墙三连拱结构,采用PBA工法施工。车站跨度大,PBA工法施工转换多,且车站位于砂卵石地层中,周边情况复杂,施工难度大,风险高。结合工程实例进行剖析,通过监控量测技术分析,证明通过详细的环境调查及精心的施工部署,复杂条件下地铁暗挖车站PBA工法施工的可行性,并为今后类似工程施工提供参考借鉴。

Monitoring and Measurement of the Application of PBA(pile-beam-arc)Method in Sand Cobble Stratum

Beijing subway No. 7 line Daguanying station will be of two layers underground major structure with straight wall and three-connected-arch structure built by PBA construction method. Due to the reason that the Daguanying station is of large span, PBA construction method adopted will be of more supporting structural connections, station locates in sand cobble stratum and the construction condition around is complex, so the construction should be difficult and in high risk. Combined by analysis of project example and monitoring measurement, this paper demonstrates that PBA construction method is available to excavate underground station in complex condition by means of making detailed environmental investigation and careful construction arrangement. It will provide reference for similar project in the future.