岩质地层暗挖车站施工设计关键技术研究

Key Technology for the Construction Design of Mining Metro Station in Rock Strata

针对岩质地层条件下暗挖法地铁车站设计中遇到的隧洞开挖方式、衬砌支护参数,以及主体结构与风道结构的接口设计方案等几项关键技术,运用数值计算与理论分析相结合的手段,并利用现场实测数据进行对比分析,研究表明:双侧壁导坑法施工工艺是安全可行的,初期支护结构可以按破损阶段法进行验算,超前支护与封闭钢架相结合的方式能形成完整的支护体系,并能确保车站主体结构与风道结构接口处的步步封闭与施工安全。通过分析还发现,围岩应力和位移变化较大的区域主要集中在隧道拱顶与拱脚附近,施工过程中的安全系数呈现先减小后增大的变化趋势。研究结论对类似地层条件下的暗挖法地铁车站提供借鉴与参考。

Focused on the mining method,the parameters of primary support,and the design method for the interface of metro station and air duct structure,what are encountered during the design of mining the metro station in rock strata. Through the combination of numerical method and theoretical analysis,and comparison with field measured data,we know that double-side-wall heading method is safe and feasible,the design method based on plastic stage can be used for the checking of primary support structure,and the combination of support in advance with closed steel frame can ensure the safety of the interface of metro station and air duct structure. Through analysis,the changes of displacement and stress are focused around vault and arch springer,and the safety factor during construction decreass firstly then increases. The study can offer a reference for the similar project in the future.