中文摘要：

以在建的重庆轨道交通10号线红土地站为工程背景,新建车站采用分离式小净距隧道近距下穿既有车站。通过三维数值分析与现场实测相结合,对既有车站结构的位移响应进行分析。既有结构的竖向位移的位移响应服从双Peck拟合曲线,左、右线隧道开挖引发的竖向位移产生叠加,开挖上台阶和拆除临时支撑为位移控制的关键环节;小净距隧道开挖引起的能量释放被既有车站结构吸收,下穿既有结构所得沉降槽宽度参数值为天然地层条件下的0.924倍;深埋软岩小净距下穿既有结构隧道地层损失率取值范围为0.108%~0.16%;上台阶开挖注意控制拱部中空注浆锚杆的超前加固效果,形成一定范围的承载拱;施作隧道仰拱后方可分段拆除临时中隔壁,拆除范围为6~7m。结果表明,现场实测和数值计算的结果基本吻合。

英文摘要：

The Hongtudi station in progress of Line 10,Chongqing Metro is taken as the project background,whose tunnel is a separate one with small clear spacing and passes close through the existing metro station. The displacement response of the existing metro station is performed by 3D numerical simulation and site measurement. The displacement response of the existing metro station accords with Double-Peck fitting curve,and the superposition of vertical displacement is produced by the double-tunnels＇ excavation. The up-step excavation and temporary support demolition is the key to displacement control. The energy released by the excavation of the small clear spacing tunnel is absorbed by the existing metro station. The parameter of the settlement trough width arising from the crossing of the tunnel is 0. 924 times that of the natural strata and the value range of volume loss due to the crossing is 0. 108% ~ 0. 16%. The up-step excavation can achieve the advanced strengthening effect by controlling the hollowgrouting anchor for the arch,and the load-bearing arch is performed in a dose-dependent manner.The temporary support is demolished after invert construction,and the range of temporary support demolition is less than 6 ~ 7m. The results showthat the results of field measurement and numerical calculation are basically consistent.