中文摘要：

兰州市轨道交通一号线东岗站后配线段黄土地层大跨区间隧道采用双侧壁导坑法施工,根据不同断面的监测数据对比分析初期支护围岩压力和格栅拱架钢筋应力的分布规律。结果表明：格栅拱架支护作用明显,钢筋应力最大值为108.27 MPa,位于隧道拱腰处,满足设计要求;测试断面拱腰和拱肩处围岩压力、钢筋应力相对较大,施工过程中应加强变形监测和控制;初期支护局部变形较大时采用临时钢支撑辅助加固效果明显;整个断面格栅拱架钢筋应力分布不均匀,格栅拱架的分段架设与连接须牢固,以提高结构的整体性;仰拱施作完毕7 d后,整个断面围岩压力和格栅拱架钢筋应力趋于稳定。

英文摘要：

The large span running tunnel in loess stratum of Donggang Station＇s Rear Wiring Section,part of Lanzhou Rail transit Line 1,was built using double side drift method.The distributions of the pressure of surrounding rock of initial support and the steel stress of the lattice arch were analyzed with the monitoring data at different sections.The results show that the supporting effect of the lattice arch is significant.The maximum steel stress is 108.27 MPa,located at the tunnel arch waist,meeting the design requirements.The surrounding rock pressure and steel stress at the arch waist and shoulder of the tested section are relatively large,suggesting more deformation monitoring and controlling during construction.A temporary steel support is suggested for reinforcement if the local deformation of initial support is large.The steel stress distribution of the entire lattice arch is not uniform.The segments of the lattice arch shall be tied with joints tightly to improve the structural integrity.Seven days after the inverted arch construction was completed,the surrounding rock pressure and the steel stress of the lattice arch at the entire section tend to be stable.