Abstract：
The subway interval between West Huangcun Station and Liaogongzhuang Station of Beijing Subway Line 6 westward extension project is in sandy cobble stratum and passes through the west fifth ring road. During covered excavation, various technical measures were adopted, such as advance geological detection, deep-hole grouting and advance earth strengthening, setting temporary inverted arch to reduce the excavation section, strictly controlling the grid spacing, initial support fast closing and looping, timely backfill grouting at back of initial support, etc., to reduce the disturbance caused by tunnel excavation on wall rock and to control the settlement of west fifth ring road and retaining wall within the allowable range.
