Research On The Construction Technology Of Metro Tunnel Passing Through The Existing River In Deep Soft Soil

The construction of subway tunnel through the existing rives has always been a focus of engineering problem. Based on the project of railway lines SI phase SG11A passing through the Beiyang River Metro tunnel in Wenzhou city, this paper carried out the research on the construction technology of metro tunnel passing through the existing river in deep soft soil by means of data collection, scheme research, field measured data analysis, etc. The main research contents and conclusions are as follows:(1) The construction methods used in the metro tunnel passing through the river is briefly introduced, including shield method, open cut method, new Austrian Tunnelling method, cover cut method, immersed tube method, drilling and blasting method, etc., and then the basic method of riverway cofferdam construction is explained.(2) The engineering survey of the railway S1 line crossing through the Beiyang River in Wenzhou deep soft soil area is introduced in great detail, including the construction site engineering geological and hydrological conditions, the cofferdam design situation and the overall construction situation. The overall construction planning, the construction technology and technical measures of the cofferdam, of the retaining structure, and of deep foundation pit excavation, and other measures to prevent leakage, etc., is introduced in detail.(3) The construction risk and safety control measures of the subway tunnel passing through the Beiyang River are analyzed in detail, including the construction organization risk and control measures, the risk of surrounding buildings and pipelines, the resource risk of the main construction equipment, materials, etc., and the deep pit excavation risk in rich water, soft soil zone.(4) The monitoring programs of the subway tunnel crossing the Beiyang River is analyzed in detail, including monitoring contents and methods, and monitoring alarm control standards, etc. The monitoring data during the construction were discussed and analyzed in detail. The results showed that the interval tunnel construction technology used in the subway tunnel passing through the Beiyang River can guarantee for the deep foundation pit in a safe and controlled state.