Abstract:Research purposes: In the process of shield construction of metro,the end area is the place where the shield machine departs and arrives and where the accidents easily happen. The reinforcement of the end area is crucial to the departure and arrival safety of the shield machine . In the loose unstable alluvial layer,the water - containing rock layer with the pore development,the slush layer,the soft mud stone layer,the saturated layer and the layer with high water head,how to well use the freezing method and conducting the reinforcement monitoring are the key elements to guarantee successful construction of shield tunnel.
Research conclusions: The difference between reinforcing the soil on the ends with freezing method and reinforcing the ordinary foundation is that the former has the requirement of the freezing temperature. Only when the freezing temperature is guaranteed can the soil strength on the ends be guaranteed and the risks of sand and water bursting be effectively controlled. In order to avoid the appearance of accident,the relative measures should be taken such as using small propulsive force,slow cutting and avoiding the freezing of the cutter head when the shield machine passes through the soil on ends.
Yang Ping, Yuan Yunhui, She Caigao, etc. Temperature Study on Artificial Soil Freezing Reinforcement for Shield Entry in Ji Tsing - men Station of Nanjing Metro [J]. Journal of PLA University of Science and Technology ( Natural Science Edition) ,2009( 6) : 591 - 596.
Li Dayong,Wang Hui,Wang Teng. Analysis of Soil Reinforcement for the Starting and Arriving of Shield Machine in Metro Construction[J]. Journal of Railway Engineering Society,2006( 1) : 87 - 90.
Wang,Xiaobin,Yang Ping,Zhang,Ting,etc. 3 - D Finite Element Analysis of Melting Temperature Field in Shield Tunneling Horizontal Freezing Reinforcing Engineering[J]. Journal of PLA University of Science and Technology ( Natural Science Edition) ,2009 ( 6 ) : 586 - 590.
[4] GB 50299—1999,地下铁道工程施工及验收规范[S].
GB 50299—1999,Code for Construction and Acceptance of Metro Engineering[S].
[5] DG/TJ 08—902—2006,旁通道冻结法技术规程[S].
DG /TJ 08—902—2006,Technical Code for Bypass Freeing Method[S].
Cao,Honglin. Thawing Settlement Control of Subway Tunnel Construction by Arti6ciaI Ground Freezing[J]. Chinese Journal of Underground Space and Engineering,2010( 2) : 387 - 390.
Bao Yongliang, Zheng Qizhen, Tang Jianzhong. Monitoring Analysis of Construction for Connecting Aisle in Metro Tunnel with Freezing Method [J]. Journal of Railway Engineering Society,2009 ( 3) : 93 -95.