水平冻结法在无锡地铁站盾构始发与接收洞门加固中的应用

Application of Horizontal Freezing Technique in Shield Departure and Reception Portal Reinforcement of Wuxi Metro Station

无锡地铁4号线市民中心站—吴都路站区间的市民中心站地处软黏土层,洞门钻孔取芯时存在喷涌情况,且地下管线复杂,因此采用水平冻结法对盾构进出洞门进行加固。以盾构始发与接收水平冻结施工为例,介绍了冻结设计方案、盾构始发与接收过程以及实际应用效果。结果表明,水平冻结设计方案合理,盾构始发与接收技术措施可靠,冻结加固区总去回路盐水温度、内外圈回路盐水温度和各测温孔中测温点温度均存在阶段性变化特征。采用水平冻结法,盾构在市民中心站成功实现始发与接收。

The Civic Center station at interval between Civic Center station and Wudu Road station of Wuxi Metro Line 4 is located in soft clay layer.The outpouring phenomenon exists in the process of portal drilling for core,with the complexity of underground pipelines,horizontal freezing method is adopted to reinforce the portal of shield departure and reception.Taking the horizontal freezing construction of shield departure and reception as an example,the freezing design scheme,the departure and reception process of shield and actual application result are introduced.The results show that the horizontal freezing design scheme is feasible,and the technical measures for shield departure and reception are reliable.Characteristics of phased change exist in aspects of the total incoming and outgoing road saline temperature,the outgoing road saline temperature between the inner and outer ring,and measuring point temperature of each thermometer hole in frozen zone.With horizontal freezing method,the departure and reception of shield is successfully implemented at Civic Center station.