砂卵石地层盾构隧道联络通道冻结法盐水降温计划研究  

Study of Brine Cooling Plan for Freezing Method of Shield Tunnel Connecting Gallery in Sand and Cobble Stratum

作　　者：张琛 王士民[1] 彭小雨 王亚[1] ZHANG Chen;WANG Shimin;PENG Xiaoyu;WANG Ya(China Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,Sichuan,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031

出　　处：《隧道建设（中英文）》2022年第S02期251-260,共10页Tunnel Construction

基　　金：国家自然科学基金项目(52178398)。

摘　　要：为探究盾构隧道联络通道冻结加固工程中盐水降温计划对冻结进程的影响规律,依托洛阳地铁1号联络通道冻结加固工程,分别从改变起始盐水温度和盐水降温梯度2个角度,设置2种盐水降温方案,利用ANSYS有限元软件对2种方案下的地层冻结加固进程进行模拟。通过分析设计冻结加固范围内的地层温度场分布的时空特性、等温圈分布形态以及冻结壁厚度等,得到如下结论:1)在10~-20℃范围降低盐水起始温度、在起始盐水温度和终止盐水温度不变的情况下增大降温梯度2种方式都可以加快冻结进程;2)保持终止盐水温度相同的情况下,改变起始盐水温度或改变降温梯度,在冻结相同时间后,不影响最终的冻结帷幕形态;3)综合考虑经济效益和冻结效果,建议设置起始盐水温度为0℃,终止盐水温度为-30℃,且在最大日降温梯度占降温总量的30%,同时设定第16天达到并维持终止冻结温度。In order to investigate the influence law of brine cooling plan on freezing process,the Luoyang metro No.1connecting gallery freezing reinforcement project is studied.Two brine cooling plans are set by changing the starting brine temperature and the brine cooling gradient respectively,and ANSYS finite element software is used to simulate the freezing and strengthening process of the stratum under the plans.By analyzing the spatial and temporal distribution characteristics of stratigraphic temperature field,the distribution pattern of isothermal circle,and the thickness of freezing wall within the designed freezing and consolidation area,the following conclusions are obtained:(1)Reducing the starting brine temperature in the range of 10~20℃and increasing the cooling gradient while keeping the starting brine temperature and terminating brine temperature unchanged can accelerate the freezing process in both ways;(2)While keeping the terminating brine temperature the same but changing the starting brine or the cooling gradient,the final freezing curtain form is unaffected after freezing for the same period of time;(3)Considering the economic benefits and freezing effect,it is recommended to set the starting brine temperature at 0℃and the ending brine temperature at-30℃,and to set the maximum daily cooling gradient at 30%of the total cooling,while setting the 16th day to reach and maintain the ending freezing temperature.

关 键 词：盾构隧道 联络通道 冻结法 盐水降温计划 冻结进程 冻结帷幕 温度场 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]