Study On Influence Of Groundwater Seepage On Freezing Temperature Field Of Contact Channel

In the context of China’s urban subway construction in full swing,the freezing method has been widely used in the construction of subway cross passage,but also faced with a variety of complex engineering environment.There are few cross-passage freezing project examples to consider the role of groundwater seepage,but groundwater activities lead to freeze failure cases are common,so study on the development of freezing temperature field in cross-passage under groundwater seepage is particularly critical for design and safety of engineering.In this paper,the freezing process of the cross-passage in the horizontal seepage field of the thick saturated sand is selected as the object,and numerical simulation and physical simulation test methods will be used in the study of freezing temperature field considering the influence of groundwater seepage in cross-passage.Firstly,through the numerical simulation of the heat-fluid coupling calculation,the analysis of typical parameters is carried out.The development law of the freezing field of the contact channel under the seepage direction of groundwater(along the drilling direction,reverse drilling direction)and variation law of seepage field are obtained,and compare the similarities and differences between the two directions;The influence of groundwater initial flow velocity,freezing pipe horizontal spacing,freezing tube angle and salt water temperature on the freezing temperature field of cross-passage under seepage in different freezing time was obtained by single factor analysis;Through the orthogonal experiment,the effect of each factor on the freezing temperature field of cross-passage under seepage in different freezing time was obtained.Secondly,according to the similarity theory,physical simulation experimental has been carried out to study on freezing temperature field development law of considering the influence of groundwater seepage under experimental conditions in cross-passage,and the experimental results were obtained.Finally,the results of physical simulation test and Numerical simulation will be compared,to investigate the similarities and relevance of the influence of groundwater seepage on temperature field under the two methods.The contents of this thesis will provide some references on strengthening engineering design and researching of the groundwater seepage under cross-passage freezing in the future.