Study On The Development Regularity Of Multi Row Pipe Freezing Temperature Field Under The Action Of Seepage In Saturated Sand

Artificial freezing method is one of the formation water proof and ground reinforcement methods widely used at home and abroad.Groundwater flow velocity is the key factor to freezing effect and even determines the success or failure of freezing method in freezing construction process.Combined with multi row pipe adopted frequently in municipal construction,this paper chooses the saturated seepage ground of sands as the object of study.Study on the development regularity of the freezing temperature field under the action of seepage was conducted by the methods of numerical calculation and physical experiment.Firstly,the numerical simulation of the freezing temperature field has been carried out,and the finite element model with structure analysis soft Comsol was built.The numerical simulation of the Thermal-Hydro coupling field in porous media was achieved by using the user-defined PDES in Comsol.The development regularity of the freezing temperature field and seepage field under the action of seepage has been analyzed by typical factor experiment.The relationships between the frozen wall thickness,average temperature,circle-crossing time and the groundwater flow velocity,spacing of frozen pipe,row spacing of frozen pipe,row number of frozen pipe,direction of the seepage water were analyzed by the single factor experiments.The influence and significance of various factors on the seepage-temperature field were analyzed by orthogonal experiment.Secondly,according to similar criteria,physical simulation experimental study has been carried out,and the temperature changing conditions of the measuring point on the feature face and circle-crossing time were achieved.Hereby,the paper analyzed the changing regularity of the frozen wall thickness.Finally,the paper compared the results of freezing temperature field under the action of seepage obtained by numerical simulation research and experiment simulation research.And got the conclusion that the laws of temperature field obtained by the two methods were similar,but the data of experiment simulation research were slightly larger than numerical simulation research,and the reasons were stated.The contents of this paper will provide some references on the design and construction of artificial freezing method applied in seepage ground of sands.