Study On The Influence Law Of Frost Heave Effect Of Tunnel Connected Aisle

With the rapid development of urban rail transit,artificial freezing method has become the most reliable and safe construction method in subway tunnel construction.In the process of freezing,the phenomenon of frost heaving of soil mass will have an adverse impact on underground pipelines and surface buildings,which will increase the engineering cost,endanger the engineering safety and cause irreparable losses.In view of this,it is necessary to further study the frost heave phenomenon of the stratum during the freezing process.In this paper,based on the freezing engineering of a connecting passage of Hangzhou Metro,the distribution and development law of the frost heave displacement field in the stratum during the freezing construction of the connecting passage are studied by means of numerical simulation and model test,so as to provide engineering design and safety for the future Provide reference for construction.First of all,numerical simulation is carried out.The distribution and development law of freezing temperature field under typical parameters are studied,and the average thickness and average temperature of the freezing wall are calculated;the displacement generated by the stratum is simulated by the sequential coupling method,and the distribution and development law of the stratum displacement field are obtained;the stress situation of the tunnel lining structure is analyzed.In addition,five single factors,namely tunnel buried depth,angle of freezing pipe,salt water temperature,initial ground temperature and frost heave rate are selected to study the frost heave displacement field of the stratum,and the influence of each factor on the frost heave displacement field of the stratum is studied through orthogonal test.Secondly,carry out physical simulation test.Based on the similarity theory,the engineering case is designed and tested,and the distribution and change rule of temperature field and displacement field and the frost heave pressure data of tunnel are obtained.Finally,the simulation effect is evaluated by comparing the results of numerical simulation and simulation test.Summarize the research results of this paper,and provide suggestions for future research.There are 79 figures and 10 tables as well as 85 references in the paper.