Study On The Development Regularity Of Horizontal And Vertical Bi-directional Freezing Temperature Field In Rescuing TBM Trapped Deeply

Under the background of Gansu Province YinTao Water Delivery first phaseproject7#tunnel rescuing TBM project, the developments and changes law of verticaland horizontal freezing temperature field has been researched in this paper, throughcombined methods of numerical simulation, physical testing and on-sit measurement.Firstly, according to the results of physical simulation experiment, thedevelopments and changes law of bidirectional freezing temperature field has beenresearched through numerical simulation after the adjustment of thermophysicalparameter of soil. In addition, the situation of development and change of temperaturefield and the condition of freezing front of the frozen wall on control section waspredicted under actual working condition. The weak position of bidirectional freezingmodel has been determined. The influence on the law of frozen wall thickness in theweak interface has been researched affected by the following two factors, the spacingof vertical and horizontal freezing pipes and the advanced freezing time. Somefeatures about the frozen wall thickness E and the scale factor k of the averagetemperature and the exine temperature of the freezing tube was found in stabilizedfreezing temperature field.Secondly, according to the preliminary results of numerical simulation, thephysical simulation experiment system was designed reasonably. The experiment hasbeen carried out for grasping the temperature field development and change law.Unanimous conclusion of the experimental and numerical results was obtained.Furthermore, through on-site measurement of freezing temperature field, thetemperature curve has been obtained, the development and change law of the freezingtemperature field in the project has been analyzed.Finally, through comparative analysis on the results of numerical simulation andphysical simulation experiment, numerical simulation and on-sit measurement aboutthe temperature measuring points data and the temperature distribution of the featuresection, aberration on parameter selection as the numerical simulation model assumeshas been analysed, an improved optimization idea about the physical simulationexperiment has been put forward. Through mutual authentication of results obtainedby three kinds of research methods, the development and change law of horizontaland vertical bi-directional freezing temperature field has been received, the circle-crossing time of frozen wall was predicted. The conclusions with significancefor guiding similar projects, are of scientificalness and accuracy.