Study On Temperature Field And Variability Of Tunnel Surrounding Rock And Lining In Cold Regions Considering The Condition Of Ventilation

China’s railway construction,in recent years,has extended to northwest cold area,and compared with the conventional tunnel,tunnel in cold regions cause cold injury prone because of tunnel site area location and climate,seriously affect the safety of the main structure of the tunnel,even affect the normal operation of the tunnel.Temperature is one of the main factors of freezing injury occurs in cold regions tunnel,so in order to control the tunnel freezing,you must understand the distribution and variation of temperature field in the alpine region of the tunnel.This paper analyzes the basic theory of the temperature field of tunnel surrounding rock and lining in cold regions,discusses the basic concepts of temperature field,boundary conditions and its classification and factors and relevant theories;Based on the basic principles and methods of fluid mechanics,heat transfer and aerodynamic deduced the model,under consideration ventilation conditions,of temperature field of tunnel surrounding rock in cold regions,and analysis of the numerical simulation of turbulence and heat exchange theory.On this basis,the use of finite element software ANSYS and ANSYS-FLUENT module,through a simple example to validate the feasibility of wind flow field model and numerical simulation of turbulent flow method,and discusses wind speed,air temperature influence law of temperature field of surrounding rock;Under the condition of Kunlun Mountain Tunnel Engineering geological conditions,the use of numerical analysis method to explore insulation measures and the surrounding rock and lining variation of the temperature field under ventilation conditions,respectively,during construction and operation;And further simulation analysis of displacement and stress distribution of surrounding rock and lining of tunnels in cold regions,under the consideration of thermodynamics,and from the perspective of thermodynamics,analyzes the advantages and disadvantages of various insulation measures.Research results show that air temperature,wind speed,respectively by heat conduction,heat exchange are two ways to generate direct and indirect impact on the surrounding rock and lining temperature field,the degree of influence on the temperature field,with the increase of wind speed,wind temperature increase,were exhibits increases first and then inclines to stable value,gradually increasing trend;Setting insulation layer on the tunnel in cold regions can play a significant insulation effect,surface insulation method is superior to double lining insulation method.