人工冻土温度场模型试验及冻土导热系数反分析

Model Test of Artificial Frozen Soil Temperature Field and Back Analysis of Thermal Conductivity of Frozen Soil

掌握人工冻土温度场的相关物理力学性质对冻结法施工意义重大,导热系数是计算人工冻土温度场的关键参数。采用人工冻土冻结试验平台进行人工冻土温度场试验,在模型土体的不同深度、不同平面位置布置热电耦测量温度的实时发展规律。通过数值法模拟人工冻土冻结温度场模型试验,对比分析不同点温度监测值和模拟值的关系,再以反分析方法为基础,利用最小二乘法准则将数值计算得到的测温点计算温度与实测温度进行对比分析,然后在准则函数计算范围内,用数值逼近原理,得到最优导热系数。最后,将最优导热系数的模拟温度和实测温度进行对比,验证得到的等效导热系数具有准确性。

Mastering the development law of artificial frozen soil temperature field is of great significance to the safety evaluation of artificial freezing method.The thermal conductivity is the key parameter for calculating the temperature field of artificial frozen soil.The artificial frozen soil test platform was used to conduct the temperature field test of the artificial frozen soil.The real-time development rule of thermoelectric coupling measurement temperature was arranged at different depth and plane positions of the model soil.The numerical simulation was used to simulate the freezing temperature field model test of artificial frozen soil,analysis of the relationship value and simulation value difference temperature monitoring.On the basis of back analysis method,by using the least square criterion,the calculated temperature and the measured temperature of the temperature measured by numerical calculation were compared and analyzed.Within the scope of the criterion function calculation,numerical approximation principlewas used to obtain the optimal coefficient of thermal conductivity.The simulated temperature of the optimal thermal conductivity was compared with the measured temperature.The results verify the accuracy of the equivalent thermal conductivity obtained.