含相变低温岩体水热耦合模型研究

 根据冻融循环条件下岩体水分运动和热量迁移的基本规律，基于连续介质力学、热力学以及分凝势理论，建立低温岩体温度场和渗流场耦合控制方程，该耦合方程不仅考虑了热传导、相变潜热和渗流速度对温度分布的影响，而且分析了由分凝势引起的孔隙水流动对渗流速度以及渗透压力分布的影响，实现了温度场和渗流场的双向全耦合。并将研究成果与M. Smith等的模型试验和现场试验进行对比分析，结果表明，所建立的耦合控制方程计算结果与实测结果吻合较好。在此基础上，应用此耦合模型数值仿真寒区隧道，对隧道温度场分布规律和冻融圈大小进行分析，该计算结果能为寒区隧道的设计和施工提供一定的参考。

A COUPLED HYDRO-THERMAL MODEL FOR LOW TEMPERATURE ROCK INCLUDING PHASE CHANGE

According to the basic laws of water movement and heat migration about rock mass under the freezing- thawing cycle condition，based on the theory of continuum mechanics，thermodynamics and segregation potential，the coupled equations of seepage field and temperature field are established. This model can not only consider the influence of thermal conduction，latent heat and seepage velocity on the distribution of temperature，but also analyze the effect of water flow induced by segregation potential on the seepage velocity and seepage pressure. To verify the reliability and rationality of the equations，the comparison is done by using the same conditions between the model test which was done by M. Smith and the finite element analysis using this coupled mathematical model. Then the model is applied to a cold regional tunnel，and the distribution of temperature and active ring of permafrost are obtained. The results can give some references for design and construction of tunnel in cold regions.