冻结温度下岩体THM完全耦合的理论初步分析

在冻结温度下，岩体受内部孔隙水、结构面及温度等的影响，其物理力学性质将发生深刻的变化，因而，一般热力学理论已经难以解释该问题。从不可逆过程热力学和连续介质力学理论出发，在若干合理的假定条件下，推导了冻结温度下岩体的质量守恒方程、平衡方程及能量守恒方程的最终表示形式；研究了岩体在冻结温度下冰与岩石的膨胀耦合关系，并建立了相应的耦合膨胀系数的表达式。为研究寒区工程围岩温度场、渗流场及应力场的分布规律及变形机理提供了新的理论依据。

THEORETICAL ANALYSIS ON FULL THERMO-HYDRO-MECHANICAL COUPLING FOR ROCKS UNDER FREEZING TEMPERATURE

The mechanical properties of rock may change dramatically due to porous water,discontinuity and sub-zero temperature. The traditional principles of thermodynamics, however, can not solve this problem or explain the phenomena. Based on the principles of irreversible thermodynamics and the mechanics of continuous medium, the continuity equation, equilibrium equation and energy conservation equation can be coupled via some simplified assumptions. Moreover,the relationship between rock and ice in a frozen rockmass is studied and a coupled coefficient of expansion is proposed. It gives a new theoretical basis for studying temperature, seepage and stress distribution in rock mass in cold regions.