滨海软土地层人工冻结帷幕形成机理及蠕变损伤耦合本构模型研究

The project uses the method of laboratory tests, full scale freeze model test,field test and finite element numerical analysis to research costal stratum of soft soil deformation mechanism of orizontal freezing curtain, the main contents:(1)Based on laboratory tests , obtain the heat physical laws of nature freeze soft soil, the shear yield surface, volume yield surface, instantaneous loading and unloading guidelines, creep law, creep strength criterion, damage evolution law, damage evolution equation and so on. (2)Obtain the deformation law of artificial frozen soil wall, costal saturated soft clay freezing process thermal coupling mathematical model and thermal coupling unit algorithms developed by full scale model tests. (3) Based on the principles of thermodynamics and continuum medium mechanics, establish artificial freezing of soft soil coupled creep damage constitutive model and develop the constitutive finite element program and parameters inversion program. (4) Based on numerical simulation method of multi scale strong coupling, the proposed constitutive model and thermal coupling subroutine embedded into COMSOL software platform, obtain the whole process of the stratum of large-scale refinement of the costal soft soil layer freeze curtain analysis platform..The research results of the project is the basis for the stratum of artificial freezing curtain of costal soft soil mechanics calculations, providing scientific guidance for permafrost curtain stability analysis and forecasting project. It is of great significance to promote China's municipal freeze law theory and technological progress.

项目采用室内试验、足尺度冻结模型试验、现场实测和有限元数值分析等相结合的方法研究滨海地层软土水平冻结帷幕形成机理，主要研究内容：(1)基于室内试验，获得冻结软土热物理性质规律，剪切屈服面、体积屈服面、瞬时加卸载准则，蠕变规律、蠕变强度准则，损伤演化规律、损伤演化方程等。(2)通过足尺度模型试验，获得人工冻土帷幕形成机理，构建滨海饱和软黏土冻结过程中水热力耦合数学模型，研发水热力耦合单元算法。(3)基于热力学和连续介质力学原理建立人工冻结软土蠕变损伤耦合本构模型，研发本构有限元程序、参数反演程序。(4)基于多尺度强耦合的数值模拟方法，将提出的本构模型及热力耦合子程序嵌入到COMSOL软件平台中，形成大规模全过程精细化的滨海软土地层冻结帷幕分析平台。.项目研究成果是滨海地层软土人工冻结帷幕力学计算的基础，为冻土帷幕稳定性分析与工程预测提供科学指导，对推动我国滨海冻结帷幕设计与施工具有重要意义。

项目采用室内试验、足尺度冻结模型试验、现场实测和有限元数值分析等相结合的方法研究滨海地层软土水平冻结帷幕形成机理，主要研究内容：（1）构建了滨海地层人工冻土本构模型及热物理参数模型，完善和丰富了滨海地层冻土力学。（2）基于滨海饱和软黏土隧道冻结法施工现场实测和室内足尺度模型试验研究，揭示冻结温度场- 水分场- 冻胀应力场演化规律及人工冻结帷幕形成机理。（3）基于多尺度强耦合数值原理，构建滨海地铁隧道人工冻结过程的多尺度全耦合数值分析方法。项目研究成果是滨海地层软土人工冻结帷幕力学计算的基础，为冻土帷幕稳定性分析与工程预测提供科学指导，对推动我国滨海冻结帷幕设计与施工具有重要意义。