深部冻土的广义黏弹塑性损伤本构模型及其应用研究

项目名称： 深部冻土的广义黏弹塑性损伤本构模型及其应用研究

项目编号： No.51204161

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 冶金与矿业学科

项目作者： 杨玉贵

作者单位： 中国矿业大学

项目金额： 26万元

中文摘要： 随着煤炭资源开采不断向深部发展，冻结法凿井穿越表土层厚度不断加大，传统冻土力学理论已不适用于深层冻结壁稳定性评价。为揭示深厚表土冻结壁变形破坏的力学机制，发展和完善深部冻土力学基础理论，本项目拟采用宏、细微观相结合的方法，研究开挖卸荷作用下深部冻土的黏弹塑性损伤本构模型及其工程应用。具体内容包括：开展卸载过程及卸载后蠕变阶段深部冻土的细观损伤CT实时试验，定量研究深部冻土细微观损伤演化与宏观力学行为之间的联系, 建立符合实际的损伤演化方程；研究深部冻土的卸载屈服特征与黏塑性流动轨迹，基于损伤能量等效性假设，构建卸荷条件下冻土的广义黏弹塑性损伤本构关系；采用应力空间变换的方法将本构关系拓展到复杂应力状态，建立深部冻结壁稳定性分析力学模型。通过开展本研究，对于揭示深部冻结壁的变形破坏机理具有重要意义，并为冻结壁的优化设计与支护方式的改进提供理论依据。

中文关键词： 强度准则；广义塑性力学；损伤；本构关系；冻结壁

英文摘要： With the deep mining development of coal resource in China，the depth of topsoil with freezing shaft sinking in deep alluvium increases continuously, the traditional mechanics of frozen soil is no longer suitable for the stability evaluation of deep frozen wall. In order to explore deformation and failure mechanism of deep frozen wall, and to develop the fundamental theory of deep frozen soil, the research on the visco-elastoplastic damage constitutive model and its engineering application for deep frozen soil are carried out by employing the method of macro-meso incorporation in local project. This project is concentrated on the following aspects: the relationship between meso-micro damage evolution characteristic and macro mechanics behavior of frozen soil in unloading processes and creep stage after unloading is established based on the analysis of CT real-time tests, and a realistic damage evolution equation is obtained;the yield characteristic and viscous plasticity flow traces are studied, and a generalized visco-elastoplastic damage constitutive model of frozen soil under the condition of unloading is presented in generalized stress space by introducing the theory of damage mechanics based on the hypothesis of damage energy equivalence;in order to describe the deformation behavior of frozen soil under comp

英文关键词： strength criterion；generalized plastic mechanics；damage；constitutive relationship；frozen soil wall