岩石迭代损伤与膨胀演化规律研究

Study on iterated damage and swelling evolution of rock

本文基于应变等效性假说的变形模量衰减损伤理论,通过分析岩石压缩变形过程中迭代的演化特征,得出了岩石损伤演化规律,并从迭代角度建立了模拟该损伤演化规律的方法,在此基础上推导了一种新的岩石损伤本构模型,进而分析了损伤演化过程的混沌特征;基于扫描电镜观察到的软岩微观结构,建立统计力学模型,分析了软岩膨胀的物理化学效应。研究结果表明:基于微缺陷迭代生长角度提出的损伤演化模型能够实现对岩石压缩变形全过程损伤演化规律统一、完整的描述,理论曲线与试验数据具有很好的一致性;软岩膨胀的物理化学效应既可能引起有限次物理相变,也可能引起无穷次物理相变,甚至使软岩进入异常复杂的玻璃态转变状态,这同软岩膨胀机理的复杂性高度契合。

The law of rock damage evolution is concluded by analyzing iterative evolution characteristics in the process of rock compression deformation using the strain equivalence hypothesis.The damage evolution process of chaotic characteristics is analyzed using the iteration method after a rock damage constitutive model is developed.A statistical mechanical model is developed based on the microstructure of a scanning electron microscope to analyze the physical and chemical effects of soft rock swelling.The results show that the damage evolution model based on the micro-defect iterative can describe the rock compression deformation damage evolution law,and the proposed strain softening constitutive model agrees well with the experimental data.The physicochemical effects of soft rock swelling can cause finite or infinite physical phase transitions,as well as cause the soft rock mass to enter an unusually complex glassy transition state,which is highly consistent with the complexity of the soft rock swelling mechanism.