基于新型损伤定义的岩石损伤统计本构模型探讨

针对几何损伤理论中损伤定义的局限性与不足，对岩石损伤定义进行了改进；在此基础上，将在应力作用下的岩石材料抽象为破坏与未破坏两部分，并根据这两部分不同的受力情况，建立出新型损伤模型；其次，利用统计损伤理论，建立出岩石统计损伤演化方程，进而建立起基于特定围压下的岩石损伤统计本构模型；然后，通过探讨模型参数与围压的经验关系，对模型进行合理修正，从而建立了反映不同围压条件下的岩石损伤统计本构模型，并通过探讨模型参数的物理意义，初步建立了反映岩石软化与硬化特性相互转化的临界物理力学参数的确定方法。该模型能够反映岩石软化与硬化特性相互转化的特征，与试验结果进行比较分析表明，该模型与实测结果吻合良好。

Study on statistical damage constitutive model of rock based on new definition of damage

Firstly, the definition of damage for rock was improved according to some insufficiency or disadvantages of the definition of damage in geometric damage theory. On basis of it, rock material under stress was abstracted into two parts for failed and un-failed material; and then a new damage model had been created according to differences of two parts under force. Secondly, a statistical damage evolution equation was established by making use of statistical damage theory; and furthermore a statistical damage constitutive model of rock under a specific confining pressure has been set up. Thirdly, the model has been modified rationally by discussing the empirical relation between parameters of the model and confining pressure of rock; and then a statistical damage constitutive model applying to the condition of different confining pressures has been founded. At last, with studying physical signification of the parameters of the model, a way to find critical physical and mechanical parameters reflecting conversion between hardening and softening mutually is initially developed. It could also reflect characteristic about conversion between hardening and softening mutually; and its rationality has been shown compared with its test.