【摘要】 针对现有岩石损伤模型的局限性与不足,将应力作用下的岩石抽象为空隙、损伤与未损伤材料三部分,以空隙率反映岩石体积或空隙的变化,以损伤变量或损伤因子反映岩石力学性态的改变程度,通过对各部分材料的微观受力及其与宏观应力和应变的关系进行分析,建立了可反映岩石变形过程中体积或空隙变化特性的新型岩石损伤模型;从岩石微元强度合理度量方法研究入手,引进统计损伤理论,建立了可考虑损伤阀值影响的岩石统计损伤演化模型,进而建立了能模拟应变软硬化全过程的岩石统计损伤本构模型,并提出了参数确定方法。该模型不仅能反映岩石应变软硬化特性,而且能反映岩石变形的初期压密和后期扩容的特性。通过实例分析与讨论,表明模型合理与可行。更多还原

【Abstract】 Aiming at the limitations and deficiencies of the current rock damage models,firstly,the rock under stress is divided into three parts abstractly: voids,damaged and undamaged material.The voids ratio is employed to describe rock’s change of the volume and the voids;and the damage variable or damage coefficient is used to reflect the conversion degree of mechanical property and state of rock.Then,a new damage model for rock is proposed according to analysis of microcosmic stress and discussion on the relationship between rock’s macrocosmic stresses and strains.Secondly,starting with the discussion on the reasonable method to measure the rock microcosmic elemental strength,a statistical damage evolution model for rock to reflect the effect of the damage threshold value is presented by working in statistical damage theory;moreover,a statistical damage constitutive model to simulate the rock full deformation process and its parameters determination method is developed.This model can reflect the properties of not only strain softening or hardening but the volume compression in initial as well as expansion in later.Finally,the analysis and discussion with practical example indicates the rationality and feasibility.更多还原