综合考虑宏微观复合损伤的节理岩体本构模型  

Constitutive model of jointed rock mass by combining macroscopic and microcopic composite damage

作　　者：张吉宏[1,2] 刘红岩[3,4] 

机构地区：[1]长安大学地质工程与测绘学院,陕西西安710064 [2]中国有色金属工业西安勘察设计研究院,陕西西安710064 [3]中国地质大学工程技术学院,北京100083 [4]西藏大学工学院,西藏拉萨850000

出　　处：《煤田地质与勘探》2013年第6期49-52,共4页Coal Geology & Exploration

基　　金：中央高校基本科研业务费专项资金项目(2010ZY45);国家自然科学基金项目(41002113;41162009);教育部科学技术研究重点项目(211175)

摘　　要：针对目前节理岩体损伤本构模型中仅考虑节理等宏观缺陷造成的损伤,而没有考虑岩块中微裂纹等微观损伤的不足,提出了综合考虑宏微观损伤的节理岩体本构模型。其中微观损伤模型采用基于应变强度理论和岩石微元强度服从Weibull分布假定的统计损伤模型,把其应用于被节理切割而成的岩块。而宏观损伤模型主要基于连续介质力学原理,把节理对岩体性质的劣化作为损伤来考虑。在考虑节理传压及传剪系数的基础上,提出了综合考虑宏微观复合损伤的节理岩体本构模型。算例表明宏观节理的存在大大削弱了岩体的强度,降低了其刚度,增大了其柔性。所提出的模型能够较好地反映宏微观两类损伤对岩体应力-应变关系及强度的影响,较为合理。The current study on damage constitutive model of jointed rock mass considers only the macroscopic damage caused by defects such as joints without considering the microscopic damage caused by defects such as micro-crack in rock blocks. Aiming at the above-mentioned shortage, the jointed rock mass constitutive model combining macroscopic and microscopic damage is proposed. The microscopic damage model is a statistical dam- age based on strain strength theory and the strength characteristics of rock micro-unit with Weibull distribution, which is used in rock blocks cut by joints. While the macroscopic damage model is mainly based on continuous media mechanics principle, deterioration of rock mass property caused by joints is regarded as damage. On the basis of considering compression and shear transfer coefficient of the joint, the constitutive model of jointed rock mass by combining macroscopic and microscopic composite damage is proposed. The calculation example indi- cates that existence of the joint greatly weakens the strength of rock mass, reduces its stiffness and enlarges its flexibility. So, the proposed constitutive model can reflect the effect of macroscopic and microscopic damage on rock mass stress-strain relationship and strength, which is rational.

关 键 词：节理岩体 本构模型 宏观损伤 微观损伤 损伤张量 

分 类 号：P642.3[天文地球—工程地质学] TU45[天文地球—地质矿产勘探]