考虑裂纹闭合效应的岩石损伤力学模型及耗散能量分析  

A Rock Damage Mechanics Model and Analysis on Damage Energy Dissipation in Consideration of Crack Closure Effect

作　　者：温韬[1] 唐辉明[1] 刘佑荣[1] 王康[1] 易贤龙[1] 谭钦文[1] 

机构地区：[1]中国地质大学(武汉)工程学院,武汉430074

出　　处：《长江科学院院报》2016年第5期69-75,共7页Journal of Changjiang River Scientific Research Institute

摘　　要：针对现有岩石损伤力学模型的局限性,考虑裂纹闭合效应,并引入统计损伤理论,同时提出分布参数确定的方法,建立新型岩石损伤力学模型。该模型更加符合岩石的变形破坏规律,还可以反映岩石的残余强度和延性特征,应用范围更广;与试验结果及前人成果对比,表明模型更为合理可行。不同围压下岩样的损伤变量演化曲线都遵循S型曲线,并可以依据S型曲线对岩石的变形破坏阶段进行划分。裂纹闭合系数(h)对损伤耗能率有较大影响,随着h的减小,损伤耗能率增大,当h达到一定值,岩石破坏阶段对应的损伤耗能率陡增。因此,岩石的变形破坏不仅与其应力状态有关,还与岩石的损伤演化积累以及裂纹闭合效应有关。In view of the insufficiency of the present rock tutive model of rock damage damage mechanics models, we propose a statistical consti- considering the crack closure effect by introducing the statistical damage theory. The model is more consistent with the deformation and failure regularity of rock, and reflects the residual strength and ductility, hence having a wide range of application. The model is proved to be rational and feasible through compar- ison with the existing research results and measured data. The curves of damage variable under different confining pressures conform with the ＂S＂ shape, which can be divided into different phases according to the deformation fail- ure stages. Crack closure coefficient （h） has great influence on the damage energy dissipation rate. With the de- crease of h , damage energy dissipation rate increases ; when the value of h reaches a certain value, the ergy dissipation rate rises sharply. also involves the accumulation of damage en- Therefore, the deformation failure of rock is not only related with stress state, but damage evolution and crack closure effect.

关 键 词：岩石力学 损伤 裂纹闭合系数 损伤耗能率 微元强度 

分 类 号：TU45[建筑科学—岩土工程]