In view of the insufficiency of the present rock damage mechanics models, we propose a statistical constitutive model of rock damage 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 comparison 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 failure stages. Crack closure coefficient (h) has great influence on the damage energy dissipation rate. With the decrease of h , damage energy dissipation rate increases; when the value of h reaches a certain value, the damage energy dissipation rate rises sharply. Therefore, the deformation failure of rock is not only related with stress state, but also involves the accumulation of damage evolution and crack closure effect.
Key words
rock mechanics /
damage /
crack closure effect /
damage energy dissipation rate /
micro element strength
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1]KACHNOV M. Effective Elastic Properties of Cracked Solids: Critical Review of Some Basic Concepts [J]. Applied Mechanics Reviews, 1992, 45(8):304-335.
[2] KACHANOV M, TSUKROV I, SHAFIRO B. Effective Modulus of Solids with Cavities of Various Shapes[J]. Applied Mechanics Review, 1994, 47(Sup.1): 151-174.
[3] KRAJCINOVIC D. The Continuous Damage Theory of Brittle Materials[J]. Journal of Applied Mechanics, 1981,48(8) : 809-822.
[4] KRAJCINOVIC D. Statistical Aspects of the Continuous Damage Theory[J]. International Journal of Solids and Structures, 1982, 18(7): 551-562.
[5] KRAJCINOVIC D,SILVA M A G. Statistical Aspects of the Continuous Damage Theory[J]. International Journal of Solids and Structures, 1982, 18(7): 551-562.
[6] 谢和平.岩石、混凝土损伤力学[M].江苏徐州:中国矿业大学出版社,1990.
[7] 曹文贵,赵明华,刘成学.基于统计损伤理论的德鲁克-普拉格岩石强度准则的修正[J].水利学报,2004,(9):18-23.
[8] 曹文贵,莫 瑞,李 翔.基于正态分布的岩石软硬化损伤统计本构模型及其参数确定方法探讨[J].岩土工程学报, 2007,29(5):671-675.
[9] 曹文贵,李 翔,刘 峰.裂隙化岩体应变软化损伤本构模型探讨[J].岩石力学与工程学报,2007,26(12):2488-2494.
[10]曹文贵.岩石损伤软化统计本构模型之研究[J]. 岩石力学与工程学报, 1998,17(6):628-633.
[11]温 韬,唐辉明,刘佑荣,等.影响因子修正的新型岩石损伤统计本构模型[J].中国矿业大学学报(自然科学版),2016,45(1):142-150.
[12]杨明辉,赵明华,曹文贵.岩石损伤软化统计本构模型参数的确定方法[J].水利学报,2005,36(3):345-349.
[13]徐卫亚,韦立德.岩石损伤统计本构模型的研究[J].岩石力学与工程学报,2002,21(6):787-791.
[14]杨圣奇,徐卫亚,韦立德,等.单轴压缩下岩石损伤统计本构模型与试验研究[J].河海大学学报(自然科学版),2004,32(2):200-203.
[15]李兆霞.损伤力学及其应用[M].北京:科学出版社,2002:16-19.
[16]尹光志, 张东明.脆性煤岩损伤模型及冲击地压损伤能量指数[J].重庆大学学报:自然科学版, 2002,25(9):75-78.
[17]温 韬,刘佑荣,胡 政. 高应力区砂岩加卸载条件下能量变化规律及损伤分析[J]. 地质科技情报,2015,34(2):200-206.
[18]杨光松.损伤力学与复合材料损伤[M].北京:国防工业出版社,1995.
[19]让·勒墨特黑,余天庆.预估结构中的塑性破坏或蠕变疲劳破坏的损伤模型[J].固体力学学报,1981,(4):512-525.
PDF(1229 KB)
