裂隙延展性统计分布离散性对岩体块体化程度REV的影响
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摘要
表征单元体(REV)的存在是应用连续介质力学方法对岩体进行研究的前提,REV可以从岩体块体化程度的角度进行研究,裂隙大小及其统计分布是影响岩体块体化程度REV的重要因素。本文利用课题组自主研发的General Block软件,建立更一般化实际化的模型,研究裂隙延展性统计分布的离散程度对岩体块体化程度REV的影响。分析时选取了最常用的裂隙延展性统计分布形式:正态分布。由于所建立的岩体结构模型是随机的,需要对每个随机裂隙模型进行多次实现。为节省计算量,当研究范围比较小时,对每种结构的每个研究范围进行9次随机实现。当研究范围足够大,达到REV大小的时候进行100次随机实现。为确定离散程度对表征单元体的影响,本文针对5个不同标准差进行了模拟分析(共建立了1 005个裂隙模型,分别进行了块体识别并计算其块体化程度B)。结果表明,裂隙延展性服从正态分布的情况下,如果其平均值一定,岩体的块体化程度随着统计分布离散程度的增加略有上升,裂隙岩体的REV值基本上由裂隙延展性统计平均值决定。
The existence of representative elementary volume( REV) is the premise of using the continuousmedia method to study rock mass,and it can be studied from the view of blockiness. The size and statistical distribution of the fractures are the important factors in the blockiness REV of fractured rock masses. In this paper more generalized models are built to examine the influence of statistical distribution dispersion in the fracture size on the Blockiness REV of fractured rock masses by using the General Block software,which was developed by our research group. The most common statistical distribution of the fracture size,the normal distribution,is used. For each model, multiple realizations are carried out to reduce the effects of randomness. To improve the efficiency of computation,9 random realizations are performed when the model domains are small. When the model domain sizes reach the REV volume,100 random realizations are carried out. Five different standard deviations are considered in the simulation analysis to study the influence of statistical distribution dispersion in fracture size on the blockiness REV( 1 005 fracture models are established,and rock blocks in each models are identified to calculate the blockiness). The results indicate that if the distribution of fracture size is normal,the REV is controlled by the mean value of the fracture size,and the blockiness increases slightly with the distribution dispersion in the fracture size.
The existence of representative elementary volume( REV) is the premise of using the continuousmedia method to study rock mass,and it can be studied from the view of blockiness. The size and statistical distribution of the fractures are the important factors in the blockiness REV of fractured rock masses. In this paper more generalized models are built to examine the influence of statistical distribution dispersion in the fracture size on the Blockiness REV of fractured rock masses by using the General Block software,which was developed by our research group. The most common statistical distribution of the fracture size,the normal distribution,is used. For each model, multiple realizations are carried out to reduce the effects of randomness. To improve the efficiency of computation,9 random realizations are performed when the model domains are small. When the model domain sizes reach the REV volume,100 random realizations are carried out. Five different standard deviations are considered in the simulation analysis to study the influence of statistical distribution dispersion in fracture size on the blockiness REV( 1 005 fracture models are established,and rock blocks in each models are identified to calculate the blockiness). The results indicate that if the distribution of fracture size is normal,the REV is controlled by the mean value of the fracture size,and the blockiness increases slightly with the distribution dispersion in the fracture size.
引文
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[2] LONG J C S. Porous media equivalents for networks of discontinuous fractures[J]. Water Resources Research,1982,18(3):645-658.
[3] WANG M,KULATILAKE P H S. Estimation of REV size and three-dimensional hydraulic conductivity tensor for a fractured rock mass through a single well packer test and discrete fracture fluid flow modeling[J]. International Journal of Rock Mechanics and Mining Sciences,2002,39(7):887-904.
[4]张贵科,徐卫亚.裂隙网络模拟与REV尺度研究[J].岩土力学,2008,29(6):1675-1680.[ZHANG G K,XU W Y. Analysis of joint network simulation method and REV scale[J]. Rock and Soil Mechanics, 2008, 29(6):1675-1680.(in Chinese)]
[5]安玉华,王清.基于三维裂隙网络的裂隙岩体表征单元体研究[J].岩土力学,2012,33(12):3775-3780.[AN Y H,WANG Q. Analysis of representative element volume size based on 3D fracture network[J]. Rock and Soil Mechanics,2012,33(12):3775-3780.(in Chinese)]
[6] XIA L,ZHENG Y H,YU Q C. Estimation of the REV size for blockiness of fractured rock masses[J].Computers and Geotechnics,2016,76:83-92
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[8]陈庆发,韦才寿,牛文静,等.一种基于块体化程度理论的裂隙岩体巷道顶板稳定性分级方法研究[J].岩土力学,2014,35(10):2901-2908.[CHEN Q F,WEI C S,NIU W J,et al. Stability classification of roadway roof in fractured rock mass based on blockiness theory[J]. Rock and Soil Mechanics,2014, 35(10):2901-2908.(in Chinese)]
[9]和大钊,胡斌,姚文敏,等.基于块体化程度和云模型的露天矿边坡稳定性分级评价方法[J].矿冶工程,2017,37(4):6-13.[HE D Z,HU B,YAO W M,et al. Stability grading method for open pit slope based on Blockness and Cloud Model[J].Mining and Metallurgical Engineering,2017,37(4):6-13.(in Chinese)]
[10]王晓明,李会中,王吉亮,等.乌东德水电站右岸地下厂房随机块体特征研究[J].现代地质,2013,27(2):475-481.[WANG X M,LI H Z,WANG J L, et al. Characteristics of stochastic blocks in underground powerhouse on the right bank of Wudongde hydropower station[J]. Geoscience,2013,27(2):475-481.(in Chinese)]
[11] YU Q C, OHNISHI Y, XUE G F, et al. A generalized procedure to identify three-dimensional rock blocks around complex excavations[J].International Journal for Numerical and Analytical Methods in Geomechanics,2009,33(3):355-375
[12] BAECHER G B,LANNEY N A,Einstein H H.Statistical description of rock properties and sampling[C]//The 18thUS Symposium on rock mechanics(USRMS),1977.
[13] ZHANG L,EINSTEIN H H. Estimating the mean trace length of rock discontinuities[J]. Rock Mechanics and Rock Engineering,1998,31(4):217-235.
[14]王晋丽,陈喜,黄远洋,等.岩体裂隙网络随机生成及连通性研究[J].水文地质工程地质,2013,40(2):30-35.[WANG J L,CHEN X,HUANG Y Y, et al. A study of stochastic generation and connectivity of fracture network in rock mass[J].Hydrogeology&Engineering Geology,2013,40(2):30-35.(in Chinese)]
[15] PRIEST S D, HUDSON J A. Estimation of discontinuity spacing and trace length using scanline surveys[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts,1981,18(3):183-197.
[16]张弛,吴剑锋,陈干,等.裂隙网络生成的随机模拟研究[J].水文地质工程地质,2015,42(4):12-17.[ZHANG C,WU J F,CHEN G,et al. A comparative study of stochastic modeling for generating fracture networks[J]. Hydrogeology&Engineering Geology,2015,42(4):12-17.(in Chinese)]
[17]周洪福,宋志,李富,等.鸡公山斜坡岩体裂隙网络模拟及强度参数研究[J].水文地质工程地质,2016,43(3):153-158.[ZHOU H F,SONG Z,LI F,et al. Research on fracture network simulation and parameters of shear strength of the Jigongshan slope[J]. Hydrogeology&Engineering Geology,2016,43(3):153-158.(in Chinese)]
[18]褚宝增,王翠香.概率统计[M].北京:北京大学出版社,2010.[CHU B Z,WANG C X. Probability statistics[M]. Beijing:Peking University Press,2010.(in Chinese)]
[2] LONG J C S. Porous media equivalents for networks of discontinuous fractures[J]. Water Resources Research,1982,18(3):645-658.
[3] WANG M,KULATILAKE P H S. Estimation of REV size and three-dimensional hydraulic conductivity tensor for a fractured rock mass through a single well packer test and discrete fracture fluid flow modeling[J]. International Journal of Rock Mechanics and Mining Sciences,2002,39(7):887-904.
[4]张贵科,徐卫亚.裂隙网络模拟与REV尺度研究[J].岩土力学,2008,29(6):1675-1680.[ZHANG G K,XU W Y. Analysis of joint network simulation method and REV scale[J]. Rock and Soil Mechanics, 2008, 29(6):1675-1680.(in Chinese)]
[5]安玉华,王清.基于三维裂隙网络的裂隙岩体表征单元体研究[J].岩土力学,2012,33(12):3775-3780.[AN Y H,WANG Q. Analysis of representative element volume size based on 3D fracture network[J]. Rock and Soil Mechanics,2012,33(12):3775-3780.(in Chinese)]
[6] XIA L,ZHENG Y H,YU Q C. Estimation of the REV size for blockiness of fractured rock masses[J].Computers and Geotechnics,2016,76:83-92
[7]夏露,李茂华,陈又华,等.三峡工程地下电站厂房岩石块体研究[M].北京:中国水利水电出版社,2015.[XIA L,LI M H,CHEN Y H,et al.Rock blocks in the rock around the underground powerhouse of Three-gorges project[M]. Beijing:China Waterpower Press,2015.(in Chinese)]
[8]陈庆发,韦才寿,牛文静,等.一种基于块体化程度理论的裂隙岩体巷道顶板稳定性分级方法研究[J].岩土力学,2014,35(10):2901-2908.[CHEN Q F,WEI C S,NIU W J,et al. Stability classification of roadway roof in fractured rock mass based on blockiness theory[J]. Rock and Soil Mechanics,2014, 35(10):2901-2908.(in Chinese)]
[9]和大钊,胡斌,姚文敏,等.基于块体化程度和云模型的露天矿边坡稳定性分级评价方法[J].矿冶工程,2017,37(4):6-13.[HE D Z,HU B,YAO W M,et al. Stability grading method for open pit slope based on Blockness and Cloud Model[J].Mining and Metallurgical Engineering,2017,37(4):6-13.(in Chinese)]
[10]王晓明,李会中,王吉亮,等.乌东德水电站右岸地下厂房随机块体特征研究[J].现代地质,2013,27(2):475-481.[WANG X M,LI H Z,WANG J L, et al. Characteristics of stochastic blocks in underground powerhouse on the right bank of Wudongde hydropower station[J]. Geoscience,2013,27(2):475-481.(in Chinese)]
[11] YU Q C, OHNISHI Y, XUE G F, et al. A generalized procedure to identify three-dimensional rock blocks around complex excavations[J].International Journal for Numerical and Analytical Methods in Geomechanics,2009,33(3):355-375
[12] BAECHER G B,LANNEY N A,Einstein H H.Statistical description of rock properties and sampling[C]//The 18thUS Symposium on rock mechanics(USRMS),1977.
[13] ZHANG L,EINSTEIN H H. Estimating the mean trace length of rock discontinuities[J]. Rock Mechanics and Rock Engineering,1998,31(4):217-235.
[14]王晋丽,陈喜,黄远洋,等.岩体裂隙网络随机生成及连通性研究[J].水文地质工程地质,2013,40(2):30-35.[WANG J L,CHEN X,HUANG Y Y, et al. A study of stochastic generation and connectivity of fracture network in rock mass[J].Hydrogeology&Engineering Geology,2013,40(2):30-35.(in Chinese)]
[15] PRIEST S D, HUDSON J A. Estimation of discontinuity spacing and trace length using scanline surveys[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts,1981,18(3):183-197.
[16]张弛,吴剑锋,陈干,等.裂隙网络生成的随机模拟研究[J].水文地质工程地质,2015,42(4):12-17.[ZHANG C,WU J F,CHEN G,et al. A comparative study of stochastic modeling for generating fracture networks[J]. Hydrogeology&Engineering Geology,2015,42(4):12-17.(in Chinese)]
[17]周洪福,宋志,李富,等.鸡公山斜坡岩体裂隙网络模拟及强度参数研究[J].水文地质工程地质,2016,43(3):153-158.[ZHOU H F,SONG Z,LI F,et al. Research on fracture network simulation and parameters of shear strength of the Jigongshan slope[J]. Hydrogeology&Engineering Geology,2016,43(3):153-158.(in Chinese)]
[18]褚宝增,王翠香.概率统计[M].北京:北京大学出版社,2010.[CHU B Z,WANG C X. Probability statistics[M]. Beijing:Peking University Press,2010.(in Chinese)]