Construction of a 3D equivalent rock random fracture network model and its application in the Lianghekou Hydropower Station
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摘要: 節理的存在對水電高陡巖質邊坡的力學性質有重要影響，如何構建反映三維節理分布特征的等效巖體計算模型，是分析與評價巖體力學特性的關鍵。本文基于損傷力學和統計強度理論，在三維巖石破裂過程分析（RFPA3D）軟件的基礎上，提出了一種計算等效巖體三維隨機節理網絡模型的新方法。首先，基于Baecher模型和Monte-Carlo方法，在RFPA3D軟件中實現了三維隨機離散節理網絡（Discrete fracture network，DFN）模型的重構。然后，利用RFPA3D軟件內嵌DFN模型，賦予節理和巖石不同的力學參數，構建了工程尺度等效巖體三維隨機節理網絡模型，實現了三維隨機節理巖體破裂過程、變形和強度等力學性質的分析。最后，以兩河口水電站左岸邊坡壩址區下游節理巖體為研究對象，驗證了三維隨機DFN模型的準確性，開展了研究區內節理巖體尺寸效應研究，并獲得了研究區內巖體的表征單元體（Representative elementary volume，REV）和等效力學參數。該研究成果為等效巖體力學行為分析提供一種新方法。
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關鍵詞:
- 離散節理網絡模型 /
- 等效巖體三維隨機節理網絡模型 /
- 尺寸效應 /
- 表征單元體 /
- 等效力學參數
Abstract: The existence of fractures has a considerable influence on the mechanical properties of hydropower high and steep rocky slopes. The method to construct an equivalent rock mass calculation model that reflects the distribution characteristics of three-dimensional (3D) fractures is the key to analyze and evaluate the mechanical properties of rock mass. Based on the theory of damage mechanics and statistical strength, this study proposed a new method to calculate the equivalent rock 3D random fractured network model using the 3D rock failure process analysis (RFPA3D). First, based on the Baecher model and Monte-Carlo method, the reconstruction of the 3D random discrete fracture network (DFN) model was implemented in the RFPA3D. Furthermore, an equivalent rock 3D random fractured network model of engineering scale was constructed using the embedded DFN model and through giving different mechanical parameters to fractures and rocks. All the types of load combinations can be applied to the model to realize the analysis of the mechanical properties, such as failure process, deformation, and the strength of the 3D random fractured rock mass. The rock mass downstream of the dam site area of the left bank slope of the Lianghekou Hydropower Station was then taken as the background, and the geometric parameters of the joints in the region were analyzed and studied using the 3GSM software. Moreover, the characteristic values and the distribution types of joint geometric parameters in the study area were obtained. Finally, the accuracy of the 3D random DFN model was verified by taking the fractured rock mass downstream of the left bank slope dam site of the Lianghekou Hydropower Station as an example, and the size effect of the fractured rock mass in the study area was studied. Results show that the representative elementary volume of the jointed rock mass is evaluated as 8 m × 8 m × 8 m, and the corresponding equivalent uniaxial compressive strength and elastic modulus are 25.159 MPa and 19.443 GPA, respectively. Research results provide a new method for the study of the mechanical behavior of the equivalent rock mass. -
圖 1 節理的透視化模型。（a）一組節理面；（b）兩組節理面；（c）三組節理面
Figure 1. Perspective model of fracture: (a) a set of joint planes; (b) two sets of joint planes; (c) three sets of joint planes
圖 2 等效巖體三維隨機節理網絡模型的構建。（a）巖石模型；（b）DFN模型；（c）等效巖體模型
Figure 2. Construction of three-dimensional random DFN model of equivalent rock mass: (a) rock model; (b) DFN model; (c) equivalent rock mass model
圖 3 基于3GSM軟件節理分布圖。（a）壩址區下游處邊坡巖體；（b）上半球赤平投影圖
Figure 3. Fracture distribution diagrams based on 3GSM: (a) slope rock mass downstream of dam site; (b) stereogram of the upper hemisphere
圖 4 1#節理面幾何參數概率分布直方圖。（a）節理面傾向；（b）節理面傾角；（c）節理面跡長；（d）節理面間距
Figure 4. Probability distribution histogram of geometric parameters of 1# fracture surfaces: (a) joint plane dip; (b) joint plane inclination; (c) trace length of joint surface; (d) joint plane spacing
圖 5 等效巖體三維隨機DFN模型剖面截取。（a）節理面剖面；（b）節理面剖面出露跡線
Figure 5. Profile capture of three-dimensional random DFN model of equivalent rock mass: (a) joint surface profile; (b) exposed trace of joint surface profile
圖 6 三維節理巖體尺寸效應研究。（a）L= 1 m；（b）L= 2 m；······；（f）L= 12 m
Figure 6. Scale effect of three-dimensional fractured rock mass: (a) model side length is 1 m; (b) model side length is 2 m; ······; (f) model side length is 12 m
圖 7 數值模擬結果。（a）巖體力學參數尺寸效應；（b）巖體力學參數變化系數隨模型變化規律
Figure 7. Numerical simulation results: (a) scale effect of rock mass mechanical parameters; (b) variation law of rock mass mechanical parameter variation coefficient with model size
表 1 節理面幾何參數的概率分布及數值
Table 1. Probability distribution and value of geometric parameters of fractures
Joint plane Inclination/(°) Dip angle/(°) Mean value of bulk density/ m?3 Distribution type Mean value Standard deviation Distribution type Mean value Standard deviation 1# Normal 235.15 6.48 Normal 25.98 8.41 0.01734 2# Lognormal 351.34 0.15 Lognormal 28.16 0.83 0.02020 3# Normal 94.73 13.68 Normal 85.80 9.92 0.05838 Joint plane Trace length/m Spacing/m Distribution type Mean value Standard deviation Distribution type Mean value Standard deviation 1# Lognormal 3.42 2.05 Negative exponential 1.35 1.21 2# Normal 3.12 1.48 Lognormal 1.70 1.55 3# Lognormal 2.96 1.39 Negative exponential 0.69 0.7 
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表 2 等效巖體三維節理網絡模擬數據檢驗
Table 2. Verification of three-dimensional DFN model data of equivalent rock mass
Parameter Simulation value Measured value Error /% 1# joint plane 2# joint plane 3# joint plane 1# joint plane 2# joint plane 3# joint plane 1# joint plane 2# joint plane 3# joint plane Dip angle 27.35 31.24 83.36 25.98 28.16 85.80 5.27 10.94 2.84 Trace length 3.61 2.95 3.24 3.42 3.12 2.96 5.56 5.45 9.46 Bulk density 0.015 0.022 0.054 0.017 0.020 0.058 11.74 10.00 7.14
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久色视频表 3 研究區域內巖石和節理的參數
Table 3. Parameters of rocks and fractures in the study area
Material type Heterogeneity Uniaxial compressive strength/MPa Elastic modulus /GPa Friction angle / (°) Poisson’s ratio Rock 5 108.9 37.6 56 0.24 Joint 2 5.45 1.88 30 0.39
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參考文獻
[1] Wang X M, Du Y F, Liang X L. Investigation of the representative elementary volume of fractured rock mass using the homogeneity index. Hydroge Eng Geol, 2021, 48(2): 55 [2] Wang H T, Chen X Y, Liu Y M, et al. Study on structure features of deep rock in Yanqianshan iron mine. Mod Min, 2019, 35(6): 74 doi: 10.3969/j.issn.1674-6082.2019.06.019王恒濤, 陳曉云, 劉育明, 等. 眼前山鐵礦深部礦巖結構特征分析. 現代礦業, 2019, 35(6):74 doi: 10.3969/j.issn.1674-6082.2019.06.019 [3] Lei G W, Yang C H, Wang G B, et al. Geometric features of joints and quality evaluation of rock mass in Xinchang section, Beishan. Chin J Rock Mech Eng, 2016, 35(5): 896雷光偉, 楊春和, 王貴賓, 等. 北山預選區新場地段巖體節理幾何特征及評價. 巖石力學與工程學報, 2016, 35(5):896 [4] Du Y, Xie M W, Jiang Y J, et al. Experimental study on cumulative damage assessment of rock-block using a laser Doppler vibrometer. Chin J Eng, 2017, 39(1): 141杜巖, 謝謨文, 蔣宇靜, 等. 應用激光多普勒測振儀的巖塊體累計損傷評價試驗研究. 工程科學學報, 2017, 39(1):141 [5] Xu D, Feng X T, Li S J, et al. In-situ testing technique for tunnel deformation and structural plane of rock mass based on contactless laser scanning method and its application. Chin J Geotech Eng, 2018, 40(7): 1336許度, 馮夏庭, 李邵軍, 等. 激光掃描隧洞變形與巖體結構面測試技術及應用. 巖土工程學報, 2018, 40(7):1336 [6] Jiang M C, Lin J F, Yuan H L, et al. Application of 3D laser scanning in rock mass integrity analysis of the slope in a super bridge. Geotech Investig Surv, 2020, 48(9): 66江木春, 林劍鋒, 袁海龍, 等. 三維激光掃描在某特大橋斜坡巖體完整性分析中應用探索. 工程勘察, 2020, 48(9):66 [7] Du S G. Method of equal accuracy assessment for the stability analysis of large open-pit mine slopes. Chin J Rock Mech Eng, 2018, 37(6): 1301杜時貴. 大型露天礦山邊坡穩定性等精度評價方法. 巖石力學與工程學報, 2018, 37(6):1301 [8] Wang F Y, Zhao M Y, Wang M C, et al. Application of UAV photogrammetry in mine geological environment survey. J Jilin Univ Earth Sci Ed, 2020, 50(3): 866王鳳艷, 趙明宇, 王明常, 等. 無人機攝影測量在礦山地質環境調查中的應用. 吉林大學學報(地球科學版), 2020, 50(3):866 [9] Cao J, Chen G L, Wan C C, et al. Application of ShapeMetrix3D system in the engineering geology survey of Jiama copper mine. China Min Mag, 2018, 27(Suppl 1): 320曹俊, 陳國良, 萬串串, 等. ShapeMetrix3D系統在甲瑪礦工程地質調查中的應用. 中國礦業, 2018, 27(增刊1): 320 [10] Cai H Y, Zhang Y P, Wang T, et al. Optimal selection and design of residual ore recovery method based on 3GSM stability evaluation of rock mass. Min Res Dev, 2018, 38(12): 17蔡漢玉, 張耀平, 王濤, 等. 基于3GSM巖體穩定性評價的殘礦回收方法優選及設計. 礦業研究與開發, 2018, 38(12):17 [11] Pham H, Parashar R, Sund N, et al. A method to represent a well in a three-dimensional discrete fracture network model. Groundwater, 2021, 59(2): 281 doi: 10.1111/gwat.13030 [12] Zhang Y, Peng L W. Study on the three-dimensional crack network model of rock mass based on Monte-Carlo. J Gansu Sci, 2020, 32(2): 124張亞, 彭樂文. 基于Monte-Carlo的巖體三維裂隙網絡模型研究. 甘肅科學學報, 2020, 32(2):124 [13] Liu B, Jin A B, Gao Y T, et al. Construction method research on DFN model based on fractal geometry theory. Rock Soil Mech, 2016, 37(Suppl 1): 625劉波, 金愛兵, 高永濤, 等. 基于分形幾何理論的DFN模型構建方法研究. 巖土力學, 2016, 37(增刊1): 625 [14] Wu S C, Zhou Y, Gao Y T, et al. Research on construction method of stochastic joints 3d-network model of equivalent rock mass. Chin J Rock Mech Eng, 2012, 31(Suppl 1): 3082吳順川, 周喻, 高永濤, 等. 等效巖體隨機節理三維網絡模型構建方法研究. 巖石力學與工程學報, 2012, 31(增刊1): 3082 [15] Elmo D, Stead D. An integrated numerical modelling-discrete fracture network approach applied to the characterisation of rock mass strength of naturally fractured Pillars. Rock Mech Rock Eng, 2010, 43(1): 3 doi: 10.1007/s00603-009-0027-3 [16] Jin A B, Wang B X, Zhao Y Q, et al. Analysis of the deformation and fracture of underground mine roadway by joint rock mass numerical model. Arab J Geosci, 2019, 12(18): 1 [17] Vazaios I, Farahmand K, Vlachopoulos N, et al. Effects of confinement on rock mass modulus: A synthetic rock mass modelling (SRM) study. J Rock Mech Geotech Eng, 2018, 10(3): 436 doi: 10.1016/j.jrmge.2018.01.002 [18] Wang X Q, Kang H P, Gao F Q, et al. DEM simulation of mechanical behavior of jointed coal in large scale under uniaxial compression. J China Coal Soc, 2018, 43(11): 3088王曉卿, 康紅普, 高富強, 等. 大尺寸節理煤體單軸壓縮力學行為的離散元模擬研究. 煤炭學報, 2018, 43(11):3088 [19] Wu Q, Tang H M, Wang L Q, et al. Three-dimensional distinct element simulation of size effect and spatial anisotropy of mechanical parameters of jointed rock mass. Chin J Rock Mech Eng, 2014, 33(12): 2419吳瓊, 唐輝明, 王亮清, 等. 基于三維離散元仿真試驗的復雜節理巖體力學參數尺寸效應及空間各向異性研究. 巖石力學與工程學報, 2014, 33(12):2419 [20] Cui Z, Sheng Q. Numerical modelling of structural effect of equivalent mechanical parameters of fractured rock mass. Rock Soil Mech, 2018, 39(10): 3830崔臻, 盛謙. 裂隙巖體等效力學參數結構效應的計算機模擬試驗研究. 巖土力學, 2018, 39(10):3830 [21] Yang Z M, Gao Y T, Wu S C, et al. Study of the influence of joint parameters on rock mass strength based on equivalent rock mass technology. J China Univ Min Technol, 2018, 47(5): 979楊忠民, 高永濤, 吳順川, 等. 基于等效巖體技術的節理參數對巖體強度影響性研究. 中國礦業大學學報, 2018, 47(5):979 [22] Mei T. Study on Optimization of 3D Joint Network Simulation in Rock Mass and Its Application in Jijicao Block, Beishan, Gansu Province [Dissertation]. Wuhan: Chinese Academy of Sciences (Wuhan Institute of Geotechnical Mechanics), 2008梅濤. 巖體節理三維網絡模擬優化及在甘肅北山芨芨槽巖塊的應用研究[學位論文]. 武漢: 中國科學院研究生院(武漢巖土力學研究所), 2008 [23] Wu S C, Gao Y H, Gao Y T, et al. Research on representative elemental volume of equivalent joint rock mass. J China Univ Min Technol, 2014, 43(6): 1120吳順川, 高艷華, 高永濤, 等. 等效節理巖體表征單元體研究. 中國礦業大學學報, 2014, 43(6):1120 [24] Liang Z Z. Three-Dimensional Failure Process Analysis of Rock and Associated Numerical Tests [Dissertation]. Shenyang: Northeastern University, 2005梁正召. 三維條件下的巖石破裂過程分析及其數值試驗方法研究[學位論文]. 沈陽: 東北大學, 2005 [25] Lang Y X, Liang Z Z, Dong Z. Three-dimensional microscopic model reconstruction of basalt and numerical direct tension tests. Chin J Eng, 2019, 41(8): 997郎穎嫻, 梁正召, 董卓. 玄武巖三維細觀孔隙模型重構與直接拉伸數值試驗. 工程科學學報, 2019, 41(8):997 [26] Priest S D, Hudson J A. Discontinuity spacings in rock. Int J Rock Mech Min Sci Geomech Abstr, 1976, 13(5): 135 doi: 10.1016/0148-9062(76)90818-4 [27] Yang J P, Chen W Z, Dai Y H, et al. Numerical determination of elastic compliance tensor of fractured rock masses by finite element modeling. Int J Rock Mech Min Sci, 2014, 70: 474 doi: 10.1016/j.ijrmms.2014.06.007 [28] Liang Z Z, Wu N, Li Y C, et al. Numerical study on anisotropy of the representative elementary volume of strength and deformability of jointed rock masses. Rock Mech Rock Eng, 2019, 52(11): 4387 doi: 10.1007/s00603-019-01859-9 -
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