以直剪試驗及數值模型探討節理岩體之剪力強度與微觀力學機制

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姓名

黎慶(Le Hoang Khanh) 查詢紙本館藏

畢業系所

土木工程學系

論文名稱

以直剪試驗及數值模型探討節理岩體之剪力強度與微觀力學機制
(The relationship of shear strengths and micromechanical behaviors of jointed specimens by direct shear tests and discrete element models)

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至系統瀏覽論文 (2024-9-1以後開放)

摘要(中)

節理與層面等不連續面之岩體抗剪強度為岩土工程評估岩質邊坡和隧道穩定性之關鍵因素。Barton公式是評估岩石節理剪切強度的最廣泛使用的方法之一。在方程式中，節理粗糙度係數 (JRC)為影響剪切強度之關鍵因子，係因其為控制不連續面粗糙度之重要參數。
在先前的研究中顯示，藉由Excel以常態分佈可創造特定JRC之剖面，並據以製作研究所需之人造節理試體進行直剪試驗。
本研究透過物理試驗和數值模擬（Discrete Element Method,簡稱DEM），對軟和中等強度岩石節理進行了一系列直剪試驗與數值模擬分析，並探討隨機生成 JRC 剖面之力學特性。其中，控制 JRC 值（20、19.6 和 10）的節理粗糙度是藉由 Le (2018)等人提出的 PHV 方法生成。
首先，物理試驗是以3D列印製作模型，並澆置JRC為19.6之石膏樣本，其無圍壓縮強度為4.42 MPa 比照軟岩。其次，將石膏樣本以光掃描後計算實際 JRC為 16.8。接著，運用2D-DEM採實際JRC建置數值模型，並進行石膏節理不連續面數值模擬。此外，本研究亦使用不同JRC之水泥試體進行直剪試驗與數值模擬，並與石膏試體的測試結果進行比較。其中，水泥試體之控制JRC分別為20、19.6 及 10，其掃描得到實際JRC分別為 10、11 及 2.4，其無圍壓縮強度為37.1 MPa比照中等岩石。

摘要(英)

The shear strength of rock mass containing discontinuities, such as joints and bedding planes, plays an essential role in estimating the stability of a rock slope and tunnels in rock engineering. Barton′s formula is one of the most widely used equations for estimating the shear strength of rock joints. The Joint Roughness Coefficient (JRC) in the equation is a crucial parameter of the shear strength because it controls the profile′s roughness. In this study, a series of direct shear tests in both laboratory and numerical modeling (through Discrete Element Method, DEM) was conducted for soft and medium strength rock joints to elucidate the mechanical properties of a randomly-generated JRC profile. The joint profile with a given JRC value (20, 19.6, and 10) was generated using the PHV approach proposed by Le et al. (2018). The artificial gypsum specimen (soft rock with UCS=4.42 MPa) with JRC=19.6 was replicated from the 3D-printed joint block in the laboratory. The actual JRC of the joint gypsum specimen was then light-scanned and re-estimated as 16.8. Afterward, 2D-DEM was employed to simulate the joint gypsum model with the same actual JRC as in the laboratory. Besides, a series of artificial cement specimens with different JRC were also cast using a cement mixture (medium rock with UCS=37.1 MPa) for comparison with the test results of gypsum specimens. The actual JRC values of joint profiles of artificial cement specimens (with given JRCs of 20, 19.6, and 10) are recalculated as 10, 11, and 2.4, respectively. The DS simulation on cement specimens was also performed.

關鍵字(中)

★ 直剪試驗
★ 2D-DEM數值模型
★ 人造節理
★ 微觀力學行為
★ 殘餘剪切強度

關鍵字(英)

★ direct shear test
★ 2D-DEM model
★ artificial joint
★ micromechanical behavior
★ residual shear strength

論文目次

摘要 i
Abstract ii
DECLARATION iii
List of Tables vii
List of Figures ix
Explaination of symbols xix
Chapter I Introduction 1
1.1 Overview 1
1.2 Content of the dissertation 5
Chapter II Literature review 6
2.1 Research background 6
2.2 Importance of peak and residual shear strength 23
2.3 Review of current methods for JRC estimation 30
2.3.1 JRC estimation based on Barton’s standard profiles 30
2.3.2 JRC estimation based on the root mean square value Z2 32
2.3.3 JRC estimation based on the fitting parameter C 33
2.3.4 JRC estimation based on the fractal dimension parameter D 36
2.3.5 JRC estimation based on the PHV method 38
2.4 Review of 3D-printing technology 47
Chapter III Methodology 49
3.1 Material and test apparatus 49
3.1.1 Material 49
3.1.2 UCS equipment 52
3.1.3 Application of 3D-printing technology and PHV method 56
3.1.4 3D scanner 62
3.1.5 DS equipment 71
3.2 Performance of Particle Flow Code (PFC2D version 5.0) 78
3.2.1 Introduction 78
3.2.2 Constitutive models used in PFC2D in this study 79
3.2.3 Formation of UCS, DS models, and required model parameters 82
3.2.4 Model calibration 90
3.3 Plans for performing lab tests and numerical simulations 94
Chapter IV Direct shear test results and discussion 98
4.1 Direct shear results of artificial gypsum specimens 98
4.2 Direct shear result of artificial cement specimens 102
4.3 Comparison in profile change of the joint surface of artificial specimens after the test 110
4.3.1 Profile change of the joint surface of artificial gypsum specimens 110
4.3.2 Profile change of the joint surface of artificial cement specimens 115
4.4 Influence of the JRC on the shear strength of jointed cement specimens 124
4.5 Influence of the UCS on the behavior of the stress-displacement curve and failure mechanism of the jointed specimens 127
Chapter V Numerical simulation results 129
5.1 Results of numerical simulation on gypsum specimens and comparison with the lab test result 129
5.2 Results of numerical simulation on cement specimens and comparison with the lab test result 137
5.3 Exploring the micromechanical behavior of the joint model 154
5.3.1 Distribution of contact forces of DS models during shearing 154
5.3.2 Development of fractures of DS models during shearing 168
Chapter VI Residual shear strength of artificial joint specimens 181
6.1 Calculation of the mobilized JRC after the test 181
6.2 Estimation of the mobilized friction angle 184
6.3 Estimation of the residual shear strength 187
6.4 Estimation of residual shear strength for gypsum specimens using the empirical formula in this study 188
6.5 Estimation of residual shear strength for Liu et al.’s test data (2020) using the empirical formula in this study 190
Chapter VII Conclusions and Suggestions 193
7.1 Conclusions 193
7.2 Suggestions 199
References 200

參考文獻

Asadollahi, P. and F. Tonon, Constitutive model for rock fractures: Revisiting Barton′s empirical model. Engineering Geology, 2010. 113(1): p. 11-32.
Asadollahi, P., 2009. Stability analysis of a single three dimensional rock block: effect of dilatancy and high-velocity water jet impact, PhD Dissertation, University of Texas at Austin.
Bandis, S., A.C. Lumsden, and N.R. Barton, Experimental studies of scale effects on the shear behaviour of rock joints. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1981. 18(1): p. 1-21.
Bandis, S.C., A.C. Lumsden, and N.R. Barton, Fundamentals of rock joint deformation. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1983. 20(6): p. 249-268.
Barton, N. and V. Choubey, The shear strength of rock joints in theory and practice. Rock mechanics, 1977. 10(1): p. 1-54.
Barton, N., Modelling rock joint behavior from in situ block tests: Implications for nuclear waste repository design. 1982.
Barton, N., Review of a new shear-strength criterion for rock joints. Engineering Geology, 1973. 7(4): p. 287-332.
Belem, T., F. Homand-Etienne, and M. Souley, Quantitative parameters for rock joint surface roughness. Rock Mechanics and Rock Engineering, 2000. 33(4): p. 217-242.
Cheng, C., X. Chen, and S. Zhang, Multi-peak deformation behavior of jointed rock mass under uniaxial compression: Insight from particle flow modeling. Engineering Geology, 2016. 213: p. 25-45.
Cundall, P.A. A computer model for simulating progressive, large-scale movements in blocky rock systems. 1971.
Cundall, P.A. and O.D.L. Strack, A discrete numerical model for granular assemblies. Géotechnique, 1979. 29(1): p. 47-65.
Dang, W., H. Konietzky, and T. Frühwirt, Direct shear behavior of a plane joint under dynamic normal load (DNL) conditions. Engineering Geology, 2016. 213: p. 133-141.
Fan, X., P.H.S.W. Kulatilake, and X. Chen, Mechanical behavior of rock-like jointed blocks with multi-non-persistent joints under uniaxial loading: A particle mechanics approach. Engineering Geology, 2015. 190: p. 17-32.
Feng, P., et al., Mechanical properties of structures 3D printed with cementitious powders. Construction and Building Materials, 2015. 93: p. 486-497.
Fereshtenejad, S. and J.-J. Song, Fundamental Study on Applicability of Powder-Based 3D Printer for Physical Modeling in Rock Mechanics. Rock Mechanics and Rock Engineering, 2016. 49(6): p. 2065-2074.
Grasselli, G. and P. Egger, Constitutive law for the shear strength of rock joints based on three-dimensional surface parameters. International Journal of Rock Mechanics and Mining Sciences, 2003. 40(1): p. 25-40.
Guo, S. and S. Qi, Numerical study on progressive failure of hard rock samples with an unfilled undulate joint. Engineering Geology, 2015. 193: p. 173-182.
He, L., et al., Empirical Shear Strength Criterion for Rock Joints Based on Joint Surface Degradation Characteristics During Shearing. Rock Mechanics and Rock Engineering, 2020. 53(8): p. 3609-3624.
Huang, W.-C., et al., Micromechanical behavior of granular materials in direct shear modeling. Journal of the Chinese Institute of Engineers, 2015. 38.
Invernizzi, M., 2009, Application of a modified Barton′s model for the stability analysis of keyblocks in rock tunnels. MSc Thesis, Politecnico di Torino.
Itasca Consulting Group Inc. 2017. Particle Flow Code in 2 Dimensions (PFC2D version 5.0) – Theory and Background. Minneapolis, MN: Itasca Consulting Group.
Jiang, M., et al., Modeling failure of jointed rock slope with two main joint sets using a novel DEM bond contact model. Engineering Geology, 2015. 193: p. 79-96.
Jing, L., E. Nordlund, and O. Stephansson, An experimental study on the anisotropy and stress-dependency of the strength and deformability of rock joints. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1992. 29(6): p. 535-542.
Ju, Y., et al., Visualization and Transparentization of the Structure and Stress Field of Aggregated Geomaterials Through 3D Printing and Photoelastic Techniques. 2017.
Kana, D.D., D.J. Fox, and S.M. Hsiung, Interlock/friction model for dynamic shear response in natural jointed rock. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1996. 33(4): p. 371-386.
Klinkenberg, B., A review of methods used to determine the fractal dimension of linear features. Mathematical Geology, 1994. 26(1): p. 23-46.
Lê, H.K., et al., Spatial characteristics of rock joint profile roughness and mechanical behavior of a randomly generated rock joint. Engineering Geology, 2018. 245: p. 97-105.
Le, H.-K., W.-C. Huang, and C.-C. Chien, Exploring micromechanical behaviors of soft rock joints through physical and DEM modeling. Bulletin of Engineering Geology and the Environment, 2021. 80(3): p. 2433-2446.
Lee, Y.H., et al., The fractal dimension as a measure of the roughness of rock discontinuity profiles. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1990. 27(6): p. 453-464.
Liu, Q., et al., Updates to JRC-JCS model for estimating the peak shear strength of rock joints based on quantified surface description. Engineering Geology, 2017. 228: p. 282-300.
Liu, X.G., et al., Estimation of the joint roughness coefficient of rock joints by consideration of two-order asperity and its application in double-joint shear tests. Engineering Geology, 2017. 220: p. 243-255.
Meng, F., et al., Comparative study on dynamic shear behavior and failure mechanism of two types of granite joint. Engineering Geology, 2018. 245: p. 356-369.
Myers, N.O., Characterization of surface roughness. Wear, 1962. 5(3): p. 182-189.
Pickering, C. and A. Aydin, Modeling Roughness of Rock Discontinuity Surfaces: A Signal Analysis Approach. Rock Mechanics and Rock Engineering, 2016. 49(7): p. 2959-2965.
Potyondy, D.O. and P.A. Cundall, A bonded-particle model for rock. International Journal of Rock Mechanics and Mining Sciences, 2004. 41(8): p. 1329-1364.
Potyondy, D.O., The bonded-particle model as a tool for rock mechanics research and application: current trends and future directions. Geosystem Engineering, 2015. 18(1): p. 1-28.
Qunyi Liu, W.X., Ying Li, Numerical Built-In Method for the Nonlinear JRC/JCS Model in Rock Joint. The Scientific World Journal, 2014. 2014: p. 7.
Singh, H.K. and A. Basu, Evaluation of existing criteria in estimating shear strength of natural rock discontinuities. Engineering Geology, 2018. 232: p. 171-181.
Singh, H.K. and A. Basu, Shear behaviors of ‘real’ natural un-matching joints of granite with equivalent joint roughness coefficients. Engineering Geology, 2016. 211: p. 120-134.
Tatone, B.S.A. and G. Grasselli, A new 2D discontinuity roughness parameter and its correlation with JrC. International Journal of Rock Mechanics and Mining Sciences, 2010. 47(8): p. 1391-1400.
Tse, R. and D.M. Cruden, Estimating joint roughness coefficients. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 1979. 16(5): p. 303-307.
Usefzadeh, A., et al., Empirical and mathematical formulation of the shear behavior of rock joints. Engineering Geology, 2013. 164: p. 243-252.
Wang, J. and M. Gutierrez, Discrete element simulations of direct shear specimen scale effects. Geotechnique, 2010. 60(5): p. 395-409.
Wang, L., et al., Determination of two-dimensional joint roughness coefficient using support vector regression and factor analysis. Engineering Geology, 2017. 231: p. 238-251.
Wang, P., et al., Evaluation of the anisotropy and directionality of a jointed rock mass under numerical direct shear tests. Engineering Geology, 2017. 225: p. 29-41.
Zhou, T. and J. Zhu, Identification of a suitable 3D printing material for mimicking brittle and hard rocks and Its brittleness enhancements. 2017.

指導教授

黃文昭

審核日期

2021-9-1

推文