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| EXPERIMENTAL STUDY OF SHEAR STRENGTH OF JOINTS WITH FIRST-ORDER AND SECOND-ORDER ASPERITIES |
| ZHU Xiaoming1，2，LI Haibo1，LIU Bo1，ZOU Fei1，MO Zhenze1，YANG Fengwei1，HAO Yafei1 |
(1. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy
of Sciences，Wuhan，Hubei 430071，China；2. Gansu Provincial Transportation Planning，Survey and Design Institute Co.，Ltd.，Lanzhou，Gansu 730000，China) |
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Abstract Simulated rock joint samples with different first-order and second-order asperity heights are casted by high strength gypsum material. A series of CNL(constant normal load) shear tests are carried out to study the shear strength characteristics of joints with different first-order and second-order asperity heights under different normal stresses. The influences of first-order and second-order asperity heights and normal stress on shear strength are analyzed. Based on the experimental results，it can be found that the joint samples with second-order asperity have multi-peak shear stresses，while the joint samples only with first-order asperity have not apparent peak shear stress. The shear strength increases with the increasing first-order and second-order asperity heights and normal stress. With the increasing ratio of second-order asperity height to first-order asperity height，shear strength first increases and then decreases. Finally，an empirical formula is proposed by regression analysis of experimental data to predict the shear strength. The formula can reflect the influences of first-order and second-order asperity heights and normal stress on shear strength.
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Received: 05 January 2011
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| [1] 李海波，冯海鹏，刘 博. 不同剪切速率下岩石节理的强度特性研究[J]. 岩石力学与工程学报，2006，25(12)：2 435–2 440.(LI Haibo，FENG Haipeng，LIU Bo. Study on strength behaviors of rock joints under different shearing deformation velocities[J]. Chinese Journal of Rock Mechanics and Engineering，2006，25(12)：2 435–2 440.(in Chinese))
[2] 李海波，刘 博，冯海鹏，等. 模拟岩石节理试样剪切变形特征和破坏机制研究[J]. 岩土力学，2008，29(7)：1 741–1 746.(LI Haibo，LIU Bo，FENG Haipeng，et al. Study of deformability behaviour and failure mechanism by simulating rock joints sample under different loading conditions[J]. Rock and Soil Mechanics，2008，29(7)：1 741– 1 746.(in Chinese))
[3] 刘 博. 节理面循环剪切特性研究[博士学位论文][D]. 北京：中国科学院研究生院，2009.(LIU Bo. Study on mechanical properties of rock joint planes under cyclic shear loading[Ph. D. Thesis][D]. Beijing：Graduate University，Chinese Academy of Sciences，2009.(in Chinese))
[4] 沈明荣，张清照. 规则齿型结构面剪切特性的模型试验研究[J]. 岩石力学与工程学报，2010，29(4)：713–719.(SHEN Mingrong，ZHANG Qingzhao. Experimental study of shear deformation characteristics of rock mass discontinuities with regular surface roughness[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(4)：713–719.(in Chinese))
[5] 杜时贵，胡晓飞，郭 霄，等. JRC-JCS模型与直剪试验对比研究[J]. 岩石力学与工程学报，2008，27(增1)：2 747–2 753.(DU Shigui，HU Xiaofei，GUO Xiao，et al. Comparison study of JRC-JCS model and direct shear test[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(Supp.1)：2 747–2 753.(in Chinese))
[6] 杜时贵，黄 曼，罗战友，等. 岩石结构面力学原型试验相似材料研究[J]. 岩石力学与工程学报，2010，29(11)：2 263–2 270.(DU Shigui，HUANG Man，LUO Zhanyou，et al. Similar material study of mechanical prototype test of rock structural plane[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(11)：2 263–2 270.(in Chinese))
[7] WOO I， FLEURISSON J A，PARK H J. Influence of weathering on shear strength of joints in a porphyritic granite rock mass in Jechon area，South Korea[J]. Geosciences Journal，2010，14(3)：235–328.
[8] BARLA G，BARLA M，MARTINOTTI M E. Development of a new direct shear testing apparatus[J]. Rock Mechanics and Rock Engineering，2010，43(1)：117–122.
[9] JIANG Y J，LI B，TANABASHI Y. Estimating the relation between surface roughness and mechanical properties of rock joints[J]. International Journal of Rock Mechanics and Mining Sciences，2006，43(6)：837–846.
[10] JAFARI M K，AMINI H K，PELLET F，et al. Evaluation of shear strength of rock joints subjected to cyclic loading[J]. Soil Dynamics and Earthquake Engineering，2003，23(7)：619–630.
[11] 夏才初. 工程岩体节理力学[M]. 上海：同济大学出版社，2002：108–109.(XIA Caichu. Joint mechanics of engineering rock mass[M]. Shanghai：Tongji University Press，2002：108–109.(in Chinese))
[12] HUANG X，HAIMSON B C，PLESHA M E，et al. An investigation of the mechanics of rock joints—part I：laboratory investigation[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1993，30(3)：257–269.
[13] PLESHA M E. Constitutive models for rock discontinuities with dilatancy and surface degradation[J]. International Journal for Numerical and Analytical Methods in Geomechanics，1987，11(4)：345–362.
[14] LEE H S，PARK Y J，CHO T F，et al. Influence of asperity degradation on the mechanical behavior of rough rock joints under cyclic shear loading[J]. International Journal of Rock Mechanics and Mining Sciences，2001，38(7)：967–980.
[15] KANA D D，FOX D J，HSIUNG S M. Interlock/friction model for dynamic shear response in natural jointed rock[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts，1996，33(4)：371–386.
[16] HOMAND F，BELEM T，SOULEY M. Friction and degradation of rock joint surfaces under shear loads[J]. International Journal for Numerical and Analytical Methods in Geomechanics，2001，25(10)：973–999.
[17] YANG Z Y，DI C C，YEN K C. The effect of asperity order on the roughness of rock joints[J]. International Journal of Rock Mechanics and Mining Sciences，2001，38(5)：745–752. |
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2011, Vol. 30 
