Abstract：The difference between the samples affects the discreteness of the direct shear test results and more importantly the rationality of the analysis results of the shear strength parameters of the multiple test sample method of jointed rock mass. For this reason, the single-joint sandstone samples are prepared by using the splitting method, and the joint surface morphology scanning analysis and direct shear tests are carried out. The results indicate that: (1) Due to the limitation of the sample preparation conditions, the difference between the samples is unavoidable. The non-uniformity of the samples leads to the discreteness of the test results, so that the order of use of the samples directly affects the distribution of the test results. (2) Based on the empirical formula for the shear strength of joint surfaces established by Barton, a single test sample method is proposed to determine the JRC and shear strength parameters of the joint surface of the samples through the scanning analysis of topography of single sample joint surface or single direct shear test, so as to provide a better idea for quantitative analysis of the difference in shear strength parameters between the same sample. (3) A comprehensive analysis method for the shear strength of jointed rock mass based on the single sample method is proposed. The shear strength test values and calculated values of the same set of samples under different normal stresses are fitted together, so that the shear mechanical properties of the samples under different normal stresses are reflected. It can more accurately reflect the distribution of shear mechanical properties of the joint surface of the samples, and can eliminate the influences of the order of use of the samples on the test results.
邓华锋, 熊雨, 肖瑶, 齐豫, 李涛, 许晓亮. 基于单试件法的节理岩体抗剪强度参数分析[J]. 岩土工程学报, 2020, 42(8): 1509-1515.
DENG Hua-feng, XIONG Yu, XIAO Yao, QI Yu, LI Tao, XU Xiao-liang. Shear strength parameters of jointed rock mass based on single test sample method. Chinese J. Geot. Eng., 2020, 42(8): 1509-1515.
[1] 刘健, 陈亮, 刘建锋, 等. 深部花岗岩中天然开启节理剪切性能试验研究[J]. 地下空间与工程学报, 2017, 13(1): 63-70. (LIU Jian, CHEN Liang, LIU Jian-feng, et al.Experimental study on shear behavior of naturally opened joint in deep granit[J]. Chinese Journal of Underground Space and Engineering, 2017, 13(1): 63-70. (in Chinese)) [2] 赵坚. 岩石节理剪切强度的JRC-JMC新模型[J]. 岩石力学与工程学报, 1998, 17(4): 349-357. (ZHAO Jian.A new model of JRC-JMC for rock joint shear strength[J]. Chinese Journal of Rock Mechanics and Engineering, 1998, 17(4): 349-357. (in Chinese)) [3] 周扬一, 冯夏庭, 徐鼎平, 等. 含不同胶结充填物的碳酸盐岩层面剪切力学特性试验研究[J]. 岩石力学与工程学报, 2016, 35(6): 1161-1172. (ZHOU Yang-yi, FENG Xia-ting, XU Ding-ping, et al.Experimental study on shear mechanical properties of carbonate rock layers with different cementation fillings[J]. Chinese Journal of Rock Mechanics and Engineering, 2016, 35(6): 1161-1172. (in Chinese)) [4] 杨洁, 荣冠, 程龙, 等. 节理峰值抗剪强度试验研究[J]. 岩石力学与工程学报, 2015, 34(5): 884-894. (YANG Jie, RONG Guan, CHENG Long, et al.Experimental study on peak shear strength of joints[J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(5): 884-894. (in Chinese)) [5] 孙辅庭, 佘成学, 万利台, 等. 基于三维形貌特征的岩石节理峰值剪切强度准则研究[J]. 岩土工程学报, 2014, 36(3): 529-536. (SUN Fu-ting, YAN Cheng-xue, WAN Li-tai, et al.Study on peak shear strength criterion of rock joints based on three-dimensional topography[J]. Journal of Geotechnical Engineering, 2014, 36(3): 529-536. (in Chinese)) [6] 夏才初, 唐志成, 宋英龙. 基于三维形貌参数的偶合节理峰值抗剪强度公式[J]. 岩石力学与工程学报, 2013, 32(增刊1): 2833-2839. (XIA Cai-chu, TANG Zhi-cheng, SONG Ying-long.The formula of peak joint shear strength of coupled joints based on three-dimensional shape parameters[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32(S1): 2833-2839. (in Chinese)) [7] 唐志成, 刘泉声, 夏才初. 节理三维形貌参数的采样效应与峰值抗剪强度准则[J]. 中南大学学报(自然科学版), 2015, 46(7): 2524-2531. (TANG Zhi-cheng, LIU Quan-sheng, XIA Cai-chu.Investigation of three-dimensional roughness scale-dependency and peak shear strength criterion[J]. Journal of Central South University (Natural Science Edition), 2015, 46(7): 2524-2531. (in Chinese)) [8] 尤明庆, 华安增. 岩石试样的强度准则及内摩擦系数[J]. 地质力学学报, 2001, 7(1): 53-60. (YOU Ming-qing, HUA An-zeng.Strength criterion and internal friction coefficient of rock specimens[J]. Journal of Geomechanics, 2001, 7(1): 53-60. (in Chinese)) [9] 徐颖, 李振平, 葛新. 软岩单试件直剪实验方法[J]. 辽宁工程技术大学学报, 2006, 25(3): 367-368. (XU Ying, LI Zhen-ping, GE Xin.Soft rock single test sample shear experiment methord[J]. Journal of Liaoning Technical University, 2006, 25(3): 367-368. (in Chinese)) [10] HOU Y P, SUN T Q.An improved method to make the microdroplet single fiber composite specimen for determining the interfacial shear strength[J]. Journal of Materials Science, 2012, 47(11): 4775-4778. [11] YAN K F, ZHANG C Y, QIAO S R, et al.Measurement of in-plane shear strength of carbon/carbon composites by compression of double-notched specimens[J]. Journal of Materials Engineering & Performance, 2012, 21(1): 62-68. [12] 孙辅庭, 佘成学, 蒋庆仁. 一种新的岩石节理面三维粗糙度分形描述方法[J]. 岩土力学, 2013, 34(8): 2238-2242. (SUN Fu-ting, SHE Cheng-xue, JIANG Qing-ren.A new fractal description method for three-dimensional roughness surface of rock joint[J]. Rock and Soil Mechanics, 2013, 34(8): 2238-2242. (in Chinese)) [13] 陈世江, 朱万成, 刘树新, 等. 岩体结构面粗糙度各向异性特征及尺寸效应分析[J]. 岩石力学与工程学报, 2015, 34(1): 57-66. (CHEN Shi-jiang, ZHU Wan-cheng, LIU Shu-xin, et al.Anisotropy and size effects of surface roughness of rock joints[J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(1): 57-66. (in Chinese)) [14] 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(增刊1): 2747-2753. (DU Shi-gui, HU Xiao-fei, GUO Wei, et al.Comparative study of JRC-JCS model and direct shear test[J]. Chinese Journal of Rock Mechanics and Engineering, 2008, 27(S1): 2747-2753. (in Chinese)) [15] 曹平, 贾洪强, 刘涛影, 等. 岩石节理表面三维形貌特征的分形分析[J]. 岩石力学与工程学报, 2011, 30(增刊2): 3839-3843. (CAO Ping, JIA Hong-qiang, LIU Tao-ying, et al.Fractal analysis of three dimensional topography characteristics of rock joint surface[J]. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(S2): 3839-3843. (in Chinese)) [16] 陈世江, 朱万成, 王创业, 等. 岩体结构面粗糙度系数定量表征研究进展[J]. 力学学报, 2017, 49(2): 239-256. (CHEN Shi-jiang, ZHU Wan-cheng, WANG Chuang-ye, et al.Review of research progresses of the quantifying joint roughness coefficient[J]. Chinese Journal of Theoretical and Applied Mechanics, 2017, 49(2): 239-256. (in Chinese)) [17] PATTON F D. Multiple modes of shear failure in rock[C]// Proceedings of the 1st ISRM Congress, 1966, Lisbon, Portugal: 509-513. [18] BARTON N, CHOUBEY V.The shear strength of rock joints in theory and practice[J]. Rock Mechanics and Rock Engineering, 1977, 10(1): 1-54. [19] GEERTSEMA A J.The shear strength of planar joints in mudstone[J]. International Journal of Rock Mechanics and Mining Sciences, 2002, 39(8): 1045-1049. [20] DU S G, HU Y J, HU X F Comparison between empirical estimation by JRC-JCS mode and direct shear test for joint shear strength[J]. Journal of Earth Science, 2011, 22: 411-420. [21] SOW D, RIVARD P, PEYRAS L Comparison of joint shearing resistance obtained with the Burton and Choubey criterion and with direct shear tests[J]. Rock Mechanics and Rock Engineering, 2016, 49: 3357-3361. [22] HE J M, XU M H, MA D X.The application of Barton structural plane shear strength formula in Murum hydropower station, Malaysia[J]. Resources Environment & Engineering, 26(5): 542-544. (in Chinese)
