Research on shear mechanics model of anchored-jointed rock mass#br#
considering normal stress and rock strength
SONG Yang1，FAN Bo2，WANG Heping2
(1. School of Architecture and Transportation，Liaoning Technical University，Fuxin，Liaoning 123000，China；2. School of Civil Engineering，Liaoning Technical University，Fuxin，Liaoning 123000，China)
Abstract：In order to analyze the influence of normal stress and rock strength on anchor bolt anchoring mechanism，three representative rocks，namely red sandstone，limestone and basalt，were selected to carry out direct shear tests of jointed rock mass under different normal stress levels. Based on the test results，according to the statically determinate beam theory and the principle of minimum complementary energy，this paper establishes a shear strength model of joint surface which considers the effect of rock structure and equivalent shear area. And combined with the theoretical calculation formula，this paper analyzes the influence law of rock strength on the axial force and shear force under different anchorage angles. The research shows the anchoring effect of anchor bolts is shown as increasing the equivalent internal friction angle and cohesion of joint surface，and that the greater the rock strength，the greater the contribution of the bolt to the shear strength of the joint plane. Compared with the experimental data and the existing analytical model，the calculated values of the theoretical model are more consistent with the experimental results. Through calculation and analysis，it can be seen that with the increase of the anchorage angle，the contribution of the axial force of the bolt to the shear strength of the joint surface gradually decreases，while the contribution of the shear force to the shear strength of the joint surface gradually increases，and the optimal anchorage angle of the bolt is within the range of 50°to 70°.
宋 洋1，范 波2，王贺平2. 考虑法向应力与岩石强度的加锚节理岩体剪切力学模型研究[J]. 岩石力学与工程学报, 2023, 42(6): 1325-1335.
SONG Yang1，FAN Bo2，WANG Heping2. Research on shear mechanics model of anchored-jointed rock mass#br#
considering normal stress and rock strength. , 2023, 42(6): 1325-1335.
[1] CHEN Y，LI C. Influences of loading condition and rock strength to the performance of rock bolts[J]. Geotechnical Testing Journal，2015，38(2)：207–218.
[2] 刘泉声，雷广峰，彭星新，等. 白砂岩、大理岩及花岗岩加锚剪切力学特性研究[J]. 岩石力学与工程学报，2018，37(增2)：4 007–4 015.(LIU Quansheng，LEI Guangfeng，PENG Xingxin，et al. Research on shear mechanical properties of white sandstone，marble and granite with anchors[J]. Chinese Journal of Rock Mechanics and Engineering，2018，37(Supp.2)：4 007–4 015.(in Chinese))
[3] WU X Z，JIANG Y J，LI B. Influence of joint roughness on the shear behaviour of fully encapsulated rock bolt[J]. Rock Mechanics and Rock Engineering，2018，51(3)：953–959.
[4] LI X，AZIZ N，MIRZAGHORBANALI A，et al. Behavior of fiber glass bolts，rock bolts and cable bolts in shear[J]. Rock Mechanics and Rock Engineering，2016，49(7)：2 723–2 735.
[5] 刘曙光，黄泽信，张 洪. 不同锚固角加锚无摩擦节理面剪切试验研究[J]. 地下空间与工程学报，2022，18(3)：824–831.(LIU Shuguang，HUANG Zexin，ZHANG Hong. Shear test study on frictionless joints with different anchoring angles[J]. Chinese Journal of Underground Space and Engineering，2022，18(3)：824–831.(in Chinese))
[6] 郭浩希. 锚固角度对加锚节理面的剪切特性影响分析[硕士学位论文][D]. 广州：华南理工大学，2019.(GUO Haoxi. Analysis of the influence of anchoring angle on shear characteristics of anchored joint surfaces[M. S. Thesis][D]. Guangzhou：South China University of Technology，2019.(in Chinese))
[7] 何栋梁，杨伟军，林 杭，等. 拉–剪状态下锚固节理剪切强度与破坏模式分析[J]. 公路交通科技，2019，36(4)：95–101.(HE Dongliang，YANG Weijun，LIN Hang，et al. Analysis of shear strength and failure mode of anchoring joints in tension-shear state[J]. Highway Traffic Technology，2019，36(4)：95–101.(in Chinese))
[8] 腾俊洋，张宇宁，唐建新，等. 锚固方式对节理岩体剪切性能影响试验研究[J]. 岩土力学，2017，38(8)：2 279–2 285.(TENG Junyang，ZHANG Yuning，TANG Jianxin，et al. Experimental study on the effect of anchoring methods on the shear performance of jointed rock mass[J]. Rock and Soil Mechanics，2017，38(8)：2 279–2 285.(in Chinese))
[9] 汪小刚，周纪军，贾志欣，等. 加锚节理面的抗剪试验研究 [J]. 岩土力学，2016，37(增2)：250–256.(WANG Xiaogang，ZHOU Jijun，JIA Zhixin，et al. Shear test study of anchored joint surfaces[J]. Rock and Soil Mechanics，2016，37(Supp.2)：250–256.(in Chinese))
[10] PELLET F，EGGER P. Analytical model for the mechanical behavior of bolted rock joints subjected to shearing[J]. Rock Mechanics and Rock Engineering，1996，29(2)：73–97.
[11] 刘泉声，雷广峰，彭星新，等. 节理岩体中锚杆剪切力学模型研究及试验验证[J]. 岩土工程学报，2018，40(5)：794–801.(LIU Quansheng，LEI Guangfeng，PENG Xingxin，et al. Model research and experimental verification of bolt shear mechanics in jointed rock mass[J]. Chinese Journal of Geotechnical Engineering，2018，40(5)：794–801.(in Chinese))
[12] 黎海滨，谭捍华，袁 维，等. 剪切方向与锚杆倾向垂直条件下锚杆的锚固机制研究[J]. 应用力学学报，2021，38(5)：1 995–2 003. (LI Haibin，TAN Hanhua，YUAN Wei，et al. Research on the anchorage mechanism of the bolt under the condition that the shear direction and the inclination of the bolt are perpendicular[J]. Chinese Journal of Applied Mechanics，2021，38(5)：1 995–2 003.(in Chinese))
[13] 李育宗，刘才华. 拉剪作用下节理岩体锚固力学分析模型[J]. 岩石力学与工程学报，2016，35(12)：2 471–2 478.(LI Yuzong，LIU Caihua. Anchorage mechanics analysis model of jointed rock mass under tension-shear action[J]. Chinese Journal of Rock Mechanics and Engineering，2016，35(12)：2 471–2 478.(in Chinese))
[14] HOLMBERG M. The mechanical behavior of untensioned grouted rock bolts[Ph. D. Thesis][D]. Stockholm：Royal Institute of Technology，1991.
[15] DIGHT P M. Improvements to the stability of rock walls to open pit mines[Ph. D. Thesis][D]. Melbom：Monash University，1982.
[16] 王发玲，刘才华，龚 哲. 顺层岩质边坡锚杆支护机制研究[J]. 岩石力学与工程学报，2014，33(7)：1 465–1 470.(WANG Faling，LIU Caihua，GONG Zhe. Study on the bolt support mechanism of bedding rock slope[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(7)：1 465–1 470.(in Chinese))
[17] 陈文强，贾志欣，赵宇飞，等. 剪切过程中锚杆的轴向和横向作用分析[J]. 岩土力学，2015，36(1)：143–148.(CHEN Wenqiang，JIA Zhixin，ZHAO Yufei，et al. Analysis of axial and lateral action of bolt during shearing[J]. Rock and Soil Mechanics，2015，36(1)：143–148.(in Chinese))
[18] 杨步云，肖 明，罗 宁，等. 锚杆剪切过程中的受力机理分析[J].华中科技大学学报：自然科学版，2019，47(3)：127–132.(YANG Buyun，XIAO Ming，LUO Ning，et al. Analysis of the stress mechanism during the shearing process of the bolt[J]. Journal of Huazhong University of Science and Technology：Natural Science，2019，47(3)：127–132.(in Chinese))
[19] 葛修润，刘建武. 加锚节理面抗剪性能研究[J]. 岩土工程学报，1988，10(1)：8–19.(GE Xiurun，LIU Jianwu. Study on shear performance of anchored joint surfaces[J]. Chinese Journal of Geotechnical Engineering，1988，10(1)：8–19.(in Chinese))
[20] 杨延毅. 加锚层状岩体的变形破坏过程与加固效果分析模型[J]. 岩石力学与工程学报，1994，13(4)：309–317.(YANG Yanyi. Deformation failure process and reinforcement effect analysis model of anchored layered rock mass[J]. Chinese Journal of Rock Mechanics and Engineering，1994，13(4)：309–317.(in Chinese))
2023, Vol. 42 
