首页|Experimental study on unloading induced shear performances of 3D saw-tooth rock fractures

Experimental study on unloading induced shear performances of 3D saw-tooth rock fractures

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
  • 维普
A fractal model governing saw-tooth fractures was first introduced to replicate sandstone samples con-taining an inclined 3D penetrating rough fracture surface with various joint roughness coefficients (JRC). In conventional triaxial compression, the peak strength for fractured samples increased with both confin-ing pressure and JRC. During the unloading confining pressure process, the normal stress of fractures declined but the shear stress increased, resulting in shear sliding of fractures. The shear displacement of fractures exponentially increased, and the positive normal displacement decreased gradually to nega-tive values under coupling effects of shear contraction caused by normal stress and shear dilation due to climbing effects of fractures. Transition from quasi-static to dynamic sliding of the fractures was identi-fied. The sliding resistance duration increased with confining pressure but decreased with JRC. After pre-peak unloading, the fracture surfaces presented a more significant surface wear response and JRC values decreased by 1.70％–59.20％due to more remarkable asperity degradation compared with those after con-ventional triaxial compression. The theoretical model for shear strength of fractures was established through improving the Ladanyi&Archambault model by introducing the relations between normal stress and surface wear ratios of fractures, which agreed well with the experimental results.

Saw-tooth fracture surfacesPre-peak unloadingShear slidingNormal displacementJRC values

Qian Yin、Xinxin Nie、Jiangyu Wu、Qi Wang、Kaiqi Bian、Hongwen Jing

展开 >

State Key Laboratory for Geomechanics&Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China

State Key Laboratory of High Performance Civil Engineering Materials,Jiangsu Research Institute of Building Science Co.,Ltd.,Nanjing 210008,China

Department of Materials,University of Oxford,Oxford OX13PH,UK

State Key Laboratory for Geomechanics&Deep Underground Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China

展开 >

National Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaNatural Science Foundation of Jiangsu Province,ChinaNatural Science Foundation of Jiangsu Province,ChinaFundamental Research Funds for the Central Universities,ChinaXuzhou Science and Technology Project,ChinaXuzhou Science and Technology Project,ChinaYunlong Lake Laboratory of Deep Underground Science and Engineering Project,China

52174092519042905200427252274145BK20220157BK202006602022YCPY0202KC21033KC22005104023002

2023

矿业科学技术学报(英文版)
中国矿业大学

矿业科学技术学报(英文版)

CSTPCDCSCD北大核心EI
影响因子：1.222
ISSN：2095-2686
年,卷(期)：2023.33(4)
  • 2
  • 8