Study on mesoscopic failure characteristics of layered red shale

Authors

MA Zhenqian, School of Mining, Guizhou University, Guiyang 550025, ChinaFollow
ZHOU Lang, School of Mining, Guizhou University, Guiyang 550025, ChinaFollow
ZUO Yujun, School of Mining, Guizhou University, Guiyang 550025, China
ZHANG Jimin, School of Mining, Guizhou University, Guiyang 550025, China
ZOU Yihuai, School of Mining, Guizhou University, Guiyang 550025, China
CAO Yunqin, School of Mining, Guizhou University, Guiyang 550025, China

Abstract

To study the mesoscopic failure characteristics of the layered red shale, uniaxial mechanical experiments were carried out by applying DSTD-1000 electro-hydraulic servo rigid pressure on the red shale with different bedding angles. Meanwhile, SEM and XRD experiments were implemented on debris to obtain its mechanical parameters, failure characteristics, microstructure, and relative content of components. Based on this, models of the red shale with different bedding angles were constructed using the discrete element PFC^3D for the uniaxial compression experiments to study the mesoscopic failure characteristics of red shale. The results show that: (1) When the bedding angle θ=30°, 45°, 60° and 75°, the samples fail along the bedding direction to produce a slip surface. (2) The crack evolution process of samples with different bedding angles shows the changes in the slow growth stage, accelerated growth stage, and stable stage. When θ=45°, 60° and 75°, more cracks are generated in the unit strain in the crack evolution process, which leads to the rapid slip failure of the sample along the weak plane of the bedding. (3) The stereographic projection of meso-cracks and the rock fabric diagram show that: the micro-cracks tend to be more evenly distributed, mainly parallel to or sub-parallel to the loading direction when θ=0°, 75° and 90°, showing strong anisotropy after loading failure. When 15°≤θ≤60°, the micro-crack tendency gradually parallels to the bedding direction. (4) The crack initiation stress threshold solved by the elastic modulus method considering the crack evolution characteristics is 36.6%‒60.3% of the peak strength of each bedding, and the crack damage stress threshold is 75.1%‒90.4% of the peak strength of each bedding, which is consistent with the threshold range obtained by a large number of physical experiments. It is indicated that the method has certain applicability for solution of the crack stress threshold.

Keywords

red shale, mesoscopic failure, stereographic projection, rock fabric, crack initiation stress, crack damage stress

DOI

10.12363/issn.1001-1986.23.01.0034

Recommended Citation

MA Zhenqian, ZHOU Lang, ZUO Yujun, et al. (2023) "Study on mesoscopic failure characteristics of layered red shale," Coal Geology & Exploration: Vol. 51: Iss. 10, Article 12.
DOI: 10.12363/issn.1001-1986.23.01.0034
Available at: https://cge.researchcommons.org/journal/vol51/iss10/12

Reference

[1] 黄书岭,钟鹏举,丁秀丽. 绿泥石片岩单轴压缩特征强度各向异性特征研究[J]. 岩石力学与工程学报,2021,40(增刊2):3182−3190.

HUANG Shuling,ZHONG Pengju,DING Xiuli,et al. Study on characteristic strength anisotropy of layered chlorite schist under uniaxial compression[J]. Chinese Journal of Rock Mechanics and Engineering,2021,40(Sup.2):3182−3190.

[2] 师文豪,杨天鸿,王培涛,等. 露天矿边坡岩体稳定性各向异性分析方法及工程应用[J]. 岩土工程学报,2014,36(10):1924−1933.

SHI Wenhao,YANG Tianhong,WANG Peitao,et al. Anisotropy analysis method for stability of open–pit slope rock mass and its application[J]. Chinese Journal of Geotechnical Engineering,2014,36(10):1924−1933.

[3] 师文豪,杨天鸿,于庆磊,等. 层状边坡各向异性岩体渗流–应力耦合模型及工程应用[J]. 岩土力学,2015,36(8):2352−2360.

SHI Wenhao,YANG Tianhong,YU Qinglei,et al. Seepage–stress coupling model of anisotropic rock mass of stratified slope and its engineering application[J]. Rock and Soil Mechanics,2015,36(8):2352−2360.

[4] KWAG S M,JUNG Y W,KIM G W. Engineering properties of red shale and black shale of the Daegu Area,Korea[J]. The Journal of Engineering Geology,2013,23(4):341−352.

[5] WANG Dongyi,LI Xibing,PENG Kang,et al. Geotechnical characterization of red shale and its indication for ground control in deep underground mining[J]. Journal of Central South University,2018,25(12):2979−2991.

[6] 李地元,莫秋喆,韩震宇. 干湿循环作用下红页岩静态力学特性研究[J]. 铁道科学与工程学报,2018,15(5):1171−1177.

LI Diyuan,MO Qiuzhe,HAN Zhenyu. Study on static mechanical properties of red shale under dry–wet circulation[J]. Journal of Railway Science and Engineering,2018,15(5):1171−1177.

[7] HE Manchao. Latest progress of soft rock mechanics and engineering in China[J]. Journal of Rock Mechanics and Geotechnical Engineering,2014,6(3):165−179.

[8] HADIZADEH J,LAW R D. Water–weakening of sandstone and quartzite deformed at various stress and strain rates[J]. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts,1991,28(5):431−439.

[9] 蒋长宝,陈昱霏,尹光志,等. 中间主应力与层理方向对页岩力学和渗透特性影响的试验研究[J]. 岩石力学与工程学报,2017,36(7):1570−1578.

JIANG Changbao,CHEN Yufei,YIN Guangzhi,et al. Experimental study on the effect of intermediate principal stress and bedding direction on mechanical properties and permeability of shale[J]. Chinese Journal of Rock Mechanics and Engineering,2017,36(7):1570−1578.

[10] 衡帅,杨春和,张保平,等. 页岩各向异性特征的试验研究[J]. 岩土力学,2015,36(3):609−616.

HENG Shuai,YANG Chunhe,ZHANG Baoping,et al. Experimental research on anisotropic properties of shale[J]. Rock and Soil Mechanics,2015,36(3):609−616.

[11] 吕有厂. 层理性页岩断裂韧性的加载速率效应试验研究[J]. 岩石力学与工程学报,2018,37(6):1359−1370.

LYU Youchang. Effect of bedding plane direction on fracture toughness of shale under different loading rates[J]. Chinese Journal of Rock Mechanics and Engineering,2018,37(6):1359−1370.

[12] 雷霆,夏磊,王秋良,等. 层状岩体的颗粒流模拟新方法及数值分析[J]. 科学技术与工程,2017,17(2):256−261.

LEI Ting,XIA Lei,WANG Qiuliang,et al. A new method to simulate the layered rock mass and the numerical analysis[J]. Science Technology and Engineering,2017,17(2):256−261.

[13] 杨圣奇,孙博文,田文岭. 不同层理页岩常规三轴压缩力学特性离散元模拟[J]. 工程科学学报,2022,44(3):430−439.

YANG Shengqi,SUN Bowen,TIAN Wenling. Discrete element simulation of the mechanical properties of shale with different bedding inclinations under conventional triaxial compression[J]. Chinese Journal of Engineering,2022,44(3):430−439.

[14] 邓荣贵,付小敏. 层状岩体力学特性模拟实验研究[J]. 实验力学,2011,26(6):721−729.

DENG Ronggui,FU Xiaomin. On the simulative experimental study of mechanical properties of stratified rock mass[J]. Journal of Experimental Mechanics,2011,26(6):721−729.

[15] SHANG Junlong,DUAN Kang,GUI Yan,et al. Numerical investigation of the direct tensile behaviour of laminated and transversely isotropic rocks containing incipient bedding planes with different strengths[J]. Computers and Geotechnics,2018,104:373−388.

[16] LIN Hang,CAO Ping,WANG Yixian. Numerical simulation of a layered rock under triaxial compression[J]. International Journal of Rock Mechanics and Mining Sciences,2013,60:12−18.

[17] BAHAADDINI M,SHARROCK G,HEBBLEWHITE B K. Numerical direct shear tests to model the shear behaviour of rock joints[J]. Computers and Geotechnics,2013,51:101−115.

[18] WANG Peitao,CAI Meifeng,REN Fenhua. Anisotropy and directionality of tensile behaviours of a jointed rock mass subjected to numerical Brazilian tests[J]. Tunnelling and Underground Space Technology,2018,73:139−153.

[19] CHEN Miao,YANG Shengqi,RANJITH P G,et al. Cracking behavior of rock containing non−persistent joints with various joints inclinations[J]. Theoretical and Applied Fracture Mechanics,2020,109:102701.

[20] XIA Kaiwen,REN Rui,LIU Feng. Numerical analysis of mechanical behavior of stratified rocks containing a single flaw by utilizing the particle flow code[J]. Engineering Analysis with Boundary Elements,2022,137:91−104.

[21] WU Shunchuan,XU Xueliang. A study of three intrinsic problems of the classic discrete element method using flat–joint model[J]. Rock Mechanics and Rock Engineering,2016,49(5):1813−1830.

[22] XIA Xiang,LI Hongbin,LI Jie,et al. A case study on rock damage prediction and control method for underground tunnels subjected to adjacent excavation blasting[J]. Tunnelling and Underground Space Technology,2013,35:1−7.

[23] ALCOTT J M,KAISER P K,SIMSER B P. Use of microseismic source parameters for rockburst hazard assessment[J]. Pure and Applied Geophysics,1998,153(1):41−65.

[24] EBERHARDT E,STEAD D,STIMPSON B,et al. Changes in acoustic event properties with progressive fracture damage[J]. International Journal of Rock Mechanics and Mining Sciences,1997,34(3/4):071B.

[25] DIEDERICHS M S,KAISER P K,EBERHARDT E. Damage initiation and propagation in hard rock during tunnelling and the influence of near–face stress rotation[J]. International Journal of Rock Mechanics and Mining Sciences,2004,41(5):785−812.

[26] DIEDERICHS M S. Manuel rocha medal recipient rock fracture and collapse under low confinement conditions[J]. Rock Mechanics and Rock Engineering,2003,36(5):339−381.

[27] TAHERI A,ZHANG Yubao,MUNOZ H. Performance of rock crack stress thresholds determination criteria and investigating strength and confining pressure effects[J]. Construction and Building Materials,2020,243:118263.

[28] MUNOZ H,TAHERI A,CHANDA E K. Fracture energy-based brittleness index development and brittleness quantification by pre-peak strength parameters in rock uniaxial compression[J]. Rock Mechanics & Rock Engineering,2016,49(12):4587−4606.

[29] WANG Yuanyuan,DENG Hucheng,DENG Yong,et al. Study on crack dynamic evolution and damage–fracture mechanism of rock with pre–existing cracks based on acoustic emission location[J]. Journal of Petroleum Science and Engineering,2021,201:108420.

[30] LI Xiaofeng,LI Haibo,LIU Lei,et al. Investigating the crack initiation and propagation mechanism in brittle rocks using grain−based finite−discrete element method[J]. International Journal of Rock Mechanics and Mining Sciences,2020,127:20.

[31] NICKSIAR M,MARTIN C D. Crack initiation stress in low porosity crystalline and sedimentary rocks[J]. Engineering Geology,2013,154:64−76.

[32] 王建良. 深埋大理岩力学特性研究及其工程应用[D]. 昆明：昆明理工大学，2012.

WANG Jianliang. Mechanical characteristics of deeply buried marble and its technical application[D]. Kunming：Kunming University of Science and Technology，2012.