Compressive deformations and energy dissipation characteristics of broken rock masses under lateral confinement

Authors

TIAN Yu, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaFollow
LIN Haifei, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi’an 710054, ChinaFollow
LI Shugang, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi’an 710054, China
SHUANG Haiqing, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi’an 710054, China
XU Peiyun, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi’an 710054, China
LIU Sibo, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
JI Pengfei, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China
CUI Mingwei, College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, China

Abstract

Objective This study aims to investigate the deformation and energy dissipation characteristics of broken rock masses in the caving zones of goafs during compression and to reveal their impacts on the movement and failure of overlying strata and surface subsidence. Using a self-developed experimental system, this study conducted compression experiments on broken rock masses under lateral confinement under different Talbot index values and axial stresses. Then, it analyzed variations in axial displacement, void ratio, relative breakage index, fractal dimension, and strain energy density of the broken rock masses during compression. Accordingly, this study quantified variation patterns of strain energy density with axial strain and relative breakage index and revealed the influential mechanisms of axial stress and Talbot index on compressive deformation evolution of broken rock masses. Results and Conclusions The results indicate that with the increasing Talbot index and axial stress, the axial displacement and relative breakage index of the broken rock masses increased, while the void ratio decreased. Based on the nonlinear load-bearing characteristics of the broken rock masses, the compression process was divided into three stages: void compaction stage (σ<4 MPa), breaking and filling stage (4 MPa ≤ σ<6 MPa), and stable consolidation stage (σ≥6 MPa). With an increase in the axial stress, the fractal dimension of samples with different Talbot index values increased, albeit with a gradually decreasing growth rate. In contrast, under the same axial stress, the fractal dimension of samples showed a monotonic decrease with an increase in the Talbot index, significantly corresponding to the compression process. Moreover, the broken rock masses presented increasing strain energy density with an increase in the axial strain and relative breakage index. In contrast, under identical axial strain or relative breakage index, a higher Talbot index value corresponded to lower strain energy density. During the initial loading stage, the broken rock masses showed slight differences in strain energy density under the same axial strain, with the differences gradually increasing as loading progressed. The results of this study can provide a theoretical basis for the safety management of coal mine goafs and the prediction of surface subsidence.

Keywords

broken rock mass, compressive deformation, Talbot index, relative breakage index, strain energy density

DOI

10.12363/issn.1001-1986.25.03.0167

Recommended Citation

TIAN Yu, LIN Haifei, LI Shugang, et al. (2025) "Compressive deformations and energy dissipation characteristics of broken rock masses under lateral confinement," Coal Geology & Exploration: Vol. 53: Iss. 10, Article 59.
DOI: 10.12363/issn.1001-1986.25.03.0167
Available at: https://cge.researchcommons.org/journal/vol53/iss10/59

Reference

[1] 钱鸣高，许家林，王家臣，等. 矿山压力与岩层控制(第3版)[M]. 徐州：中国矿业大学出版社，2021.

[2] PENG Kang，ZHOU Jiaqi，ZOU Quanle，et al. Deformation characteristics of sandstones during cyclic loading and unloading with varying lower limits of stress under different confining pressures[J]. International Journal of Fatigue，2019，127：82−100.

[3] LOUPASAKIS C，ANGELITSA V，ROZOS D，et al. Mining geohazards–land subsidence caused by the dewatering of opencast coal mines：The case study of the Amyntaio coal mine，Florina，Greece[J]. Natural Hazards，2014，70(1)：675−691.

[4] 李振，余奕睿，王红伟，等. 承压破碎无烟煤气体渗透特性影响因素实验研究[J]. 煤田地质与勘探，2024，52(3)：1−13.

LI Zhen，YU Yirui，WANG Hongwei，et al. An experimental study of factors influencing gas seepage in confined broken anthracite[J]. Coal Geology & Exploration，2024，52(3)：1−13.

[5] 张村，赵毅鑫，屠世浩，等. 颗粒粒径对采空区破碎煤体压实破碎特征影响机制[J]. 煤炭学报，2020，45(增刊2)：660−670.

ZHANG Cun，ZHAO Yixin，TU Shihao，et al. Influence mechanism of particle size on the compaction and breakage characteristics of broken coal mass in goaf[J]. Journal of China Coal Society，2020，45(Sup.2)：660−670.

[6] 缪协兴，茅献彪，胡光伟，等. 岩石(煤)的碎胀与压实特性研究[J]. 实验力学，1997，12(3)：394−400.

MIAO Xiexing，MAO Xianbiao，HU Guangwei，et al. Research on broken expand and press solid characteristics of rocks and coals[J]. Journal of Experimental Mechanics，1997，12(3)：394−400.

[7] 冯梅梅，吴疆宇，陈占清，等. 连续级配饱和破碎岩石压实特性试验研究[J]. 煤炭学报，2016，41(9)：2195−2202.

FENG Meimei，WU Jiangyu，CHEN Zhanqing，et al. Experimental study on the compaction of saturated broken rock of continuous gradation[J]. Journal of China Coal Society，2016，41(9)：2195−2202.

[8] 李磊，卢守青，褚廷湘，等. 承压破碎煤体应变和孔渗演化机制与模型研究[J]. 煤田地质与勘探，2024，52(5)：37−45.

LI Lei，LU Shouqing，CHU Tingxiang，et al. Evolutionary mechanisms and models of strain，porosity，and permeability of compacted broken coals[J]. Coal Geology & Exploration，2024，52(5)：37−45.

[9] 温蓬，郭文兵，白二虎，等. 采空区不同岩性破碎岩石压实变形及声发射特征研究[J]. 采矿与安全工程学报，2024，41(2)：384−394.

WEN Peng，GUO Wenbing，BAI Erhu，et al. Compaction deformation and acoustic emission characteristics of fractured rock with different lithology in goaf[J]. Journal of Mining & Safety Engineering，2024，41(2)：384−394.

[10] 李巍，黄艳利，高华东，等. 不同级配矸石侧限压缩过程声发射特征研究[J]. 采矿与安全工程学报，2020，37(1)：155−161.

LI Wei，HUANG Yanli，GAO Huadong，et al. Study on acoustic emission characteristics of gangue of different graduations during confined compression[J]. Journal of Mining & Safety Engineering，2020，37(1)：155−161.

[11] 何淑欣，杨科，何祥，等. 正态分布矸石侧限压缩特征与声发射特征研究[J]. 地下空间与工程学报，2024，20(3)：827−837.

HE Shuxin，YANG Ke，HE Xiang，et al. Study on confined compression characteristics and acoustic emission characteristics of gangue with normal distribution[J]. Chinese Journal of Underground Space and Engineering，2024，20(3)：827−837.

[12] 杨科，魏祯，何祥，等. 矸石集料承载力学特性模拟研究[J]. 煤炭学报，2022，47(3)：1087−1097.

YANG Ke，WEI Zhen，HE Xiang，et al. Simulation experiment on bearing mechanical properties of gangue aggregate[J]. Journal of China Coal Society，2022，47(3)：1087−1097.

[13] 张俊文，王海龙，陈绍杰，等. 大粒径破碎岩石承压变形特性[J]. 煤炭学报，2018，43(4)：1000−1007.

ZHANG Junwen，WANG Hailong，CHEN Shaojie，et al. Bearing deformation characteristics of large–size broken rock[J]. Journal of China Coal Society，2018，43(4)：1000−1007.

[14] 张天军，陈佳伟，包若羽，等. 不同浸水时间级配破碎煤样的粒度分布分形特征[J]. 采矿与安全工程学报，2018，35(3)：598−604.

ZHANG Tianjun，CHEN Jiawei，BAO Ruoyu，et al. Fractal characteristics of particle size distribution of broken coal samples with different immersion time[J]. Journal of Mining & Safety Engineering，2018，35(3)：598−604.

[15] 张天军，刘楠，庞明坤，等. 级配破碎煤岩体压实过程中再破碎特征研究[J]. 采矿与安全工程学报，2021，38(2)：380−387.

ZHANG Tianjun，LIU Nan，PANG Mingkun，et al. Re–crushing characteristics in the compaction process of graded crushed coal rock mass[J]. Journal of Mining & Safety Engineering，2021，38(2)：380−387.

[16] 李伟，钟艺，郭敬杰，等. 不同类型煤颗粒侧限压缩变形破碎特性试验研究[J]. 煤炭科学技术，2022，50(2)：163−170.

LI Wei，ZHONG Yi，GUO Jingjie，et al. Experimental study on confined compression deformation and breakage characteristics for different types of coal particles[J]. Coal Science and Technology，2022，50(2)：163−170.

[17] 孙亚楠，张培森，颜伟，等. 采空区破碎砂岩承压变形特性试验研究[J]. 煤炭科学技术，2019，47(12)：56−61.

SUN Yanan，ZHANG Peisen，YAN Wei，et al. Experimental study on pressure–bearing deformation characteristics of crushed sandstone in gob[J]. Coal Science and Technology，2019，47(12)：56−61.

[18] 王兆会，刘鹏举，孙文超，等. 破碎煤岩压缩变形与再承载力学特性研究[J]. 采矿与安全工程学报，2023，40(3)：599−610.

WANG Zhaohui，LIU Pengju，SUN Wenchao，et al. Study on the compressive deformation and load–bearing capacity of broken blocks of coal and rock[J]. Journal of Mining & Safety Engineering，2023，40(3)：599−610.

[19] 陈晓祥，苏承东，唐旭，等. 饱水对煤层顶板碎石压实特征影响的试验研究[J]. 岩石力学与工程学报，2014，33(增刊1)：3318−3326.

CHEN Xiaoxiang，SU Chengdong，TANG Xu，et al. Experimental study of effect of water–saturated state on compaction property of crushed stone from coal seam roof[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(Sup.1)：3318−3326.

[20] 孙文斌，田殿金，马诚，等. 侧限条件下断层破碎岩体变形及渗流侵蚀特性[J]. 煤田地质与勘探，2025，53(1)：193−203.

SUN Wenbin，TIAN Dianjin，MA Cheng，et al. Deformations and seepage–induced erosion of fractured rocks in fault under confined settings[J]. Coal Geology & Exploration，2025，53(1)：193−203.

[21] 褚廷湘，李品，晁江坤，等. 承压破碎煤体碎胀系数演变特征与机制[J]. 煤炭学报，2017，42(12)：3182−3188.

CHU Tingxiang，LI Pin，CHAO Jiangkun，et al. Bulking coefficient evolution characteristics and mechanism of compacted broken coal[J]. Journal of China Coal Society，2017，42(12)：3182−3188.

[22] 苏承东，顾明，唐旭，等. 煤层顶板破碎岩石压实特征的试验研究[J]. 岩石力学与工程学报，2012，31(1)：18−26.

SU Chengdong，GU Ming，TANG Xu，et al. Experiment study of compaction characteristics of crushed stones from coal seam roof[J]. Chinese Journal of Rock Mechanics and Engineering，2012，31(1)：18−26.

[23] 张遵国，袁新立，陈毅，等. 不同应力循环路径下砂岩的能量演化特征[J]. 中国安全科学学报，2024，34(2)：144−152.

ZHANG Zunguo，YUAN Xinli，CHEN Yi，et al. Energy evolution characteristics of sandstone under different stress cycle paths[J]. China Safety Science Journal，2024，34(2)：144−152.

[24] 谢和平，鞠杨，黎立云. 基于能量耗散与释放原理的岩石强度与整体破坏准则[J]. 岩石力学与工程学报，2005，24(17)：3003−3010.

XIE Heping，JU Yang，LI Liyun. Criteria for strength and structural failure of rocks based on energy dissipation and energy release principles[J]. Chinese Journal of Rock Mechanics and Engineering，2005，24(17)：3003−3010.

[25] ZHOU Nan，HAN Xiaole，ZHANG Jixiong，et al. Compressive deformation and energy dissipation of crushed coal gangue[J]. Powder Technology，2016，297：220−228.

[26] 郁邦永，陈占清，戴玉伟，等. 饱和破碎砂岩压实过程中粒度分布及能量耗散[J]. 采矿与安全工程学报，2018，35(1)：197−204.

YU Bangyong，CHEN Zhanqing，DAI Yuwei，et al. Particle size distribution and energy dissipation of saturated crushed sandstone under compaction[J]. Journal of Mining & Safety Engineering，2018，35(1)：197−204.

[27] LI Meng，ZHANG Jixiong，ZHOU Nan，et al. Effect of particle size on the energy evolution of crushed waste rock in coal mines[J]. Rock Mechanics and Rock Engineering，2017，50(5)：1347−1354.

[28] 孟凡非，浦海，倪宏阳，等. 关闭矿井采空区破碎岩体再断裂机制及空隙结构演化特性[J]. 煤炭科学技术，2024，52(2)：104−114.

MENG Fanfei，PU Hai，NI Hongyang，et al. Research on re–fracturing mechanism and cavity structure evolution characteristics of broken rock mass in goaf of closed mine[J]. Coal Science and Technology，2024，52(2)：104−114.

[29] 徐培耘. 煤层高强开采卸压瓦斯运储区联动演化机理及其应用[D]. 西安：西安科技大学，2022.

XU Peiyun. Research on linkage evolution mechanism and application of pressure–relief gas transportation and storage area in high–intensity mining[D]. Xi’an：Xi’an University of Science and Technology，2022.

[30] 王海龙，王琦，赵振华，等. 采空区冒落矸石承压变形特征及侧向压力分布规律研究[J]. 煤炭科学技术，2023，51(6)：20−29.

WANG Hailong，WANG Qi，ZHAO Zhenhua，et al. Study on bearing deformation characteristics and lateral pressure distribution law of caved gangue in gob[J]. Coal Science and Technology，2023，51(6)：20−29.

[31] 郁邦永，陈占清，吴疆宇，等. 饱和级配破碎泥岩压实与粒度分布分形特征试验研究[J]. 岩土力学，2016，37(7)：1887−1894.

YU Bangyong，CHEN Zhanqing，WU Jiangyu，et al. Experimental study of compaction and fractal properties of grain size distribution of saturated crushed mudstone with different gradations[J]. Rock and Soil Mechanics，2016，37(7)：1887−1894.

[32] HARDIN B O. Crushing of soil particles[J]. Journal of Geotechnical Engineering，1985，111(10)：1177−1192.

[33] 郁邦永，潘书才，魏建军，等. 承压饱和破碎岩石颗粒破碎及渗透率演化特征研究[J]. 采矿与安全工程学报，2020，37(3)：632−638.

YU Bangyong，PAN Shucai，WEI Jianjun，et al. Particle crushing and permeability evolution of saturated broken rock under compaction[J]. Journal of Mining & Safety Engineering，2020，37(3)：632−638.

[34] WANG Luzhen，YIN Minggan，KONG Hailing，et al. Experimental study on breakage characteristics and energy dissipation of the crushed rock grains[J]. KSCE Journal of Civil Engineering，2022，26(3)：1465−1478.