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Challenges and Strategies for Sustainable Development in Deep Mines

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A special issue of Sustainability (ISSN 2071-1050).

Deadline for manuscript submissions: closed (23 August 2023) | Viewed by 14511

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Special Issue Editors

Dr. Fan Feng

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Guest Editor

College of Energy and Mining Engineering, Shandong University of Science and Technology, Qingdao 266590, China
Interests: testing and experiments on rock mechanical properties; mining method and ground pressure control in deep mines; rockburst mechanism and control techniques; FEM/DEM approach

Dr. Eryu Wang

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Guest Editor

School of Mining and Coal Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China
Interests: mining rock mechanics and engineering; mining pressure and strata control; non-pillar mining method and technology of coal mines; numerical simulation of rock failure in geotechnical engineering; physical modelling experiment of underground space

Dr. Ruifeng Huang

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Guest Editor

School of Emergency Technology and Management, North China Institute of Science and Technology, Langfang 065201, China
Interests: deep rock mechanics and engineering; gob-side entry retaining technique; mining pressure and strata control; prevention and control of coal mine gas disaster

Special Issue Information

Dear Colleagues,

The increasing demand for resources has led to the construction of a large number of mines at depth due to the exhaustion of reserves at shallow depths. The construction and operation of underground mining projects are highly related to the mechanical behavior of rock or coal materials in an in situ environment, which includes high geostress, water, temperature, discontinuities, etc. People working in a mine face a great number of biomechanical challenges in their engineering activities, such as rockbursts, mine earthquakes, underground space instability, water inrush, heat injury, gas explosions, dust explosions, and mine fires, obstructing sustainable development in deep mining engineering. Up to now, although great effort has been dedicated to interpreting the failure mechanism of engineering disasters induced by complex circumstances, it is still difficult to accurately characterize, evaluate, and control these disasters in deep mines. Therefore, the investigation and better understanding of hazard challenges and control strategies of disasters is of key importance in the scientific design and safe operation of deep mining engineering. This Special Issue is dedicated as a specific platform for studies on deep mine disasters using laboratory tests, numerical simulation, theoretical analysis and field application. This topical section can serve as the missing link between applied and fundamental research journals. Therefore, “Challenges and Strategies for Sustainable Development in Deep Mines” is devoted to, and thus welcomes, all mine disaster-based scientific research in order to deepen the understanding of disaster mechanisms and sustainable control in deep mining engineering. Authors are therefore invited to submit their relevant research contributions to this Special Issue in the form of reviews, research articles, and technical notes.

Dr. Fan Feng
Dr. Eryu Wang
Dr. Ruifeng Huang
Guest Editors

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Keywords

deep mine disaster mechanism
underground space instability
disaster monitoring and warning
rockburst/coalburst mechanism
water inrush and groundwater flow
gas and dust explosion
sustainable development theory in deep mine
disaster control techniques
engineering application
numerical simulation

Published Papers (13 papers)

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Research

15 pages, 3174 KiB

Open AccessArticle

Experimental and Numerical Study of Water–Rock Coupling Creep under Uniaxial Compression

by Feng Chen, Chengyu Miao, Ming Jiang and Xiaoming Sun

Sustainability 2023, 15(20), 14718; https://doi.org/10.3390/su152014718 - 10 Oct 2023

Viewed by 734

Abstract

In order to study the influence of the long-term strength of the rock surrounding deep roadways under the action of groundwater on surrounding rock stability, taking the rock surrounding the deep roadway of the Wanfu Coal Mine as the main research object, uniaxial compression and uniaxial creep tests were carried out on sandstone samples under different water-content states. It was found that the water content had an obvious softening effect on short-term and long-term strength, and both strengths showed a negative exponentially declining relationship. The viscosity modulus (

{\bar{E}}_{v}

) was put forward to describe viscoelastic creep deformation. And damage variables corresponding to E (the instantaneous elastic modulus) and

{\bar{E}}_{v}

were proposed. A sticky element that can describe the accelerated creep behavior was also established to improve the Nishihara model, based on the experimental results and damage theory. A comparison of the identified parameters and the experimental curves showed that the model can describe the mechanical behavior of various creep stages well. The model was developed using the ABAQUS user subroutine function, and the uniaxial compression creep experiment was simulated. The simulation results were basically consistent with the experimental results, which provide a basis for the further long-term stable use of roadway and creep failure simulation and have important practical and guiding significance. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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14 pages, 1594 KiB

Open AccessArticle

Analysis of Economic Benefits of Using Deep Geological Storage Technology to Treat High-Salinity Brine in Coal Mines

by Song Du, Chao Zhang, Jianguo Liu, Chunhui Zhang, Yinglin Fan, Qiaohui Che, Sitong Song and Sheng Tao

Sustainability 2023, 15(19), 14553; https://doi.org/10.3390/su151914553 - 7 Oct 2023

Viewed by 719

Abstract

Some provinces in China require zero discharge of coal mine wastewater, with a focus on the disposal of high-salt water, because evaporation ponds have been completely banned. Deep geological storage (DGS) technology is a novel geological environment solution that uses rock pores and microfissures within deep strata for safely storing liquid or gas to avoid its environmental impact on the biosphere. The author and his research team were the first to put forward the research idea of using DGS technology to dispose of high-salinity brine in coal mines in China and performed related research. Taking a coal mine in the south of Ordos Basin as an example, this study designed a conventional, mine-specific, zero-discharge water treatment process route based on a evaporation–crystallization process. This strategy was tailored to the unique water inflow conditions of the mine. Furthermore, the technical and economic efficiencies were assessed for the generation and treatment scenarios of a four-stage highly concentrated brine solution. In addition, the comparative analysis of the economic prospects of using DGS technology to treat high-salinity brine revealed that combining DGS with post-conventional treatment in secondary reverse osmosis, whose flow quality is 481 m³/h and TDS is 24,532.66 mg/L, can maximize the economic benefits. This integration heightened water resource utilization while maintaining a cost-effective, comprehensive water treatment approach. These results provide a valuable reference value for the future zero-discharge treatment of coal mine water. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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15 pages, 5579 KiB

Open AccessArticle

Investigating Disaster Mechanisms Triggered by Abrupt Overburden Fracture Alterations in Close-Seam Mining Beneath an Exceptionally Thick Sandstone Aquifer

by Tao Yan, Chuanqu Zhu, Qingfeng Li and Qian Xu

Sustainability 2023, 15(18), 13845; https://doi.org/10.3390/su151813845 - 18 Sep 2023

Cited by 2 | Viewed by 816

Abstract

The influx of roof water from exceptionally thick sandstone aquifers in northwestern China’s mining regions presents considerable challenges to the safety and productivity of coal mining operations. However, a significant gap in the literature persists concerning the underlying mechanisms. In this study, we investigated coal-seam mining beneath the exceptionally thick sandstone aquifer of the Zhiluo Formation at the Lingxin Coal Mine, utilizing this context as the basis for our engineering analysis. Our examination probed the hydrogeological and geomechanical mechanisms responsible for the abrupt alterations in overburden fractures and their catastrophic consequences during close-seam mining operations, employing research methodologies such as a theoretical analysis, fluid–structure-coupled simulation, and comparative evaluation. The study highlighted the intricate interplay between compressive-shear loads and the mechanics of hydraulic fracturing processes. The results revealed that in the absence of waterproof coal pillars, the downward mining of the L1614, L1615, and L1616 working faces led to the overlying rock’s water-conducting fractures reaching 204.9 m. This height was equivalent to 20 times the combined mining thickness of the three coal seams, impacting both the K3 and K4 aquifers. Conversely, when the water-resistant coal pillars were retained during the downward mining of the L1814, L1815, and L1816 working faces, the maximum height of the water-conducting fractures in the overlying rock was 103.5 m. This height was 10 times the combined mining thickness of the three coal seams, affecting only the K4 aquifer. Notably, vertical hydraulic fracturing was observed when the water pressure variation in the K3 aquifer exceeded 2–3 times its initial value. The water-conducting fracture zone was primarily characterized by the presence of “Type I-II” fractures, with the termination point of each fracture influenced by pressure and shear forces. Furthermore, we established a “fracture cracking and propagation model” and a “hydraulic fracturing-induced disaster model” based on the principles of fracture mechanics. We also provided formulas for calculating the cracking angles and extension heights of overburden fractures’ endpoints, which were derived from the maximum normal stress criterion. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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19 pages, 15934 KiB

Open AccessArticle

Numerical Analysis on the Influence of Joint Density on the Stability of Complex Jointed Roadway Surrounding Rock

by Wenhai Wang, Chaolei Wu, Yiming Yang, Xiaohan Peng, Lishuai Jiang and Yifeng Huang

Sustainability 2023, 15(18), 13561; https://doi.org/10.3390/su151813561 - 11 Sep 2023

Cited by 1 | Viewed by 641

Abstract

The random distribution of a complex joint network within a coal–rock mass has a significant weakening effect on its bearing capacity, making the surrounding rock of the roadway highly susceptible to instability and failure under the influence of in situ stress and mining-induced stress. This poses challenges in controlling the surrounding rock and seriously affects the normal production of mines. Consequently, it is imperative to conduct stability analysis on complex jointed roadway surrounding rock. Therefore, taking the transport roadway of Panel 11030 in the Zhaogu No. 2 Coal Mine as a case study, the microscopic contact parameters of particles and joint surfaces in each rock layer were calibrated through uniaxial compression and shear simulation tests using the particle flow simulation software PFC2D 5.0. Based on the calibrated microscopic contact parameters, a multilayered roadway surrounding rock model containing complex joints was established, and the joint density was quantified to analyze its effects on the displacement field, stress field, force chain field, and energy field of the roadway surrounding rock. The research findings indicate that as the distance to the sidewall decreases, the impact of joint density on the deformation of the surrounding rock of the roadway increases. The displacement of the roadway roof, floor, and sidewalls is affected differently by the joint density, predominantly contingent upon the properties of the rock mass. During the process of stress redistribution in the surrounding rock, the vertical stress of the roof and floor is released more intensively compared to the horizontal stress, while the horizontal stress of the sidewalls is released more intensively compared to the vertical stress. The increase in joint density leads to an increasing release rate of the surrounding rock stress, causing the load-bearing rock mass to transfer towards the deeper part. As the joint density increases, the force chain network gradually transitions from dense to sparse, resulting in a decrease in strong force chains and a decline in the bearing capacity of the surrounding rock, accompanied by an expansion in the range of force chain failure and deformation. With the continuous increase in joint density, the values of maximum released kinetic energy and residual released kinetic energy become larger. Once the joint density reaches a certain threshold, the kinetic energy stability zone consistently maintains a high energy level, indicating extreme instability in the roadway and sustained deformation. The results provide a valuable insight for analyzing the failure mechanism of complex jointed roadway surrounding rock and implementing corresponding support measures. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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16 pages, 12755 KiB

Open AccessArticle

Experimental Study on the Mechanical Characteristics of Thin-Bedded Rock Masses Due to Water-Absorption Softening and Structural Effects

by Huichen Xu, Chengyu Miao, Chengwei Zhao, Dong Wang and Xiaoming Sun

Sustainability 2023, 15(16), 12625; https://doi.org/10.3390/su151612625 - 21 Aug 2023

Viewed by 681

Abstract

The efficient exploitation of deep-buried resources and the penetration of deep tunnels are related to the sustainable development of energy and security, and the stability of the surrounding rock of deep-buried tunnels is an important issue to study. Therefore, the mechanical characteristics of thin-bedded rock masses due to water-absorption softening and structural effects were studied. The results show that the uniaxial compressive strength tends to decrease first and then increase with the rise in layer inclination, and an overall U-shaped distribution is presented. The water-absorption and softening mechanism of slate, which is a typical thin-bedded rock masses, involves water entering the slate along the weak surface of the layer. Then, the expansion of water absorption and the expansion perpendicular to the layer caused by the action of clay minerals causes cracks along the layer surface near the weak surface of the layer, which is macroscopically manifested as a decrease in strength. Through the single weak-surface theory, the layer-inclination range of 25–79° is determined for shear failure. The universal distinct element code can accurately and intuitively reflect the failure mode of rock samples affected by moisture content and structural effects. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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19 pages, 5604 KiB

Open AccessArticle

Digital Quantitative Study on Fracture Gas Storage Space for a Three-Layer Composite Residual Mining Area

by Guorui Feng, Weichao Fan, Zhen Li, Zhiwei Wang, Yidie Zhang, Yanqun Yang, Xiaohong Yang, Xiangming Zhang and Gan Feng

Sustainability 2023, 15(8), 6348; https://doi.org/10.3390/su15086348 - 7 Apr 2023

Viewed by 1209

Abstract

Quantifying the fracture gas storage space is the key to improving the coalbed methane (CBM) extraction efficiency in residual mining areas (RMAs). In this paper, a new digital quantitative description method of fractures is proposed when using a digital image correlation (DIC) system to monitor strata displacement, which improves the accuracy of fracture statistical data. The results show that with the evolution of RMA from single to three layers, the rock strata area with displacement greater than 3.5 mm increases radially and the maximum fracture rate of the uppermost RMA increases by 64.26%. The fracture rate increases exponentially from top to bottom in a long-distance composite RMA and distributes parabolically in the horizontal partition. The area with the highest average fracture rate (12.65%) in the close-distance composite RMA is defined as the concentrated growth area. The longitudinal fracture rate of a cross-layer fracture area in the three-layer RMA exceeds 60%. The cross-layer fracture area connecting the composite RMA at the open-cut side is a favorable extraction location for surface drilling. The research results will provide theoretical support for the safe and sustainable exploitation of CBM and residual coal in composite RMA. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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12 pages, 4862 KiB

Open AccessArticle

Large-Deformation Failure Mechanism and Stability Control of a Swelling Soft Rock Roadway in a Sea Area: A Case Study in Eastern China

by Ling Dong, Dong Wang, Xiaoming Sun, Yujing Jiang, Hengjie Luan, Huichen Xu, Baocheng Li and Feng Cai

Sustainability 2023, 15(6), 5323; https://doi.org/10.3390/su15065323 - 17 Mar 2023

Cited by 3 | Viewed by 1008

Abstract

Coal mining in sea areas has higher requirements for geological support systems, technical equipment levels, and safety production capacities because of the complex engineering geological conditions of underwater coal mines. In this paper, the deformation failure mechanism and stability control of a typical swelling soft rock roadway in the Beizao coal mine in a sea area are studied. A series of mechanical experiments and theoretical analyses were conducted to research the mechanical properties and reasons for the deformation failure of the swelling soft rock roadway. The type of the large-deformation failure mechanism of the soft rock roadway was identified as type III_ABC, which could be converted to a simple one, such as type II_B. The proposed stability control measure, containing constant-resistance large-deformation bolts, steel mesh, floor hollow grouting cables, and steel fiber concrete, was applied to the site. A good supporting effect was achieved, which could provide a beneficial reference for swelling soft rock roadways in sea areas. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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15 pages, 4571 KiB

Open AccessArticle

Influence of Base-Angle Bolt Support Parameters and Different Sections on Overall Stability of a Roadway under a Deeply Buried High Stress Environment Based on Numerical Simulation

by Qinzheng Wu, Huanxin Liu, Bing Dai, Li Cheng, Danli Li and Penghui Qin

Sustainability 2023, 15(3), 2496; https://doi.org/10.3390/su15032496 - 30 Jan 2023

Cited by 5 | Viewed by 1137

Abstract

Strengthening the base-angle of a roadway can have a beneficial impact on its overall stability, but the specific optimal parameter selection range is still unclear. Fast Lagrangian Analysis of Continua 3D (FLAC3D) software is used to carry out the stability analysis of 5 kinds of roadway models with different section shapes under the conditions of no support and different base-angle bolt support angles, and the simulation verification is carried out under the actual working conditions of the Sanshandao Gold Mine. The conclusion is as follows: without support, the self-stability of a tri-centric arch roadway is the best, and that of a rectangular roadway is the worst. When the base-angle bolt dip angle is between 15° and 45°, a better supporting effect can be obtained under the established 5 kinds of roadway sections. In the straight wall circular arch roadway of the Sanshandao Gold Mine, the roadway stability is the best when the angle of the base-angle bolt is 15°. However, changing the length of the base-angle bolt, even if the length of the base-angle bolt is increased to a certain extent, will decrease the overall supporting effect of the supporting structure. This paper can provide a reference for the selection of tunnel bottom corner bolt support parameters. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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26 pages, 19261 KiB

Open AccessArticle

Research on Coal Mine Goaf Restoration Based on Stability of Overlying Rocks and Numerical Simulation Analysis: A Case Study of Jingmen Garden Expo Park

by Zaicheng Xu, Wei Xu, Peng Zhou, Zhenhua Zhu, Junyi Zhao and Peng Gao

Sustainability 2023, 15(2), 1464; https://doi.org/10.3390/su15021464 - 12 Jan 2023

Cited by 2 | Viewed by 1266

Abstract

Goaf restoration is an important part of urban space management. With mining of coal resources, appearance of goaf and subsidence areas causes serious geological disasters and environmental and ecological problems, which significantly affect urban safety, development, and construction. Therefore, repair of goafs is crucial. In this study, the goaf of Jingmen Garden Expo Park was taken as an example. Through acquisition of engineering geological condition parameters and data on the goaf combined with the mechanical parameters selected for the site, the deformation mechanism of the overlying strata of the goaf was analyzed, and a numerical model of the goaf was established. On this basis, FLAC(3D) was used for numerical simulation to evaluate the stability of the goaf; the suitability of the site was evaluated and divided, and the ecological restoration model of the goaf in Jingmen Garden Expo Park was studied. The results showed that different degrees of ecological restoration and construction of various facilities and buildings could be carried out in the goaf. Based on the varying degrees of stability in the goaf, an appropriate restoration path is suggested according to the suitability of these different degrees. The green, innovative, and sustainable restoration design of the goaf can be carried out according to these restoration paths in order to establish a green ecological system in Jingmen Garden Expo Park. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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11 pages, 1885 KiB

Open AccessArticle

Application of a Combined FEM/DEM Approach for Teaching a Deep Rock Mass Mechanics Course

by Fan Feng, Zhiwei Xie, Tianxi Xue, Eryu Wang, Ruifeng Huang, Xuelong Li and Shixian Gao

Sustainability 2023, 15(2), 937; https://doi.org/10.3390/su15020937 - 4 Jan 2023

Cited by 5 | Viewed by 1559

Abstract

Deep rock mass mechanics is a professional course which is offered to undergraduate and postgraduate students in some mining universities. This course mainly includes the following topics: the geological structure of deep rock mass, the mechanical properties of deep rocks, the strength theory of deep rock masses, stability analysis and control of deep surrounding rock classification of engineering rock masses, and the application of deep rock mechanics in underground mining engineering The purpose of this course is to present students with a basic theoretical knowledge of deep rock mass engineering. Analyzing the limitations of traditional deep rock mass mechanics teaching methods, here, we propose integrating a combined FEM/DEM (Finite Element Method/Discrete Element Method) approach into the teaching of a course on deep rock mass mechanics. The mechanical behaviors and failure instability process of rock at laboratory and engineering scales were analyzed using ELFEN software (a finite/discrete element code). The results show that a combined FEM/DEM approach as a deep rock mass mechanics teaching method is completely feasible and reasonable; this approach has the advantages of strong intuition, high reliability, time and labor savings, and low cost, which can offset the shortcomings of traditional teaching methods. Moreover, the proposed approach can stimulate students’ interests in a mining course on deep rock mass mechanics, deepen students’ understanding of the course curriculum, and cultivate students’ innovative abilities and subjective initiatives. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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15 pages, 2563 KiB

Open AccessArticle

Study on Height Prediction of Water Flowing Fractured Zone in Deep Mines Based on Weka Platform

by Liyang Bai, Changlong Liao, Changxiang Wang, Meng Zhang, Fanbao Meng, Mingjin Fan and Baoliang Zhang

Sustainability 2023, 15(1), 737; https://doi.org/10.3390/su15010737 - 31 Dec 2022

Cited by 1 | Viewed by 1373

Abstract

Accurately predicting the height of water flowing fractured zone is of great significance to coal mine safety mining. In recent years, most mines in China have entered deep mining. Aiming at the problem that it is difficult to accurately predict the height of water flowing fractured zone under the condition of large mining depth, the mining depth, height mining, inclined length of working face and coefficient of hard rock lithology ratio are selected as the main influencing factors of the height of water flowing fractured zone. The relationship between various factors and the height of water flowing fractured zone is analyzed by SPSS software. Based on the data mining tool Weka platform, Bayesian classifier, artificial neural network and support vector machine model are used to mine and analyze the measured data of water flowing fractured zone, and the detailed accuracy, confusion matrix and node error rate are compared. The results show that, the accuracy rate of instance classification of the three models is greater than 60%. The accuracy of the artificial neural network model is the highest and the node error rate is the lowest. In general, the training effect of the artificial neural network model is the best. By predicting engineering examples, the prediction accuracy of the model reaches 80%, and a good prediction effect is obtained. The height prediction system of water flowing fractured zone is developed based on VB language, which can provide a reference for the prediction of the height failure grade of water flowing fractured zone. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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15 pages, 5583 KiB

Open AccessArticle

Mechanical Properties and Energy Characteristics of Flawed Samples with Two Non-Parallel Flaws under Uniaxial Compression

by Qun Li, Changfu Huang, Yanbo Zhang, Peng Liang, Xulong Yao and Guangyuan Yu

Sustainability 2023, 15(1), 459; https://doi.org/10.3390/su15010459 - 27 Dec 2022

Viewed by 874

Abstract

Unequal flaws are widespread in rock engineering, in which the extensions induced by excavation and unloading are the main factors leading to engineering instability. Rock deformation and failure are essentially the results of energy transmission. In order to study the influence of flaw type and angle on the mechanical properties and energy characteristics of the flawed rock mass, uniaxial compression tests were conducted using particle flow numerical analysis software. The results show that the crack initiation strength and peak strength of the sample increase with the increase in the flaw angle. For smaller flaw angles, the sample shows obvious plastic deformation during uniaxial compression. For larger flaw angles, the sample shows elastic–brittle properties, whose storage energy is larger. The peak strength of samples with flaws of unequal length presents an obvious decrease compared with that of flawed samples with flaws of equal length, and the extent of the reduction is 6.15% on average. Unequal flaws decrease the ability of the flawed sample to absorb strain energy. Compared with flawed samples with equal flaws, flawed samples with unequal flaws decrease the boundary energy and elastic strain energy by 9.29% and 9.95% on average, respectively. Flaws of unequal length in this sample can weaken the performance of the flawed sample. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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16 pages, 20759 KiB

Open AccessArticle

Experimental Study on Deformation Characteristics of Gangue Backfill Zone under the Condition of Natural Water in Deep Mines

by Yao Lu, Ning Jiang, Wei Lu, Meng Zhang, Dezhi Kong, Mengtang Xu and Changxiang Wang

Sustainability 2022, 14(23), 15517; https://doi.org/10.3390/su142315517 - 22 Nov 2022

Cited by 4 | Viewed by 878

Abstract

To address the problem of surface subsidence caused by the compression of filling gangue in deep mines, a layered compaction test was designed based on the zonation of the failure of the overburden in the goaf and layered property of the filling gangue. The deformation characteristics of filling gangue in natural and water-bearing states were obtained. The deformation of filling gangue during the 0~100 kN loading stage was an approximately positive S-type, which reflects the relative “advancement” in terms of deformation. The filling gangue deformation in the 100~500 kN loading stage was an approximately inverted S-type, which reflects the relative “lag” in terms of deformation. In a natural state, the load-time curves of the dead load stage were consistent. Under a water-bearing condition, the load-time curve for the dead load stage had apparent “step” characteristics and presented a special phenomenon of displacement rebound. Under gradient loading, the strain showed an exponential growth model, and energy dissipation showed a logarithmic growth model. Under a natural state, the energy dissipation showed consistently increasing distribution patterns, while the energy dissipation showed a normal distribution model under the water-bearing state. Full article

(This article belongs to the Special Issue Challenges and Strategies for Sustainable Development in Deep Mines)

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