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An Insight into the Excavation-Induced Stress Paths on Mechanical Response of Weak Interlayer Zone in Underground Cavern Under High Geostress Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-19 Shu-Qian Duan, Quan Jiang, Guo-Feng Liu, Jie-Cheng Xiong, Po Gao, Ding-Ping Xu, Ming-Yu Li
A weak interlayer zone (WIZ) is a poor zonal geotechnical system with loose structure, weak mechanical properties, variable thickness, random distribution, and strong extension, that occurs between different rock strata (e.g., tuff and basalt), due to the intense tectonic movement, representing a potential threat to the overall stability of rock masses with WIZs in large underground cavern excavations
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Evolution Characteristics of Bulking Factor in the Multi-field Loading of Broken Coal: An Experimental Study Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-15 Xinlei Yang, Tingxiang Chu, Minggao Yu, Liang Wang, Jiangkun Chao, Xuefeng Han
From the perspective of spontaneous combustion control in coal mining, this study conducted a progressive axial loading test of broken coal using a self-designed multi-field coupling oxidation test system. The evolutionary characteristics of the bulking factor under different loading conditions of stress, stress–temperature, and stress–moisture were obtained. Subsequently, factors affecting the bulking
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Ultimate Bearing Capacity of Low-Density Volcanic Pyroclasts: Application to Shallow Foundations Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-11 Alcibiades Serrano, Rubén Galindo, Áurea Perucho
The present research focuses on the calculation of the bearing capacity of low-density volcanic Pyroclasts. First, the theoretical basis that define an adequate failure criterion for collapsible rocks based on the parameters that characterize them are developed here. Second, a mathematical characteristic lines method is proposed to resolve the ultimate load of shallow foundation rocks with collapsible
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Time Delay Mechanism of the Kaiser Effect in Sandstone Under Uniaxial Compressive Stress Conditions Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-10 Xiang Fu, Yu-Xin Ban, Qiang Xie, Rini Asnida Abdullah, Jun Duan
The rapid and accurate measurement of in situ stress fields is one of the essential steps in geological engineering. Indoor acoustic emission tests and the Kaiser effect provide a promising prior peak stress measurement method. This paper aims to qualitatively explore the time delay mechanism of the Kaiser effect under uniaxial compressive stress. Acoustic emission tests were conducted with natural
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Development of Anisotropy in Sandstone Subjected to Repeated Frost Action Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-10 Hailiang Jia, Shun Ding, Fan Zi, Guoyu Li, Yuan Yao
In cold regions, the anisotropy of sedimentary rocks is modified by repeated frost action, potentially increasing the risks of rock engineering. Hence, a deep understanding of the development of rock anisotropy due to frost action is essential. In this work, two sets of sandstone samples were cored and used in experiments, which contained bedding planes either perpendicular or parallel to the height
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A Simplified Model for Time-Dependent Deformation of Rock Joints Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-10 Mingzheng Wang, Ming Cai
Understanding the time-dependent deformation behavior of rock joint is important when evaluating long-term stability of structures built on or in jointed rock masses. This study focuses on the time-dependent strength and deformation of unweathered clean rock joints. First, five grain-scale joint models are established based on Barton’s standard joint profiles using the GBM-TtoF creep material model
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Effects of Elevated Temperatures on the Microstructural, Physico-Mechanical and Elastic Properties of Barakar Sandstone: A Study from One of the World’s Largest Underground Coalmine Fire Region, Jharia, India Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-10 Adarsh Tripathi, Noopur Gupta, Ashok Kumar Singh, Sarada P. Mohanty, Nachiketa Rai, Anindya Pain
Experimental investigations of the effects of elevated temperature on microstructural, mineralogical, physico-mechanical and elastic properties of rocks were carried out to understand the effect of underground coal fire along with thermal damage and failure initiation in Barakar sandstone from the Jharia coalfield, India. Discolouration analysis, petrographic studies, scanning electron microscopy,
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A DEM-Based Factor to Design Rock-Socketed Piles Considering Socket Roughness Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-10 J. G. Gutiérrez-Ch, S. Senent, S. Melentijevic, R. Jimenez
The Distinct Element Method (DEM) has gained recent attention to study geotechnical designs with rock-concrete or rock–rock interfaces, such as rock-socketed piles. In this work, 3D DEM models with non-standard contacts laws (the Smooth-Joint and Flat-Joint contact models) are proposed to analyze the response of axially loaded rock-socketed piles with different sockets roughness, since socket roughness
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Re-analysis of Abutment Angle Method for Moderate and Deep Cover Retreat Room and Pillar Mines and Investigation of Loading Mechanics Using Finite Volume Modeling Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-08 Deniz Tuncay, Ihsan Berk Tulu, Ted Klemetti
Mining-induced stresses in underground coal mines play a significant role in pillar and ground support design, hence in the safety of mining operations. In the US, Analysis of Longwall Pillar Stability (ALPS) and in Australia, Analysis of Longwall Tailgate Serviceability (ALTS) software are used for designing Longwall coal mine layouts; and in the US, Analysis of Retreat Mining Pillar Stability (ARMPS)
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Improvement of DDA with a New Unified Tensile Fracture Model for Rock Fragmentation and its Application on Dynamic Seismic Landslides Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-08 Mingyao Xia, Guangqi Chen, Pengcheng Yu, Xinyan Peng, Jinfeng Zou
Discontinuous deformation analysis (DDA) method is a discrete element method, presenting a great advantage in modelling deformation and rigid body movements, and it is also an alternative approach for problems involving the fracturing process from continuity to discontinuity if the failure mechanism in DDA is well constituted. This paper presents a new united tensile fracture model (UTFM) for the two-dimensional
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Prediction of Peak Shear Strength of Natural, Unfilled Rock Joints Accounting for Matedness Based on Measured Aperture Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-05 Francisco Ríos-Bayona, Fredrik Johansson, Diego Mas-Ivars
The mechanical behaviour of natural, unfilled rock joints is influenced by the interaction between surface roughness and matedness of the contact surfaces. In the field, natural rock joints normally exhibit a mismatch between the contact surfaces, mainly due to different geological processes such as weathering or deformations. Various attempts have been made to estimate how matedness of rock joints
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Impacts of Void Existence on Mechanical Behavior of Tuff-like Lithophysal Material Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-05 Omed S. Q. Yousif, Moses Karakouzian, Douglas B. Rigby
In the current literature, the existence of lithophysae can cause a substantial change in the mechanical properties of tuff rock. However, since the shapes and distributions of the lithophysae are typically irregular and random, exploring the influence of lithophysae existence on the engineering behavior of lithophysae-rich tuff rock using the actual samples is very challenging. Besides, it is almost
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Evaluation Method of Rock Brittleness under True Triaxial Stress States Based on Pre-peak Deformation Characteristic and Post-peak Energy Evolution Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-05 Yan Zhang, Xia-Ting Feng, Chengxiang Yang, Qiang Han, Zhaofeng Wang, Rui Kong
Deep rock masses are in true triaxial stress (TTS) fields, and few studies have examined the brittleness evaluation of rock under TTS thus far. In particular, research has not been conducted on the brittleness evaluation index and the effect of TTS. Therefore, based on a summary and analysis of pre-existing brittleness indexes, this paper proposes a brittleness index of rock under TTS that considers
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Nanoscale Coal Deformation and Alteration of Porosity and Pore Orientation Under Uniaxial Compression: An In Situ SANS Study Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-05 Rui Zhang, Shimin Liu
Nanoscale coal deformation affects the geomechanics response of coal structure under external stress conditions. In this study, in situ small-angle neutron scattering (SANS) is used to characterize the evolution of nanopore structures under uniaxial compression on an Illinois coal specimen. Porod invariant mapping is used to estimate apparent porosities at different azimuthal angles. Structure-free
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Analytical Solution for Deep Circular Tunnels in Rock with Consideration of Disturbed zone, 3D Strength and Large Strain Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-04 Haohua Chen, Hehua Zhu, Lianyang Zhang
This paper presents a new analytical solution for deep circular tunnels in rock with consideration of disturbed zone, 3D strength and large strain. The rock is assumed to be elastic–brittle–plastic and governed by a 3D Hoek–Brown yield criterion. To take the large displacement around a tunnel into account, the large-strain theory is adopted to determine the displacement of rock in the plastic zone
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Study on Time-Dependent Fracturing Behaviour for Three Different Hard Rock Under High True Triaxial Stress Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-04 Jun Zhao, Xia-Ting Feng, Chengxiang Yang, Yangyi Zhou, Yan Zhang
True triaxial short-term and long-term tests were conducted on three different types of hard rocks, namely, marble, basalt and granite. During true triaxial long-term creep tests, the crack evolution information was collected by using an acoustic emission system. The micro-structures before and after creep tests were analysed by scanning electron microscopy and polarising microscopy. The time-dependent
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Experimental Study on Anchorage Mechanical Behavior and Surface Cracking Characteristics of a Non-persistent Jointed Rock Mass Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-04 Sheng-Qi Yang, Miao Chen, Yan Tao
It is significant to conduct anchorage on the non-persistent jointed rock mass by bolts to inhabit the unstable fracture evolution of rock engineering. In this research, a series of experiments are done on 70 specimens to investigate the effect of anchorage method on strength and deformation behavior of a non-persistent jointed rock mass. First, based on the stress–strain curves of anchorage jointed
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Experimental Permeability Tensor for Fractured Carbonate Rocks Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-04 D. Cabrera, F. Samaniego
This paper presents a novel petrophysical experiment for measuring the 3D permeability tensor at reservoir conditions in fractured vuggy carbonate rock. The permeability variation with confining pressure is demonstrated through the experimental investigation; the permeability ellipse plots show the decrease of permeability, as a function of the increase in effective stress. The experiment was developed
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Rate Effect in Frictional Contact on Porous Rocks Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-03 Yaneng Zhou, George Z. Voyiadjis
The rate-dependent mechanism is analyzed for frictional contact between a blunt tool and a fluid-infiltrated porous rock under pressurized condition. The dimensional analysis is adopted to derive a dimensionless number \(\lambda\) that predominantly governs the rate-dependent mechanism from pore pressure diffusion. The governing nature of \(\lambda\) is analyzed by finite element modeling using the
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Performance and Reuse of Steel Shot in Abrasive Waterjet Cutting of Granite Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-03 Yohan Cha, Tae-Min Oh, Gun-Wook Joo, Gye-Chun Cho
Steel shots are suitable for abrasive waterjet rock cutting and recycling because of the high hardness and magnetic properties of steel. This study evaluated the rock-cutting performance and recycling characteristics of steel shot waterjet. The rock-cutting responses of steel shot and garnet were compared at the same waterjet conditions. The used steel shot was collected and the particle-size changes
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Experimental Study on Failure Behaviour of Ligaments Between Strike-Inconsistent Fissure Pairs Under Uniaxial Compression Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-03 Da Huang, Zidai Yan, Zhu Zhong, Shilin Luo, Duofeng Cen, Yixiang Song, Dongming Gu
Aiming at the fact that discontinuities in rock mass exhibit different orientations, uniaxial compression tests of resin specimens containing a strike-inconsistent fissure pair were carried out to investigate the failure behaviour of the ligaments. Combined with computerized tomography scanning technology, cracking behaviour and ligament failure pattern were revealed. The failure characteristics and
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Erosion Wear Characteristics of Rock Eroded Using Abrasive Air Jet at 90° Impingement Angle Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-03 Yong Liu, Jiaojiao Wu, Jianping Wei, Tianxuan Hao, Xiaotian Liu
An abrasive air jet, which is sufficiently powerful to break rock, has significant potential in the field of assisted rock breaking, such as assistive tunnel excavation using a tunnel boring machine. To make its application more efficient and beneficial, a clear and definite erosion mechanism of an abrasive air jet is necessary. However, the present erosion mechanisms of an abrasive air jet have mostly
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The Influence of Multiple Dynamic Loading on Fragmentation Characteristics in Dynamic Compression Tests Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Xing Li, Wei Yao, Chonglang Wang
Dynamic fragmentation is one of the primary fracture types for rock mass in rock engineering. The dynamic fragmentation process and dynamic fragment size characteristics are important for the fragmentation optimization in field. Most researchers studied the fragmentation forming process via dynamic compression test using the traditional split Hopkinson pressure bar (SHPB) system, in which the multiple
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Instability Mechanism of Pillar Burst in Asymmetric Mining Based on Cusp Catastrophe Model Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Xinrong Wang, Kai Guan, Tianhong Yang, Xige Liu
Pillars are often reserved asymmetrically in the mining process. The roof deflection curve under non-equal span conditions of adjacent stopes is derived by considering the roof-pillar system as a rock beam-pillar model. The pillar instability condition under asymmetric mining is determined based on instability theory and cusp catastrophe theory. Pillar burst represents the equilibrium stability of
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Pull-out and Critical Embedment Length of Grouted Rebar Rock Bolts-Mechanisms When Approaching and Reaching the Ultimate Load Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Are Håvard Høien, Charlie C. Li, Ning Zhang
Rock bolts are one of the main measures used to reinforce unstable blocks in a rock mass. The embedment length of fully grouted bolts in the stable and competent rock stratum behind the unstable rock blocks is an important parameter in determining overall bolt length. It is required that the bolt section in the stable stratum must be longer than the critical embedment length to ensure the bolt will
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Big Data Nanoindentation and Analytics Reveal the Multi-Staged, Progressively-Homogenized, Depth-Dependent Upscaling of Rocks’ Properties Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Shengmin Luo, Daeyoung Kim, Yongkang Wu, Yucheng Li, Dongfang Wang, Jinliang Song, Don J. DeGroot, Guoping Zhang
This paper presents a newly observed phenomenon of upscaling of rocks’ properties using big data nanoindentation and analytics involving Gaussian mixture modeling (GMM), leading to characterizing the cross-scale mechanical properties of four shales and one sandstone. A large number (i.e., ~ 500) of statistical indentation measurements to depths of 6–8 μm were performed on each rock, resulting in continuous
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Underground Rock Dissolution and Geomechanical Issues Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Farid Laouafa, Jianwei Guo, Michel Quintard
Many soluble rocks will dissolve when in contact with fluid such as water. This transformation of rock solid into flowing fluid may trigger the creation of cavities which may further lead to either smooth subsidence or sudden collapse of land surface. Dissolution phenomenon can be of natural or human origin. This paper deals with the problem of the dissolution of underground soluble rocks and the geomechanical
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A New Rock Brittleness Index Based on the Characteristics of Complete Stress–Strain Behaviors Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Zhihao Kuang, Shili Qiu, Shaojun Li, Shihui Du, Yong Huang, Xingqiang Chen
Rock brittleness is an essential mechanical property, which plays a significant role in rock classifications and rockburst risk evaluations. To overcome the problems associated with the traditional brittleness indexes not comprehensively charaterizing the rock strength and deformation behaviors, this study systematically summarized the existing rock brittleness indexes. Then, a novel brittleness index
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Analytical Stress Solutions for a Deep Buried Circular Tunnel Under an Unsteady Temperature Field Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Qian-xiang Cheng, Ai-zhong Lu, Chong-lin Yin
This paper proposes a method for solving the stress field of a deep circular tunnel affected by an unsteady temperature field. The tunnel is idealized as an infinite domain problem, and the solution of the unsteady temperature field can be regarded as solving the temperature field in the infinite domain under the first type of boundary conditions. The temperature field distribution inside the tunnel
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Experimental Investigation and Numerical Modeling of Coupled Elastoplastic Damage and Permeability of Saturated Hard Rock Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-02 Chaojun Jia, Sheng Zhang, Weiya Xu
The mechanical behavior and permeability evolution of saturated hard rock are significantly important to the stability and safety of super-high arch dams. A series of triaxial compression tests were conducted on amygdaloidal basalt under different pore pressures. Based on the experimental results, a micromechanical-based elastoplastic damage model is proposed for such saturated hard rock. The hydromechanical
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P-Wave Velocity Calculation (PVC) in Rock Mass Without Geophysical-Seismic Field Measurements Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2021-01-01 Mohammad Fathollahy, Ali Uromeiehy, Mohammad Ali Riahi, Yaghoob Zarei
Ultrasonic studies have been used as low-cost, quickly updated, non-destructive techniques in geology and geo-technique. Conventional geophysical operations that allow measurements of wave velocity in rock mass are costly. In this study, we sought a strategy for calculation of wave velocity in rock mass without these field operations. The velocity of a wave in rock mass is a function of two major factors:
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Correction to: Mechanical and Volumetric Fracturing Behaviour of Three‑Dimensional Printing Rock‑like Samples Under Dynamic Loading Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-12-01 Tao Zhou, Jianbo Zhu, ·Heping Xie
The article Mechanical and Volumetric Fracturing Behaviour of Three-Dimensional Printing Rock-like Samples.
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A Unified Constitutive Model for Rock Based on Newly Modified GZZ Criterion Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-19 Haohua Chen, Hehua Zhu, Lianyang Zhang
This paper proposes a unified constitutive model for rock based on the newly modified generalized Zhang-Zhu (GZZ) criterion. The constitutive model adopts a non-associated plastic flow rule and a continuous potential function that takes the three effective principal stresses into account. To reflect strain-softening, strain-hardening, and elastic-perfectly plastic behavior of rock in a unified way
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Three-Dimensional Crack Recognition by Unsupervised Machine Learning Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-18 Chunlai Wang, Xiaolin Hou, Yubo Liu
Many macrocracks are usually generated during the fracturing of rocks. Elucidating the spatial distribution of cracks provides the basis for understanding crack nucleation and fracture formation in rock mechanics. Considering either a single microcrack or all the microcracks provides a limited interpretation of rock mass failure that is often induced by different macrocracks. Here we recognize macrocracks
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Evaluation of Borehole Hydraulic Fracturing in Coal Seam Using the Microseismic Monitoring Method Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-17 Nan Li, Liulin Fang, Weichen Sun, Xin Zhang, Dong Chen
Accurate evaluation of the influence range of borehole hydraulic fracturing (HF) in coal seam is crucial for optimizing the design scheme of HF. In this study, we adopted the microseismic (MS) monitoring technology to monitor and characterize the spatial shape of cracks caused by borehole HF in coal seam in an underground coal mine. And we also tested and analyzed the stress and moisture content changes
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Fracture Initiation, Gas Ejection, and Strain Waves Measured on Specimen Surfaces in Model Rock Blasting Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-17 Zong-Xian Zhang, Li Yuan Chi, Yang Qiao, De-Feng Hou
Crack velocity, gas ejection, and stress waves play an important role in determining delay time, designing a blast and understanding the mechanism of rock fragmentation by blasting. In this paper, the emerging times of the earliest cracks and gas ejection on the lateral surfaces of cylindrical granite specimens with a diameter of 240 mm and a length of 300 mm were determined by high-speed photography
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Fracture Evolution and Energy Characteristics During Marble Failure Under Triaxial Fatigue Cyclic and Confining Pressure Unloading (FC-CPU) Conditions Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-13 Y. Wang, W. K. Feng, R. L. Hu, C. H. Li
This work aims at investigating the fracture evolution and energy characteristics of marble subjected to fatigue cyclic loading and confining pressure unloading (FC-CPU) conditions. Although rocks under separated fatigue cyclic loading and triaxial unloading conditions have been well studied, little is known about the dependence of the fatigue damage accumulation on the subsequent confining pressure
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Ground Saturation Response During First Filling of Lined Pressure Tunnels: A Case Study Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-12 Saeed Ahmad, Abdul Muntaqim Naji, Ijaz Hussain, Hafeezur Rehman, Hankyu Yoo
The Neelum–Jhelum Hydropower Project, commissioned in April 2018 and located in the Azad Kashmir region of northeast Pakistan, is one of the most challenging and technically complex projects in the region. The project’s 28.6 km headrace tunnels are constructed in a highly mountainous region with relatively complex geology that includes various sedimentary rocks of Murree formation. The hydro-mechanical
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Experimental Study on Rock Strength and Deformation Characteristics Under Triaxial Cyclic Loading and Unloading Conditions Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-11 Qing-bin Meng, Jiang-Feng Liu, Li Ren, Hai Pu, Yan-long Chen
The mechanical behavior of rock under cyclic loading is quite complicated compared to monotonic loading or unloading conditions. The triaxial cyclic loading and unloading testing of rock specimens under 6 confining pressures (σ3) was carried out through the MTS 815 rock mechanics testing system, to explore the strength, deformation, and expansion characteristics of the rock specimens. The stress–strain
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Study on the Triaxial Unloading Creep Mechanical Properties and Damage Constitutive Model of Red Sandstone Containing a Single Ice-Filled Flaw Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-10 Ren-liang Shan, Yao Bai, Yang Ju, Tian-yu Han, Hao-yu Dou, Zhao-long Li
The freezing method is an effective approach for constructing coal mine shafts through water-rich soft rock strata. The frozen wall produced by this technique stops the movement of water and offers temporary support, ensuring the safety and stability of the shaft working face. However, most frozen rock masses generally comprise ice-filled flaws and frozen intact rock. A frozen fissured rock mass undergoing
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Characterization of Anisotropic Fracture Properties of Silurian Longmaxi Shale Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-10 L. Ren, H. P. Xie, X. Sun, R. Zhang, C. B. Li, J. Xie, Z. T. Zhang
Fracking is widely applied to enhance shale gas mining, and insight into the fracture behaviors of shale rocks is important. To characterize the fracture properties of Lower Silurian Longmaxi shale, a chevron-notched deep beam specimen, which inherits the advantages of notched deep beam and chevron-notched specimens, is introduced, and several three-point bend tests were conducted on the Longmaxi shale
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A Novel True Triaxial Apparatus for Simulating Strain Bursts Under High Stress Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-07 Manchao He, Jieyu Li, Dongqiao Liu, Kai Ling, Fuqiang Ren
This paper introduces a new high-pressure servo true triaxial rockburst experimental apparatus that can realize multi-face rapid unloading in the horizontal direction. The apparatus is used to simulate different types of strain burst phenomena in deep underground engineering, such as those at roadways, roadway intersections, and pillars with three and four free faces. In the research and development
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Influence of Mineralogical and Micro-Structural Changes on the Physical and Strength Properties of Post-thermal-Treatment Clayey Rocks Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-05 Hakan Ersoy, Murat Karahan, Hasan Kolaylı, M. Oğuz Sünnetci
This study investigates the effects of thermal treatment and exposure time on the physico-mechanical properties related to the mineralogical and structural changes of clayey rocks at temperatures of up to 1000 °C. Vitric-crystal tuffs were studied because they show different engineering behavior than most rocks at high temperatures. The samples were heated at the rate of 10 °C/min, exposed to the desired
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Experimental Investigation of Spalling Failure of D-Shaped Tunnel Under Three-Dimensional High-Stress Conditions in Hard Rock Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-05 Xuefeng Si, Linqi Huang, Xibing Li, Chunde Ma, Fengqiang Gong
The D-shaped cross section is a commonly used tunnel cross section in underground engineering. To simulate the failure process of a D-shaped hole under deep three-dimensional (3D) high-stress conditions, true-triaxial tests were conducted on cubic granite specimens with a through D-shaped hole, and the failure process of the hole sidewall was recorded in real time. Results show that the spalling failure
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Fracture Propagation of Rock like Material with a Fluid-Infiltrated Pre-existing Flaw Under Uniaxial Compression Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-04 C. Wei, B. Zhang, W. Zhu, S. Wang, J. Li, ·L. Yang, C. Lin
Crack propagation can gradually reduce the strength of the rock and eventually result in rock failure. Coupling effect of stress and seepage in fracture could accelerate the rock failure process. In this work, a set of water sealing device is developed to apply different fluid pressures in the pre-existing fracture in specimens made of rock-like material. We have carried out uniaxial compression tests
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Anisotropic Wellbore Stability Analysis: Impact on Failure Prediction Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-03 Michinori Asaka, Rune Martin Holt
Shale formations are the main source of borehole stability problems during drilling operations. Suboptimal predictions of borehole failure may partly be caused by neglecting the anisotropic nature of shales: Conventional wellbore stability analysis is based on borehole stresses computed from isotropic linear elasticity (Kirsch solution) with the assumption of no induced pore pressure. This is very
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Three-Dimensional Numerical Modeling of Grain-Scale Mechanical Behavior of Sandstone Containing an Inclined Rough Joint Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-03 Jin-Zhou Tang, Sheng-Qi Yang, Derek Elsworth, Yan Tao
We intercompare highly constrained physical experiments with a three-dimensional bonded-particle discrete element model. The models incorporate a single inclined rough joint at various inclinations to simulate the mechanical response of fractured-rock from micro-scale cracking through crack-coalescence and culminating in macro-scale rupture. This approach combines the scanned 3D surface morphology
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Experimental Study on Damage and Fracture Characteristics of Beishan Granite Subjected to High-temperature Treatment with DIC and AE Techniques Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-11-02 Shuting Miao, Peng-Zhi Pan, Xingguang Zhao, Changyue Shao, Peiyang Yu
The effect of high temperatures up to 800 °C on the physical and mechanical characteristics and fracturing behaviour of Beishan granite is experimentally studied with a combination of acoustic emission (AE), digital image correlation (DIC) and optical microscope observations. The experimental results show that the responses of the P-wave velocity, the effective porosity, Young’s modulus, and the uniaxial
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Temperature-Induced Explosive Behaviour and Thermo-Chemical Damage on Pyrite-Bearing Limestones: Causes and Mechanisms Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-28 V. Martínez-Ibáñez, D. Benavente, C. Hidalgo Signes, R. Tomás, M. E. Garrido
In this investigation, two different varieties of ‘Prada’ limestones were studied: a dark grey texture, bearing quartz, clay minerals, organic matter and pyrites, and a light grey texture with little or no presence of such components. We have observed two effects of different intensity when heating the dark texture from 400 °C: (1) the explosion of certain samples and (2) greater thermal damage than
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Response of Upper Jurassic (Malm) Limestone to Temperature Change: Experimental Results on Rock Deformation and Permeability Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-27 Liang Pei, Guido Blöcher, Harald Milsch, Günter Zimmermann, Ingo Sass, Xiaochun Li, Ernst Huenges
The present study aimed to quantify the thermally induced deformation and the associated evolution of permeability in Blaubeuren limestone, an outcrop analogue of the Upper Jurassic (Malm) carbonate formation, providing references for hydro-thermo-mechanical responses of the reservoir rock to temperature changes within future enhanced geothermal systems as located in the Southern German Molasse Basin
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Drill Monitoring for Rock Mass Grouting: Case Study at the Stockholm Bypass Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-27 Jeroen van Eldert, Johan Funehag, Håkan Schunnesson, David Saiang
In tunneling, rock mass grouting is a method applied to reduce water ingress. Grouting is influenced by rock mass conditions, especially apertures, frequency, and continuation of fracturing. These rock mass conditions can partly be determined by rock mass classification systems. At the Stockholm bypass, the Measurement While Drilling (MWD) Fracturing Index was applied to characterize the rock mass
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Experimental Study on Strain Burst Characteristics of Sandstone Under True Triaxial Loading and Double Faces Unloading in One Direction Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-27 Manchao He, Fuqiang Ren, Dongqiao Liu, Shudong Zhang
In this study, a new strain burst test system was used to conduct two types of strain burst experiments by rapidly unloading single and double faces (in one direction), to simulate the strain burst occurring in surrounding rock of tunnel or double tunnel faces during the opposite tunneling. A high-speed image recording system and an acoustic emission system were used to monitor the failure process
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Experimental Study of Electric Potential Response Characteristics of Different Lithological Samples Subject to Uniaxial Loading Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-23 Zhonghui Li, Xin Zhang, Yang Wei, Muhammad Ali
Electric potential (EP) signals are detected when coal or rock materials are subjected to mechanical loading. Such signals are attributed to the generation and accumulation of free charges under externally applied loads. Due to the excellent correlation between EP and damage evolution, EP methods have great potential in rock mass structural engineering damage monitoring. To systematically study the
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Transversely Isotropic Poroelastic Behaviour of the Callovo-Oxfordian Claystone: A Set of Stress-Dependent Parameters Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-21 Philipp Braun, Siavash Ghabezloo, Pierre Delage, Jean Sulem, Nathalie Conil
In the framework of a deep geological radioactive waste disposal in France, the hydromechanical properties of the designated host rock, the Callovo-Oxfordian claystone (COx), are investigated in laboratory tests. Experiments presented in this study are carried out to determine several coefficients required within a transversely isotropic material model. They include isotropic compression tests, pore
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Thermo-Poro-Elastic Behaviour of a Transversely Isotropic Shale: Thermal Expansion and Pressurization Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-21 Philipp Braun, Siavash Ghabezloo, Pierre Delage, Jean Sulem, Nathalie Conil
The Callovo-Oxfordian (COx) claystone is considered as a candidate host rock for a deep geological radioactive waste repository in France. Due to the exothermic waste packages, the rock is expected to be submitted to temperatures up to 90 °C. The temperature rise induces deformations of the host rock, together with an increase in pore pressures, involving complex thermo-hydro-mechanical (THM) couplings
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Permeability Evolution of Two-Dimensional Fracture Networks During Shear Under Constant Normal Stiffness Boundary Conditions Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-20 Bo Li, Ruyi Bao, Ye Wang, Richeng Liu, Cheng Zhao
The permeability evolution of fractal-based two-dimensional discrete fracture networks (DFNs) during shearing under constant normal stiffness (CNS) boundary conditions is numerically modeled and analyzed based on a fully coupled hydromechanical (HM) model. The effects of fractal dimension, boundary normal stiffness and hydraulic pressure on the evolutions of mechanical behaviors, aperture distributions
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Effects of Test Temperature and Low Temperature Thermal Cycling on the Dynamic Tensile Strength of Granitic Rocks Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-20 Ahmad Mardoukhi, Yousof Mardoukhi, Mikko Hokka, Veli-Tapani Kuokkala
This paper presents an experimental procedure for the characterization of the granitic rocks on a Mars-like environment. To gain a better understanding of the drilling conditions on Mars, the dynamic tensile behavior of the two granitic rocks was studied using the Brazilian disc test and a Split Hopkinson Pressure Bar. The room temperature tests were performed on the specimens, which had gone through
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Geomechanical characterisation of organic-rich calcareous shale using AFM and nanoindentation Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-19 S. P. Graham, M. Rouainia, A. C. Aplin, P. Cubillas, T. D. Fender, P. J. Armitage
The geomechanical integrity of shale overburden is a highly significant geological risk factor for a range of engineering and energy-related applications including CO\(_2\) storage and unconventional hydrocarbon production. This paper aims to provide a comprehensive set of high-quality nano- and micro-mechanical data on shale samples to better constrain the macroscopic mechanical properties that result
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Mechanical Properties of Acid-corroded Sandstone Under Uniaxial Compression Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-18 Shuguang Li, Yingming Wu, Runke Huo, Zhanping Song, Yoshiaki Fujii, Yanjun Shen
Long-term exposure to chemical solutions can change the mineral composition and microstructure and may seriously affect the physical and mechanical properties of rocks. Therefore, to clarify the effects of long-term exposure and types of acids on the mechanical properties of rocks, and to develop the constitutive model of acid-immersed rocks, uniaxial compression tests were carried out on acid-immersed
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A Limit Equilibrium Model of Tabular Mine Pillar Failure Rock Mech. Rock Eng. (IF 4.14) Pub Date : 2020-10-15 J. A. L. Napier, D. F. Malan
An improved understanding of pillar strength and pillar failure mechanisms is required to optimize tabular mine layout designs. The paper describes the application of a limit equilibrium model for pillar failure analysis. It is shown that the model is capable of reproducing a hardening or softening response for uniformly compressed strip or square pillars. The stress–strain behavior depends on three
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