Article
Computer Science, Interdisciplinary Applications
Yiguo Xue, Xudong Jiang, Fanmeng Kong, Zhiqiang Li, Huimin Gong, Fan Yang, Hong Chen
Summary: This study explores the characteristics of rock fragmentation in blasting scenarios for jointed rock mass of underground space by creating bonded particle models with discontinuities. The study found that different types of discontinuities have different effects on crack propagation and rock fragmentation.
SIMULATION MODELLING PRACTICE AND THEORY
(2022)
Article
Green & Sustainable Science & Technology
Weijian Yu, Hanxiao Guo, Ke Li, Bao Pan
Summary: The stability of damaged rock mass is crucial in underground engineering. Surface-fractured rock mass is a typical three-dimensional fracture, and the failure mechanism was studied through a mechanical model. Experimental studies were conducted on rock specimens with different depths of surface horizontal fissures. The results showed that the existence of horizontal joint plane significantly reduced the strength of the rock sample, and the depth of surface fissures played a role in controlling the failure mode. The surface crack sample exhibited regional asymmetric failure and poor structural stability.
Article
Energy & Fuels
Weiji Liu, Hai Hu, Xiaohua Zhu, Yunxu Luo, Mengqiu Chen
Summary: This research investigates the application of plasma channel drilling (PCD) technology in the exploitation of hot dry rock (HDR) geothermal resources, and reveals that PCD has the advantages of high rock-breaking efficiency and ROP. The study shows that increasing temperature on the plasma channel does not alter the trend of crack initiation and propagation, but only reduces the time consumption of crack initiation. The research also includes an experimental program to examine the granite fragmentation and borehole generation caused by an electrode bit. The results can provide new ideas and methods for improving the drilling efficiency of HDR formation and help to design the structural of drill bits based on PCD technology.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Geochemistry & Geophysics
Donghao Lan, Hongjian Deng, Yanan Gao, Yunlong Wang, Guangkai Zhang
Summary: In this paper, the rock fragmentation and crack propagation induced by tunnel boring machine (TBM) tunneling in anisotropic rock are studied. The study reveals the four stages of rock fragmentation and provides insights into the influence of indentation depth, angle of lateral cracks, and intrusion velocity on the process.
JOURNAL OF GEOPHYSICS AND ENGINEERING
(2022)
Article
Engineering, Geological
Jun Peng, Ming Cai, Zhijun Wu, Quansheng Liu, Chuanhua Xu
Summary: This study examines the crack initiation stress (CI) as an important indicator for thermally damaged rock under uniaxial compression. Different methods for determining CI are reviewed and compared. The results show that the CVS method and CAEH method provide comparable CI values, while the LSR method generally gives lower values. A modified LSR method is proposed to accurately determine CI for thermally damaged rocks. The study also reveals that CI generally decreases with increasing thermal damage.
ENGINEERING GEOLOGY
(2023)
Article
Metallurgy & Metallurgical Engineering
Fan Xiang, Yang Zhi-jun, Hong Ming, Yu Hao, Xie Yong-li
Summary: The complexity of rock mass structure can lead to uncertainties and risks in underground engineering construction. This study investigated laboratory tests on fractured rock-like materials containing a tunnel and established two-dimensional particle flow models. The results showed that the dip angle combination of preexisting fractures directly affects the stress, strain distribution, and failure characteristics around the tunnel. The findings provide theoretical support for the design of tunnel supporting structures.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2022)
Article
Energy & Fuels
Hao Xianjie, Wei Yingnan, Yang Ke, Su Jian, Sun Yingfeng, Zhu Guangpei, Wang Shaohua, Chen Haibo, Sun Zhuowen
Summary: The study reveals significant anisotropic characteristics in coal reservoirs, with compressive strength decreasing with increasing bedding angle. Crack initiation strength and damage strength show a decreasing-then-increasing trend with variations in bedding angle.
PETROLEUM EXPLORATION AND DEVELOPMENT
(2021)
Article
Computer Science, Interdisciplinary Applications
Chao Zhang, Jianxin Fu, Yu Wang
Summary: The authors aimed to study the strength failure and cracking behavior of fractured rock under unilateral unloading. They found that prefabricated cracks and unilateral unloading conditions not only deteriorate the mechanical strength but also have significant differences in failure modes. Furthermore, the authors discovered that the model failure mode under unilateral loading conditions is obviously distinct from that in triaxial loading.
ENGINEERING COMPUTATIONS
(2023)
Article
Engineering, Mechanical
Binxu Wang, Tingchun Li, Qingwen Zhu, Jinlin Ran, Yiteng Du, Hao Zhang
Summary: As geotechnical engineering extends to deeper formations, the creep behavior of surrounding rock becomes more significant. In this study, triaxial compression tests and triaxial creep tests are conducted to understand the creep deformation and creep propagation of fissured rocks. The experimental results show that fissured sandstone has a time-dependent failure mode and creep loading changes the crack behavior and produces more secondary cracks. The damage bond model effectively simulates the creep deformation and crack propagation process of sandstone, providing insights into the mechanisms of catastrophic events caused by damage evolution.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Green & Sustainable Science & Technology
Yanbin Zhang, Huazhong Yu, Huanchun Zhu, Yongsheng Zhu
Summary: This study investigates the excavation damage characteristics of surrounding rock in deeply buried marble tunnels in Jinping, China. Acoustic detection and simulation using the PFC2D program were used to analyze the damage zones and depth of the surrounding rock, revealing that the damage zones are unevenly distributed and increase with the buried depth and decrease in rock quality.
Article
Engineering, Geological
Rongchao Xu, Shengzhe Zhang, Zhen Li, Xinming Yan
Summary: The study examines the influence of strain rate on the crack stress threshold in different types of rocks and reveals the mechanical mechanism of hard rocks exhibiting different strength and deformation characteristics at various strain rates. The findings show that the strain rate has a significantly different effect on the damage stress level of different rock types. The strain characteristics of granite and sandstone are mainly influenced by the unstable crack propagation stage, with higher strain rates leading to more pronounced volumetric dilatation. The research results have important implications for engineering excavation.
Article
Multidisciplinary Sciences
Yao Bai, Haoyu Dou, Peng Sun, Tiancheng Ma, Yujing Wang, Yuqin Wang
Summary: Understanding the tensile strength properties and damage evolution mechanism in fissured rock is crucial for fundamental research and engineering design. This study investigates the effects of flaw dip angle on the tensile strength and crack propagation of rock-like materials. A parallel bonding model is proposed to examine the damage of pre-flawed discs. The results show that the flaw weakens the strength of the discs, and the failure modes are categorized into three types.
Article
Engineering, Mechanical
Danilo Rangel, Diego Erena, Jesus Vazquez, J. A. Araujo
Summary: This paper proposes a method to calculate fretting fatigue crack initiation and total life using iterative models calibrated with fatigue stress-strain-life curves, taking into account multiaxial non-proportional stress fields in fretting problems and stress gradient effects. The crack initiation path is obtained through the SWT parameter, and the analyzed results are validated by comparison with tests for an Aluminium 7075-T651 alloy in a cylindrical-flat configuration.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Civil
Jaspreet Singh, Sarada Prasad Pradhan, Vikram Vishal, Mahendra Singh
Summary: Rock mass heterogeneity due to structural discontinuities poses a significant concern to transportation. Characterizing the rock mass is crucial for preliminary investigation, with the Geological Strength Index (GSI) being a commonly used method. Advances in computational techniques, such as discrete fracture network (DFN) modeling and remote sensing, provide more precise data for examining rock mass characteristics. This work focuses on incorporating DFN in estimating GSI and utilizes machine learning to digitize the standard GSI chart.
TRANSPORTATION GEOTECHNICS
(2023)
Article
Energy & Fuels
Xia Zhong, Jiangbo Xu, Haohui Sun, Xinmin Hou, Faquan Wu, Peng Sha
Summary: This study thoroughly investigates the indirect tensile strength and damage mechanism of granite from the Yueyang area under different temperatures and loading rates. The findings suggest that the tensile strength of granite is directly proportional to the loading rate and inversely proportional to the temperature. Furthermore, temperature has a significantly greater impact on tensile strength compared to the loading rate, and is more likely to lead to the occurrence of secondary tensile cracks.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Engineering, Geological
Navid Bahrani, Benoit Valley, Peter K. Kaiser
CANADIAN GEOTECHNICAL JOURNAL
(2019)
Article
Engineering, Geological
Hannes Krietsch, Valentin Gischig, Keith Evans, Joseph Doetsch, Nathan Oliver Dutler, Benoit Valley, Florian Amann
ROCK MECHANICS AND ROCK ENGINEERING
(2019)
Article
Engineering, Geological
Mohammad Javad Afshari Moein, Benoit Valley, Keith F. Evans
ROCK MECHANICS AND ROCK ENGINEERING
(2019)
Article
Geochemistry & Geophysics
Maria Kakurina, Yves Guglielmi, Christophe Nussbaum, Benoit Valley
Article
Engineering, Geological
Benoit Valley, Keith F. Evans
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2019)
Article
Energy & Fuels
Valentin S. Gischig, Domenico Giardini, Florian Amann, Marian Hertrich, Hannes Krietsch, Simon Loew, Hansruedi Maurer, Linus Villiger, Stefan Wiemer, Falko Bethmann, Bernard Brixel, Joseph Doetsch, Nima Gholizadeh Doonechaly, Thomas Driesner, Nathan Dutler, Keith F. Evans, Mohammadreza Jalali, David Jordan, Anniina Kittila, Xiaodong Ma, Peter Meier, Morteza Nejati, Anne Obermann, Katrin Plenkers, Martin O. Saar, Alexis Shakas, Benoit Valley
GEOMECHANICS FOR ENERGY AND THE ENVIRONMENT
(2020)
Article
Multidisciplinary Sciences
Clement Roques, Ulrich W. Weber, Bernard Brixel, Hannes Krietsch, Nathan Dutler, Matthias S. Brennwald, Linus Villiger, Joseph Doetsch, Mohammadreza Jalali, Valentin Gischig, Florian Amann, Benoit Valley, Maria Klepikova, Rolf Kipfer
SCIENTIFIC REPORTS
(2020)
Article
Engineering, Geological
Maria Kakurina, Yves Guglielmi, Christophe Nussbaum, Benoit Valley
ROCK MECHANICS AND ROCK ENGINEERING
(2020)
Article
Geosciences, Multidisciplinary
N. O. Dutler, B. Valley, F. Amann, M. Jalali, L. Villiger, H. Krietsch, V. Gischig, J. Doetsch, D. Giardini
Summary: The study shows that high-pressure fluid injections can cause pore pressure changes and potentially induce seismic activity. The experiments reveal that, in contrast to near-field responses, far-field responses are due to effective stress changes in the anisotropic stress field.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Geological
Asmae Dahrabou, Benoit Valley, Peter Meier, Philip Brunner, Andres Alcolea
Summary: Deep geothermal boreholes often encounter borehole breakouts, which compromise the stability and performance of drilling. This study presents a systematic methodology to evaluate stress distributions, rock strength, and their interactions, and applies it to a real borehole data set in Basel, Switzerland.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Engineering, Geological
Mohammad Javad Afshari Moein, Keith F. Evans, Benoit Valley, Kristian Bar, Albert Genter
Summary: The scaling laws describing the spatial arrangement of fractures along six deep boreholes in the Rhine Graben were studied. It was found that the arrangement of fractures followed fractal behavior at all scales from meters to several hundred meters, with the fractal dimensions ranging from 0.85 to 0.9. However, a significant deviation from fractal behavior was observed in the core dataset, which could be attributed to the presence of a localized zone. The results have implications for the parameterization of discrete fracture network models in deep rock masses.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Geochemistry & Geophysics
Laure Duboeuf, Louis De Barros, Maria Kakurina, Yves Guglielmi, Frederic Cappa, Benoit Valley
Summary: Experimental observations show that seismic activity occurs on existing natural fractures and bedding planes during fluid injections, with significant local stress perturbations. Moreover, stress perturbations induced by aseismic deformation dominate the triggering of seismic activity.
GEOPHYSICAL JOURNAL INTERNATIONAL
(2021)
Article
Engineering, Geological
Nathan Dutler, Benoit Valley, Valentin Gischig, Mohammadreza Jalali, Bernard Brixel, Hannes Krietsch, Clement Roques, Florian Amann
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2020)
Article
Geochemistry & Geophysics
Hannes Krietsch, Valentin S. Gischig, Joseph Doetsch, Keith F. Evans, Linus Villiger, Mohammadreza Jalali, Benoit Valley, Simon Low, Florian Amann
Article
Geochemistry & Geophysics
Linus Villiger, Valentin Gischig, Joseph Doetsch, Hannes Krietsch, Nathan Dutler, Mohammadreza Jalali, Benoit Valley, Paul A. Selvadurai, Arnaud Mignan, Katrin Plenkers, Domenico Giardini, Florian Amann, Stefan Wiemer
