Article
Engineering, Geological
Lie Kong, Pathegama Gamage Ranjith, Bing Qiuyi Li
Summary: This paper proposes a coupled hydro-grain-based discrete element model to explore fluid-driven micro-cracking of crystalline rock. Laboratory-scale fracturing cases over granite are simulated, revealing unique behaviors such as non-symmetrical propagation, zipper mode initiation, and generations of cracks. The cracking mode is dominated by tension failure, with variations in crack orientation and aperture influenced by in-situ stresses.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Review
Cell Biology
Manuela A. Boos, Shireen R. Lamande, Kathryn S. Stok
Summary: The transfer of stress and strain signals between the extracellular matrix (ECM) and cells plays a crucial role in tissue morphogenesis, growth, and homeostasis. In cartilage tissue, the spatial variation of ECM molecules leads to nonuniform strain transfer, impacting the forces sensed by cells. However, the influence of these nonuniform forces on cartilage health and integrity is not fully understood. Understanding the multiscale strain transfer and structure-function relationships in cartilage is essential for comprehending cellular responses and tissue remodeling.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2022)
Article
Computer Science, Interdisciplinary Applications
Yang Ye, Yawu Zeng, Xi Chen, Hanqing Sun, Wenjun Ma, Zhixiong Peng
Summary: Research on the normal restitution coefficient in practical rockfall trajectory analysis emphasized the size and velocity dependences, resulting in the development of a new impact device and proposed contact model. The study found that the size and rate-dependent strength significantly affect the NCOR, with size having a greater influence than impact velocity.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Mechanics
Mengli Li, Jianfa Wu, Junfeng Li, Li Zhuang, Shanyong Wang, Fengshou Zhang
Summary: This paper develops a numerical model combining a grain-based discrete element model (DEM) and a pore network model to study the interaction behavior between hydraulic fractures and the inherent microstructures of rocks. The results show that fracture propagation driven by supercritical carbon dioxide tends to be less smooth, more asymmetric, and tortuous compared to high viscosity fluid. Additionally, the strength of intergranular bonding and the average grain size play a role in determining the dominant type of fractures (intergranular or intragranular). Weak grains can result in more intragranular fractures and fewer intergranular fractures. The study highlights the complex fracture propagation caused by low-viscosity fracturing fluid and strong micro heterogeneity of microstructures.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Geological
Louis Ngai Yuen Wong, Yahui Zhang, Xin Cui, Zhijun Wu
Summary: Rock strength typically decreases at temperatures above 400 degrees C, but a study on Sichuan Marble found that its strength actually increased in the temperature range of 25-200 degrees C. To understand this thermal strengthening phenomenon, a grain-based model (thermo-GBM) was proposed, and experiments were conducted to calibrate and verify the model. The results showed that microstructural heterogeneity played a significant role in the thermal strengthening effect, and thermal expansion and degradation of grain-boundary properties were the governing mechanisms.
Article
Engineering, Multidisciplinary
X. F. Li, H. B. Li, J. Zhao
Summary: This study aims to understand the effects of micro-heterogeneity on the initiation, propagation, and coalescence of microcracks in rocks. The research reveals that grain size, morphology, and mineralogy play significant roles in determining the mechanical properties of rocks, such as crack initiation stress and compression strength.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Computer Science, Interdisciplinary Applications
Shirui Zhang, Wenfang Xiao, Weiwei Jia
Summary: Understanding the failure process of brittle rocks at both macroscopic and microscopic levels is important for predicting their strength and deformation characteristics. However, studying the evolution of microcracks in these rocks is challenging due to their heterogeneity. In this study, a multiscale grain-based model was developed based on FDEM to simulate the behavior of brittle rocks at the grain scale. The model considered the actual grain size, inter-grain and intra-grain contacts, as well as local polycrystal inclusions and internal cleavage. Simulated tests, including uniaxial tensile and compression tests, were conducted based on laboratory data. The results showed that the transgranular fracture capacity played a crucial role in mesoscopic fracture simulation, and the difference in inter-grain and intra-grain tensile strength controlled the failure mechanism of rock samples under uniaxial compression. The ability of minerals to absorb elastic strain energy significantly influenced the path of microcracks and the transition from tension to shear failure mechanisms. The findings of this study provide insights into the microcrack evolution mechanism in heterogeneous rocks and a method for comprehensive analysis of crack propagation and energy evolution.
SIMULATION MODELLING PRACTICE AND THEORY
(2023)
Article
Engineering, Environmental
Hailong Zhang, Yang Tang, Ting Ren, Seisuke Okubo, Shoujian Peng
Summary: The behaviors of four types of rocks in generalized stress relaxation tests were analyzed, and a method for calculating the generalized relaxation compliance (GRC) was proposed. The results showed that GRC is time-dependent and related to the type of rock and stress level.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2022)
Article
Engineering, Geological
Gen Li, Yi Zhao, Lihua Hu, Shengtao Qi, Chunan Tang
Summary: This study introduces a local multiscale high-resolution modeling strategy that can save computational cost effectively in rock fracturing process and avoid calculation waste in local fracturing. The simulation results are consistent with global uniform mesh modeling and physical tests. The combination of the SMDMM and LMHM is shown to be an efficient strategy for modeling the transscale progressive failure process of rock.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Materials Science, Ceramics
Mi Wang, Xiaobin Chen, Guoqing Xie, Lingling Wang, Zhaosheng Yu, Fengdong Wang
Summary: This study proposes a discrete element method to investigate the dynamic compression behaviors of ZrB2-SiC ceramic. By simulating experiments and calibrating parameters, the compressive stress-strain curve and micro-damage evolution law of ZrB2-SiC ceramic are obtained. The results show that the damage evolution and crack behavior of ZrB2-SiC ceramic exhibit significant strain-rate dependence under dynamic compression.
INTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Jie Zhang, Xu Wu
Summary: This study investigates the damage evolution of cracked rock under repeated impact loading through impact tests and proposes macroscopic damage variables considering geometric and mechanical parameters. A constitutive model based on the coupling damage is developed to describe the progressive damage characteristics of cracked rock masses.
Article
Mathematics, Interdisciplinary Applications
Honghua Zhao, Cong Liu, Jin Zhang, Louis Ge
Summary: Through SHPB tests, the breakage behavior of Nishan rock and Shoushan rock particles under different strain rates was investigated. It was found that their dynamic peak strengths increase with strain rate, and a dynamic increasing factor was used to describe this strain rate effect. Analysis of grain size distribution of fractured rock particles and the use of fractal theory revealed differences in dynamic strength variation with fractal dimension for the two types of rock particles.
COMPUTATIONAL PARTICLE MECHANICS
(2021)
Article
Materials Science, Multidisciplinary
Tao Zhang, Lan Yan, Lianjie Li, Mingshuai Huo, Hui Wu, Xuming Zha, Ningchang Wang, Xian Wu, Feng Jiang, Zhengyi Jiang, Xipeng Xu
Summary: Grain refinement has a significant impact on mechanical properties, and establishing the relationship between grain evolution and plastic behavior is essential. Through experimental research, it was found that the grain size has a significant influence on the yield stress, strain rate sensitivity, and thermal softening. Based on these findings, a new constitutive model was developed to accurately predict the mechanical behavior of the material.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Engineering, Geological
Cheng Pan, Xing Li, Lei He, Jianchun Li
Summary: A method coupling the discrete element method with the cohesive zone model was proposed to study the influence of mineral grain size distribution and preferred orientation on the mechanical behavior and failure mode of rocks. Numerical examinations showed a relationship between micro-geometric heterogeneity and the mechanical properties and failure mode of rocks.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Ziyu Wang, Kaoshi Zhang, Yanqiao Song, Raneen Abd Ali, Wenliang Chen, Xingxing Wang
Summary: This study investigated the mechanical behavior and microstructure evolution of 2060 Al-Li alloy under high strain rates. The results showed that high strain rates led to increased dislocation density and grain refinement in the alloy, as well as affected the structure of grain boundaries.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Environmental
Liwang Liu, Haibo Li, Xiaofeng Li, Renjie Wu
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2020)
Article
Engineering, Geological
Renjie Wu, Haibo Li, Xiaofeng Li, Xiang Xia, Liwang Liu
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2020)
Article
Engineering, Geological
G. K. Zhang, H. B. Li, M. Y. Wang, X. F. Li
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2020)
Article
Engineering, Multidisciplinary
X. F. Li, H. B. Li, J. Zhao
Summary: This study aims to understand the effects of micro-heterogeneity on the initiation, propagation, and coalescence of microcracks in rocks. The research reveals that grain size, morphology, and mineralogy play significant roles in determining the mechanical properties of rocks, such as crack initiation stress and compression strength.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Engineering, Geological
Minghe Ju, Xiaofeng Li, Jianchun Li
Summary: The experimental study reveals that the transition of rock fracture from local splitting to pervasive pulverisation is strain-controlled, leading to asymmetric damage in fault zones. As strain increases, different fracture patterns develop, ultimately broadening the scale of pulverisation due to cumulative damage. The linear correlation between energy absorption and strain allows for a good prediction of experimental data on the relationship between strain and loading cycles.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Engineering, Geological
Liwang Liu, Haibo Li, Xiaofeng Li, Di Wu, Guokai Zhang
Summary: This study proposed a novel method to quantitatively determine the crack initiation mechanism in granitic samples using digital image correlation (DIC) analysis. The research found that with the increase of inclination angles, the crack initiation mechanisms changed, with wing cracks transitioning from mixed mode I/II cracks to mode I cracks, and anti-wing cracks remaining dominated by mode II cracks.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Construction & Building Technology
Guokai Zhang, Mingyang Wang, Xiaofeng Li, Songlin Yue, Zhu Wen, Songtong Han
Summary: The presence of preexisting defects has a significant impact on the fracture behaviors in rock engineering, with the angle of the flaw affecting the initiation stress of micro- and macrocracks. The study suggests using AE monitoring to identify crack initiation stages rather than relying solely on stress-strain behaviors, photographic observations, or P-wave measurements.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Computer Science, Interdisciplinary Applications
Ben Wang, Haibo Li, Zhushan Shao, Shihai Chen, Xiaofeng Li
Summary: This study presented a hybrid continuum-discontinuum method to investigate the rock-breaking mechanism resulting from high-pressure gas blasting, and found significant differences in crack patterns, fracture mode, and vibration attenuation between high-pressure gas blasting and explosive blasting.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Engineering, Geological
Haozhe Xing, Mingyang Wang, Minghe Ju, Jianchun Li, Xiaofeng Li
Summary: The study utilized the high-speed three-dimensional digital image correlation (3D-DIC) technique to investigate the ejection velocity characteristics of rock fragments in dynamic compression tests. It was found that the fragment movement is successively accelerated by various factors, and the ejection velocity varies with size and strain rate.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Review
Mechanics
Minghe Ju, Xiaofeng Li, Xing Li, Guanglei Zhang
Summary: This article reviews the effect of weak interfaces on crack propagation in rock and similar brittle materials, discussing the phenomenon, mechanism, and classification of influence factors, mechanical behaviors, and action mechanisms.
ENGINEERING FRACTURE MECHANICS
(2022)
Review
Engineering, Geological
Liwang Liu, Haibo Li, Xiaofeng Li
Summary: The mechanical properties and failure behavior of rocks with flaws or discontinuities have been extensively studied in the field of rock mechanics. This paper provides a systematic review of experimental results on pre-cracked rocks under quasi-static compression. The influence of flaw geometries, filling conditions, and confining pressure on the mechanical characteristics of rocks is discussed. The cracking process is evaluated in terms of crack initiation, coalescence, and failure patterns.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2022)
Article
Energy & Fuels
Xing Li, Cheng Pan, Xiaofeng Li, Chengmeng Shao, Haibo Li
Summary: This research used a synthetic rock mass approach to study crack propagation and coalescence during underground blasting. It was found that pre-existing fractures have a restraining effect on blasting-induced crack propagation, but this effect weakens as fracture length or density increases. In addition, the mismatch between borehole centerline and high in situ stress direction also affects crack coalescence.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2022)
Article
Engineering, Multidisciplinary
Ben Wang, Haibo Li, Haozhe Xing, Xiaofeng Li
Summary: Gas pressurization plays a significant role in driving fractures and enhancing fragmentation in CO2 blasting. It increases the fracture zone and crack count, reduces the average size of fragments, and increases the fractal dimension of the debris distribution. Gas pressurization also leads to more serious vibration disasters.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2022)
Article
Engineering, Geological
L. Liu, H. Li, X. Li, C. Zhou, G. Zhang
Summary: In this study, the effect of mineral microstructure on crack growth and mechanical properties of heterogeneous rocks with a single pre-existing flaw under uniaxial compression was investigated using the discrete-element method combined with a grain-based model. The results show that characteristic stresses increase with the inclination angle, and intergranular cracks initiate prior to intragranular cracks. Ultimately, the numerical simulations of failure patterns align well with experimental results, revealing a combination of intragranular and intergranular cracks at the grain scale.
GEOTECHNIQUE LETTERS
(2021)
Article
Engineering, Mechanical
A. P. Simonov, I. V. Sergeichev
Summary: The direct impact method provides a higher sample deformation rate and reliable results for materials with low yield strength and hardening rate. This study proposes an alternative procedure for calculating the strain rate in order to improve accuracy of the direct impact method for a wide range of metals and alloys. The proposed method has been validated through finite element analysis and direct impact tests, and it qualitatively changes the shape of the stress-strain curve by adding an unloading area.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Qiang Wei, Zifeng Li
Summary: This study investigates the dynamic bifurcation of a column when it impacts a rigid plane vertically, which is different from the classical Eulerian static buckling. The findings show that either the dimensionless critical buckling time or the dimensionless critical buckling velocity can be used to determine whether buckling has occurred. Different dimensionless initial defects in the column result in different dimensionless displacement responses, and the nonlinear effect influences the analysis results.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
M. C. Price, M. J. Cole, K. H. Harriss, L. S. Alesbrook, M. J. Burchell, P. J. Wozniakiewicz
Summary: This article introduces a new gas gun developed at the Centre for Astrophysics and Planetary Science, University of Kent, which can produce vertical impacts at speeds up to 2 km/s. The gun design, assembly, operation, and ancillary components are described in detail. The experimental results demonstrate that the gun performs as expected.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Fanny Gant, Gabriel Seisson, Patrice Longere, Skander El Mai, Jean-Luc Zinszner
Summary: The article investigates the high strain rate response of metals and alloys under radial expansion and compares different materials. The results show that different materials exhibit different responses in terms of deformation and fracture.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
M. D. Fitzgerald, J. D. Pecover, N. Petrinic, D. E. Eakins
Summary: This study investigates the mechanism for the destruction of thick flyers accelerated using electric guns and proposes strategies for mitigating their break-up based on experimental results and mathematical models. The findings suggest that limiting the maximum pressure within the flyer and extending the current rise time can prevent flyer failure, increasing the efficiency and shock duration of the electric gun.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Guowen Gao, Enling Tang, Guolai Yang, Yafei Han, Mengzhou Chang, Kai Guo, Liping He
Summary: In this study, the dynamic constitutive model of Al/Ep/W material was investigated and verified through experiments and numerical simulations. The proposed model accurately described the mechanical behavior of the material under high strain rates, providing an important reference for evaluating the response characteristics of the new energetic material projectile to lightweight aluminum armor.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Minzu Liang, Meng Zhou, Xiangyu Li, Yuliang Lin, Fangyun Lu
Summary: UHMWPE fiber mesh reinforced polyurea composites improve structural strength and blast resistance performance, and can alter the failure mode. Loose filler is generated as polyurea melts and fragments penetrate. Joint loads are classified into three categories based on their connection and duration.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Ashutosh Jha, Guglielmo Cimolai, Iman Dayyani
Summary: The present article introduces the Zero Poisson's Ratio Fish Cells metamaterial and investigates the effects of Poisson's ratio on the crashworthiness of different lattice structures. Numerical results demonstrate that the Zero Poisson's Ratio model possesses greater stability and structural integrity with minimal edge deformations.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Hongbo Zhang, Dayong Hu, Xubin Ye, Xin Chen, Yuhuai He
Summary: This study investigated the impact of spherical foreign objects on simulated blade edges through experimental and theoretical analysis. The experimental results showed that increasing impact energy resulted in larger damage sizes, and three distinct types of deformations were observed in FOD. Accurate FOD prediction models were developed using linear and power formulas. The theoretical analysis using a spring-mass system based on Winkler's elastic-plastic foundation theory yielded results in good agreement with experimental measurements, providing a reference for fatigue life assessment of aeroengine blades.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
L. M. Reitter, Y. A. Malik, A. B. Jahn, I. V. Roisman, J. Hussong
Summary: This study characterizes the dynamic strength of wet granular ice layers through impact tests. The results reveal strong connections between ice particles in ice layers generated by ice crystal accretion. Comparable strength values can be obtained by reinforcing ice particle connections in ice layers prepared in the laboratory.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Kyle Mao, Genevieve Toussaint, Alexandra Komrakova, James D. Hogan
Summary: In this study, the Generalized Incremental Stress State dependent damage MOdel (GISSMO) is used to simulate the high-velocity impact failure of Armox 500T steel. The GISSMO is calibrated and validated using experimental data from the literature, and is then applied to investigate the impact failure behaviors of bi-layered steel systems. The results provide new capabilities and insights for the design of armor structures and evaluation of impact failure behaviors in Armox 500T/RHA bi-layered systems.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Asim Onder
Summary: This paper investigates the performance of bumper plates with wavy surfaces under hypervelocity impact and finds that they are more effective in decreasing the impact energy compared to flat plates. The study also reveals the distinctive debris cloud generation that has never been reported before.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Zhi-Yong Yin, Xiao-wei Chen
Summary: This study numerically reveals three typical fracture modes of explosively-driven metal shells and investigates the influencing factors of different fracture modes through experimental data and dimensional analysis.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Jiri Pachman, David J. Chapman, Marek Foglar, Martin Kunzel, William G. Proud
Summary: Through the study of different types of concrete, it was found that despite their compositional complexity, range of compressive strengths, and reinforcement methods, the average Hugoniot data were remarkably similar between different concrete types.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)
Article
Engineering, Mechanical
Konstantin Kappe, Klaus Hoschke, Werner Riedel, Stefan Hiermaier
Summary: This paper presents a multi-objective optimization procedure for effectively designing gradient lattice structures under dynamic loading. The aim is to maximize energy absorption characteristics and achieve a lightweight design. Through considering design variables such as the relative density and density gradient, the peak crushing force reduction and maximized specific energy absorption are simultaneously optimized. A simplified beam-based finite element model is used to efficiently model and simulate the lattice structures. An artificial neural network is trained to predict energy absorbing characteristics and find optimal lattice structure configurations. The network is trained using a multi response adaptive sampling algorithm, allowing parallel simulation with automatically generated finite element models. A multi-objective genetic algorithm is then used to find optimal combinations of design parameters for lattice structures under different impact velocities and cell topologies.
INTERNATIONAL JOURNAL OF IMPACT ENGINEERING
(2024)