Article
Engineering, Geological
Zhu Zhong, Da Huang, Yixiang Song, Duofeng Cen
Summary: This study investigates the three-dimensional cracking and coalescence of rock joints through uniaxial compression tests and CT image reconstructions. Different fracture behaviors are observed based on the types and angles of the joints, and the instability of the rock blocks is found to be related to the characteristics of the joints.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Engineering, Geological
Zhan Yu, Jianfu Shao, Yue Sun, Minh-ngoc Vu, Carlos Plua, Gilles Armand
Summary: This study is part of numerical simulations carried out on an in-situ heating test conducted by Andra at the Meuse/Haute-Marne URL to investigate the thermo-hydromechanical behavior of the Callovo-Oxfordian COx claystone. A numerical model is developed to analyze the damage and cracking process in saturated claystone subjected to thermo-hydromechanical coupling, taking into account material heterogeneity distribution. The model is compared with in-situ measurements and analyzed to understand the excavation damage zone and heating fractures.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Geological
Daping Tai, Shengwen Qi, Bowen Zheng, Chonglang Wang, Songfeng Guo, Guangming Luo
Summary: In this study, the effects of joint row number and inclination on the stress-strain characteristics and failure mode of rock were investigated using numerical models and laboratory direct shear tests. The results showed that joints significantly increased post-peak energy dissipation but had little effect on energy proportion before the peak.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2023)
Article
Engineering, Geological
Jin-Zhou Tang, Sheng-Qi Yang, Derek Elsworth, Yan Tao
Summary: The study compares physical experiments with a three-dimensional bonded-particle discrete element model, finding that confining stress significantly strengthens the jointed sandstone and failure is controlled by the threshold angle of about 40 degrees. The 3D numerical approach replicates the deformation history of jointed rock samples accurately, providing a viable model for emulating the mechanical behavior of jointed rocks with high fidelity.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Green & Sustainable Science & Technology
Xueqin Chen, Zhenhui Liu, Baocai Wan, Bo Yao, Qiao Dong
Summary: In this study, the microscopic cracking characteristics of steel slag aggregate porous asphalt concrete (SSA-PAC) were investigated through laboratory tests and numerical simulations. The results provide valuable insights for the application of steel slag as a building material.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Mechanics
Shasha Qiu, Qinglin Duan, Yulong Shao, Songtao Chen, Weian Yao
Summary: This paper presents a combination technique to address the computational cost and high crack resolution requirements in three-dimensional phase-field modeling of cracks. The technique utilizes a simple and robust one-pass staggered solution scheme to implement a hybrid phase-field model, and incorporates adaptive mesh refinement using the predictor-corrector algorithm to minimize the number of nodes. The results show a significant reduction in computational cost and efficient modeling of complex crack events.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Multidisciplinary Sciences
Xingye Chen, Wei Jian, Zhijian Wang, Jun Ai, Yu Kang, Pengcheng Sun, Zhouheng Wang, Yinji Ma, Heling Wang, Ying Chen, Xue Feng
Summary: In this study, an automated wrap-like transfer printing prototype is proposed for fabricating 3D curvy electronics. The prefabricated planar circuits are integrated onto the target surface with full coverage assisted by a gentle and uniform pressure field. The feasibility of this technique in the development of complex 3D curvy electronics is demonstrated.
Article
Engineering, Electrical & Electronic
Chullhee Cho, Pilgyu Kang, Amir Taqieddin, Yuhang Jing, Keong Yong, Jin Myung Kim, Md Farhadul Haque, Narayana R. Aluru, SungWoo Nam
Summary: Inserting atomically thin interlayers, such as graphene, between metal thin films and substrates can enhance the strain-resilient electrical properties of flexible electrodes, resulting in unique electrical characteristics where electrical resistance gradually increases with strain.
NATURE ELECTRONICS
(2021)
Article
Engineering, Multidisciplinary
Jian-Ying Wu, Yuli Huang, Hao Zhou, Vinh Phu Nguyen
Summary: Phase-field models offer a seamless approach to simulate various phenomena related to cracks in a unified theoretical framework, showing significant progress in solving 3D fracture problems. By using advanced numerical methods, complex fracture patterns with millions of elements and degrees of freedom can be efficiently handled within acceptable computational time, enabling qualitative and quantitative comparisons with experimental results.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Shun Yu, Fangchan He, Junran Zhang
Summary: In this study, radial splitting tests were performed on Nanyang expansive soil using particle image velocimetry (PIV) test system. It was found that both undisturbed and remolded expansive soil specimens exhibited a strain-softening phenomenon during the drying process. The peak load increased with decreasing water content, and the remolded specimens had more regular fracture characteristics. These findings provide a scientific basis for the design and construction of geotechnical engineering related to expansive soil.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Geological
Wei Zeng, Yong-Fu Ye, Ze-Min Kuang, Wen-Ling Tian
Summary: In this study, a three-dimensional joint model is constructed using computed tomography scanning and digital image processing techniques. The model is integrated into a particle flow code to simulate triaxial compression tests under varying confining pressures. The results demonstrate the significant influence of rock fractures on the mechanical properties of rock masses, with the linear phase of the stress-strain curve being more pronounced at higher confining pressures.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Multidisciplinary Sciences
Hui Cheng, Hongbao Zhao
Summary: This paper numerically investigated the effects of loading area and joint angle on the strength dividing points, energy evolution, and crack distribution characteristics of non-persistent jointed rocks. The results showed that the closer the absolute value of joint angle to 45 degrees and the smaller the loading area, the lower the strength dividing points of rocks. Compared with joint angle, loading area had more influence on rock energy input, with larger loading areas resulting in higher crack characteristics.
Article
Chemistry, Multidisciplinary
Kai Huang, Zhanjun Li, Yang Li, Nuo Yu, Xiuping Gao, Ling Huang, Shuang Fang Lim, Gang Han
Summary: This study introduces a simple thermolysis-mediated colloidal synthesis method for CaF2:DygNaYF(4) core-shell PLNPs, which enhances persistent luminescence. The well-matched crystal lattices between CaF2 and NaYF4 allow for precise control of compositions, shapes, and enhanced luminescence, overcoming current synthesis challenges for heterostructured PLNPs.
Article
Geochemistry & Geophysics
Hamid Mehrabi
Summary: A new approach for deformation analysis using DInSAR method is proposed, selecting coherent cells with acceptable minimum coherence and estimating components of strain and differential rotation tensors using the recursive moving least squares method. The method successfully determines local and regional strain patterns in volcano areas.
JOURNAL OF GEODESY
(2021)
Article
Orthopedics
Christoph Zindel, Philipp Furnstahl, Armando Hoch, Tobias Gotschi, Andreas Schweizer, Ladislav Nagy, Simon Roner
Summary: The study found that experience in 3D operation planning and clinical experience are crucial for accurate reduction of distal radius fractures. Biomedical engineers and senior orthopedic residents demonstrated more accurate planning compared to junior orthopedic residents with less clinical experience and no 3D planning experience.
JOURNAL OF ORTHOPAEDIC SURGERY AND RESEARCH
(2021)
Article
Construction & Building Technology
M. H. Samarakoon, P. G. Ranjith, W. A. M. Wanniarachchi
Summary: This study examines the effects of carbonation on the properties and mechanisms of cement, showing that alkali-activated cements with higher calcium content exhibit better mechanical properties and a denser microstructure when exposed to carbonate brine.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Thermodynamics
Jizhao Xu, Cheng Zhai, Pathegama Gamage Ranjith, Shuxun Sang, Yong Sun, Yuzhou Cong, Wei Tang, Yangfeng Zheng
Summary: The study investigated the effects of liquid CO2 on coal strength, finding that the coupled effects of liquid CO2 temperature and adsorption can influence coal fracture behavior and crack morphology.
Article
Energy & Fuels
Jizhao Xu, Cheng Zhai, P. G. Ranjith, Shuxun Sang, Xu Yu, Yong Sun, Yuzhou Cong, Yangfeng Zheng, Wei Tang
Summary: The study found that coal affected by liquid CO2 exhibited more complex destruction patterns, larger fractal dimensions, and greater structure degradation. The affected coals showed diverse mechanical responses, with temperature shock and CO2 adsorption potentially leading to crack growth and strength deterioration, ultimately destroying the coal with smaller yield strength.
Article
Energy & Fuels
David Lall, Vikram Vishal, M. V. Lall, P. G. Ranjith
Summary: The study found that gas production was less efficient in the presence of a permeable heterogeneity compared to other scenarios. The permeability affects the vertical extent of dissolved methane volume during thermal stimulation and huff and puff, while well depth influences the radial extent of dissociated molecules.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Geological
Chunlin Zhong, Zhenyu Zhang, P. G. Ranjith, Chengpeng Zhang, Kangsheng Xue
Summary: The study found that pore water can affect the radial and volumetric strain evolution of coal, leading to dilation deformation. Additionally, due to the water propping effect, the cracks in saturated coal cannot close tightly during loading, causing sliding and generating numerous tensile cracks. Loading frequency can impact the decay of pore pressure, consequently influencing the number of cracks in coal.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Energy & Fuels
Shashika Gajanayake, Ranjith Pathegama Gamage, Pabasara Wanniarachchige, Decheng Zhang
Summary: This study conducted molecular dynamic simulations to investigate the effects of temperature, pressure, and initial CO2 concentration on gas replacement characteristics for methane recovery and CO2 storage. The results showed that higher temperatures resulted in greater methane recovery, but diminished CO2 storage capacity. Higher initial CO2 concentrations facilitated better CO2 penetration into the hydrate structure, leading to increased methane recovery and improved CO2 storage.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Geological
Miao Chen, Yuliang Zhang, Chuanwei Zang, Guangchao Zhang, Qi Li, Bingzheng Jiang
Summary: Rockburst is a challenging issue in the mining industry globally, and reaming borehole pressure relief technology has advantages in preventing and controlling rockbursts. The study investigates the impact of different borehole parameters on specimen's mechanical properties, crack evolution, and energy change laws through confined compression experiments. The results indicate that larger borehole diameter, longer reaming length, and smaller borehole spacing result in lower peak strength and elastic modulus.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Guanglei Zhou, Jiangwei Liu, Tao Xu, Heinz Konietzky, Chuanwei Zang, Guangchao Zhang, Miao Chen
Summary: An implicit gradient-enhanced nonlocal meso-scale damage model is developed to study deformation and fracturing in brittle materials. The model uses an implicit gradient integration scheme to address mesh dependency and strain localization. Mechanical parameters are randomly assigned using a Weibull statistical distribution to capture material heterogeneity at the meso-scale. The model employs a linear elastic damage constitutive law with residual strength to describe the stress-strain relationship and uses the Mohr-Coulomb criterion and tensile stress criterion to evaluate damage. The model is validated through benchmark tests and shows potential for simulating crack initiation and propagation processes in brittle materials while reducing mesh dependency.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Engineering, Mechanical
Miao Chen, Liu Yang, Chuanwei Zang, Yang Chen, Zhifeng Qi, Biao Kong
Summary: In this paper, the effects of distinct joint inclinations under pre-cyclic loading on the strength and failure characteristics of rock-like specimens were investigated through experiments and numerical simulations. The results show that cyclic loading decreases the strength of the specimen, and the strength characteristics are more apparent as the joint inclination angle becomes smaller. Insights into different upper limit stress fatigue behaviors were gained, and the damage degree of cyclic loading at high-stress levels is linked to the joint inclination angle and carrying capacity of specimens.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Geosciences, Multidisciplinary
Junpeng Ma, Guangchao Zhang, Guanglei Zhou, Yong Zhang, Xiangjun Meng, Yongqiang Zhao, Miao Chen
Summary: A numerical hydro-mechanical damage model is proposed to study the stability and failure characteristics of artificial dam in coal mine underground water reservoir. The model accurately replicates stress-strain curves and failure patterns, validated with experimental data for rock samples. The study explores the influence of water pressures, cutting depth, and dam strengths, and highlights the importance of dam strength in determining the strength of artificial dam. This modeling approach can assist in the management and optimization of underground water reservoirs.
GEOMATICS NATURAL HAZARDS & RISK
(2023)
Article
Green & Sustainable Science & Technology
Chuanwei Zang, Jia Zhou, Miao Chen, Feng Bai, Zhengyang Zhao
Summary: This paper focuses on the influence mechanisms of various factors on mining at a close distance under a residual coal pillar in a gently dipping coal seam group. The study uses the discrete element method (DEM) and orthogonal experiments to comprehensively consider multiple factors. The research reveals the joint instability mechanism of the lower coal seam, interlayer rock, coal pillars, and overlying strata under the disturbed conditions of lower panel mining.
Article
Geochemistry & Geophysics
Chuanwei Zang, Liu Yang, Miao Chen, Yang Chen
Summary: In this study, the reinforcement effect of grouting on the bearing capacity of broken coal in deep roadways was investigated by making grouting-reinforced specimens with different particle sizes. The appropriate water-cement ratio (W/C) of 0.45 was determined for field grouting conditions. Uniaxial compression tests were conducted on the grouting-reinforced specimens with 0.45 W/C using acoustic emission equipment for detection. Differences in failure modes, stress-strain curves, and acoustic emission signal characteristics were studied for intact coal samples, grouting-reinforced bodies with different particle sizes, and grouting-reinforced bodies after anchoring to reveal the deformation and failure patterns and elucidate the failure mechanisms of grouting-reinforced bodies with different particle sizes.
Article
Engineering, Geological
V. R. S. De Silva, H. Konietzky, H. Mearten, P. G. Ranjith, W. G. P. Kumari
Summary: This study proposes a novel approach called the hybrid rock pre-conditioning method to enhance the sustainability and efficiency of low-grade ore mining. The method involves the use of soundless cracking demolition agents (SCDAs) to initiate radial fractures in a predrilled host rock, followed by hydraulic stimulation to extend the fractures. The results show that this method can create a high density of fractures around the injection well, and key factors such as rock mass heterogeneity and stress anisotropy affect its performance.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Mechanical
Miao Chen, Yuliang Zhang, Guangchao Zhang, Guanglei Zhou, Zihui Wang
Summary: An improved reaming hole pressure relief technology is proposed to overcome the disadvantages of traditional large-diameter hole pressure relief technology. Through a series of compression tests and numerical simulations, the pressure relief mechanism and the evolution of cracks are analyzed. The research results provide a foundation for evaluating the pressure relief effect through stress and fracture monitoring methods on the surrounding rock mass.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Energy & Fuels
M. H. Samarakoon, P. G. Ranjith
Summary: Ensuring the intactness of cement sheaths is crucial for deep well applications in extreme underground conditions. This study investigates the behavior of wellbore materials, including steel casing, annulus cement sheaths, and surrounding rock formations, under continuous steam injection. The results show that materials in carbonate formations are more vulnerable to stress than those in sandstone formations, and the retention time of maximum temperature in cement sheaths is shorter in sandstone than in carbonate. It is also found that the cement sheaths in compliant formations like sandstone may fail due to tensile cracking along the thinnest thickness.
GEOENERGY SCIENCE AND ENGINEERING
(2023)
Article
Engineering, Mechanical
Zhuang Sun, Yixin Zhao, Yirui Gao, Sen Gao, Davide Elmo, Xindong Wei
Summary: In this study, the modified semi-circular bending test was used to investigate the fracture toughness of coal samples with different sizes and bedding angles. The results showed that the fracture toughness of coal exhibits size effect and anisotropy. The crack initiation and propagation in hydraulic fracturing of coal seam can be influenced by bedding angles.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Ruiming Zhang, Kai Ma, Wenzhu Peng, Jinyang Zheng
Summary: The fatigue crack growth rates of 4130X steel in different hydrogen concentrations were measured, and the influence of hydrogen on crack behavior was analyzed. Results show that the crack growth rate increases with increasing hydrogen pressure, reaching a threshold at 87.5 MPa.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Hien Do, Phuc L. H. Ho, Canh V. Le, H. Nguyen-Xuan
Summary: In this study, a new method for determining the limit loads of fracture structures using the pseudo-lower bound method with adaptive quadtree meshes is proposed. The method overcomes the volumetric locking problem and handles the challenge of hanging nodes during refinement procedure by using quadtree meshes. The effectiveness of the approach is demonstrated through numerical validation.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Weimin Song, Yuxin Fan, Hao Wu, Liang Zhou
Summary: This study proposed a novel test method to characterize the I-II mixed fracture toughness of asphalt pavement and investigated the effects of reclaimed asphalt pavement (RAP) and loading rate. The results showed that loading rate and inclusion of RAP had positive effects on fracture toughness.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Zida Liu, Diyuan Li, Jianqiang Xia, Quanqi Zhu
Summary: In this study, the influence of flaw inclinations on the failure mechanism of fissured granite specimens was analyzed through a series of experiments. A quantitative method combining deep learning and scanning electron microscope was employed to identify the mesoscopic fracture mechanism of macroscopic cracks. The results indicated that the failure of fissured specimens was mainly caused by tensile stress and shear stress.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Jiabing Zhang, Yiling Chen, Ronghuan Du, Xianglian Zhao, Jun Wu
Summary: This study investigated the mechanical characteristics and crack propagation behavior of sandstone-like samples with single cracks under freeze-thaw cycles. The results demonstrated the significant effects of crack angle and freeze-thaw cycles on the compressive strength and stability of the samples. Confining pressure inhibited the freeze-thaw deterioration, and the acoustic emission signals exhibited good consistency with the stress-strain curves. The simulation results matched well with the experimental results, and five crack propagation modes were proposed.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Felix Boedeker, Pauline Herr, Anders Biel, Ramin Moshfegh, Stephan Marzi
Summary: Cohesive Zone Models with finite thickness are widely used for fracture mechanical modeling. Computational homogenization techniques are crucial for the development of advanced engineering materials. FFT-based homogenization scheme shows potential in reducing computational effort and has practical applications.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Sobhan Pattajoshi, Sonalisa Ray, Yugal Kishor Joshi
Summary: In this work, a novel multi-layer composite structure is proposed for protective shelter design. The dynamic behavior and mechanical performance of the multi-layer composite under projectile impact loading are investigated. The proposed composite target demonstrates enhanced penetration resistance and lesser damage compared to its reinforced concrete monolayer counterpart. An analytical model is also developed to predict the forces transmitted to the lowest layer for design purposes.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
H. M. Shodja, M. T. Kamali, B. Shokrolahi-Zadeh
Summary: This study proposes a semi-analytical method for calculating the stress intensity factor of an internally pressurized eccentric annular crack. By using hypersingular integral equations and conformal mapping, accurate values of SIFs along the crack edges can be obtained. The material properties of the elastic matrix do not affect the SIF values, as demonstrated through the investigation of geometric parameters.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Wen Hua, Zhanyuan Zhu, Wenyu Zhang, Jianxiong Li, Jiuzhou Huang, Shiming Dong
Summary: Accurate assessment and prediction of fracture behavior in cracked materials using mixed mode fracture criteria are crucial in fracture mechanics. This study comprehensively reviewed modified fracture criteria that incorporate T-stress for mixed mode I-II cracks. A comparative analysis was conducted between experimental results and theoretical predictions for five different cracked configurations. The study also discussed the effect of T-stress on crack initiation angle and fracture toughness, providing suggestions. The results showed variations in predictive accuracy across different cracked configurations due to disparities in T-stress. However, similar predictions were observed for semi-circular bend and edge-crack triangular specimens due to their similar biaxial stress ratio B. Different fracture criteria were suitable for different cracked configurations with positive or negative T-stresses.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Qing-qing Shen, Qiu-hua Rao, Wei Yi, Dian-yi Huang
Summary: This study proposes a theoretical approach to forecast multi-crack propagation trajectories in a finite plate. By calculating the stress intensity factor (SIF) and analyzing the influence of crack size, the criteria for crack initiation and propagation in a finite plate are established. Experimental results demonstrate that the SIF of multiple cracks in a finite plate is consistently larger than that of an infinite plate.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Songbai Li, Qiyun Zhu, Zhizhong Lu, Hongzhi Yan, Chu Zhu, Peize Li
Summary: This study investigates the effects of laser heating and laser shot peening on fatigue life of AA2524, and predicts the fatigue life using artificial neural networks and support vector regression models. The results show that laser heating and laser shot peening can significantly improve the fatigue life, and the neural networks have better prediction ability.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
V. Shlyannikov, A. Sulamanidze, D. Kosov
Summary: This paper presents experimental crack-growth data for thermomechanical fatigue conditions in nickel-based alloy components. The crack-growth experimental results are interpreted using finite element analyses and multi-physics numerical calculations. The results show that crack growth rate is slower under isothermal pure fatigue conditions, while it is faster under thermomechanical cyclic deformation conditions.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Tairui Zhang, Xin Ma, Bin Yang, Wenchun Jiang, Zhiqiang Ge, Xiaochao Liu
Summary: This study experimentally investigated the fracture toughness distributions in dissimilar metal welds. The predictions of fracture toughness were made using three criteria and an energy release rate model. The results showed that using the critical strain criterion and ERR model resulted in higher consistency compared to mini-CTs, while the predictions using the critical stress criterion had high dispersion. The study also investigated the source of errors through damage developments and SEM observations.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)
Article
Engineering, Mechanical
Yike Dang, Zheng Yang, Xiaoyu Liu, Jianghao Guo
Summary: This study uses discrete element modeling to examine bedded rock failure with parallel defects. It is found that bedding influences crack propagation direction but has limited impact on final failure. Shear failure accumulates at the bridge area and defect tip, while tensile failure occurs during nucleation region development.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2024)