Article
Thermodynamics
H. W. Zhou, Z. L. Liu, J. C. Zhong, B. C. Chen, J. W. Zhao, D. J. Xue
Summary: A novel online observation approach that combines nuclear magnetic resonance imaging with triaxial loading techniques is employed to visualize and quantify the evolution of fracture and pore structure (FPS) in coal samples. The results indicate that increasing deviatoric stress leads to an increase in adsorption pore content and heterogeneity, as well as gas adsorption capacity of coal samples. However, the content and permeability of seepage pore and fracture initially decrease and then increase, while the heterogeneity of seepage space initially increases and then decreases.
Article
Mechanics
Sota Oshima, Tomoisa Mikami, Akinori Yoshimura, Yoshiyasu Hirano, Toshio Ogasawara
Summary: In situ observation was used to study the effects of mode mixity on microscopic damage and failure process in adhesively bonded carbon fiber reinforced plastic (CFRP) joints. The results showed that the damage and failure process were significantly influenced by the mixed-mode ratio of joints. An increasing mode I component led to the whitening of the adhesive resin due to cavitation, whereas an increasing mode II component resulted in an increased plastic zone length. The observed damage and failure process correlated with the stress state around the crack tip obtained by finite element analysis.
COMPOSITE STRUCTURES
(2023)
Article
Geochemistry & Geophysics
Shuang Dang, Jing Bi, Yu Zhao, Chaolin Wang, Kaizong Xia, Fei Gan
Summary: This study systematically revealed the deformation, energy evolution, and fracture characteristics of sandstone samples through multilevel and conventional unloading triaxial compression tests. The results showed that the initial confining pressure has a significant influence on the radial strain and energy growth factor of the sandstone. Multilevel unloading makes the energy conversion more adequate, reducing the possibility of rockburst.
Article
Engineering, Environmental
Xin Zhou, Xiaofei Liu, Xiaoran Wang, Hui Xie, Pengfei Du
Summary: This study investigates the damage mechanism of deep coal specimens under cyclic disturbance and different stress conditions. The results show that higher confining pressure allows the coal specimens to bear greater disturbance, with most fractures occurring during loading and unloading. Confining pressure weakens the electromagnetic radiation response of coal specimens in the compaction stage. The study also reveals a positive correlation between confining pressure and coal fragmentation, suggesting that higher confining pressure leads to smaller fractal dimensions of coal fragments. Energy analysis indicates that confining pressure and disturbance loading decrease post-peak fracture energy and residual strain energy, accumulating more elastic strain energy before fracture.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Chemistry, Multidisciplinary
Penghui Li, Yeqiang Bu, Linyan Wang, Chong Wang, Junquan Huang, Ke Tong, Yujun Chen, Julong He, Zhisheng Zhao, Bo Xu, Zhongyuan Liu, Guoying Gao, Anmin Nie, Hongtao Wang, Yongjun Tian
Summary: Fracture behaviors in perfect and twinned B4C crystals were studied via in situ TEM mechanical testing. It was found that cracks preferentially initiated at the twin boundaries (TBs) and propagated along them, resulting in the fracture of B4C. The theoretical calculations also showed a softening effect of TBs on B4C, with amorphous bands preferentially nucleated at the TBs. These findings clarify the atomic arrangement and the role of planar defects in the failure of B4C.
ADVANCED MATERIALS
(2022)
Article
Materials Science, Composites
Masao Kimura, Toshiki Watanabe, Sota Oshima, Yasuo Takeichi, Yasuhiro Niwa, Yuji Seryo, Masaki Hojo
Summary: This study investigates the nanoscale fracture mechanism in CFRPs using nanoscopic synchrotron radiation X-ray computed tomography. The results reveal the three steps involved in crack formation and the influence of fiber geometrical distributions on the resulting microstructures of cracks at the nanoscale.
COMPOSITES SCIENCE AND TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Yan-Shuang Yang, Meng-Yu Yin, Zhan-Rong Zhang, Si-Pei Cheng, Jia-Wen Hou
Summary: The triaxial compression performance of marble under different confining pressures and loading rates was studied using numerical tests. The results showed that the loading rate significantly affected the damage mode, strength parameters, and characteristic stresses of marble.
REVIEWS ON ADVANCED MATERIALS SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Xiang Wang, Sixue Zheng, Chuang Deng, Christopher R. Weinberger, Guofeng Wang, Scott X. Mao
Summary: By using in situ nanomechanical testing combined with atomistic simulations, the formation mechanisms of a 5-fold twin in nanostructured metals, such as gold, have been elucidated. Sequential twinning slip in varying slip systems and decomposition of high-energy grain boundaries play important roles in the formation process. The complex stress state in the neck area can also cause the breakdown of Schmid's law and result in 5-fold twin formation.
Article
Nanoscience & Nanotechnology
Haiyang Wang, Dylan J. Kline, Miles C. Rehwoldt, Michael R. Zachariah
Summary: This study demonstrates that adding carbon fibers into Al/CuO nanothermite sticks can significantly improve burn rate and heat flux, with the carbon fibers intercepting ejected hot agglomerates near the burning surface to enhance heat feedback. These approaches have the potential to enhance propagation and reduce two-phase flow losses.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Nanoscience & Nanotechnology
Yang Yan-Shuang, Li Kai-Yue, Zhou Hui, Tian Hao-Yuan, Cheng Wei, Zhang Zhan-Rong, Kaunda Musonda
Summary: CT scanning technology was used to investigate marble specimens under different confining pressures, revealing statistical regularity in the CT numbers with increasing confining pressure. The conventional triaxial tests showed higher average CT numbers compared to graded loading tests, while the variances were lower. Damage variables of the rock specimens decreased with increasing confining pressure, and were higher in graded loading tests compared to conventional triaxial tests.
REVIEWS ON ADVANCED MATERIALS SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
Yongyi Wang, Bin Gong, Chunan Tang
Summary: The study investigates the progressive failure process of columnar jointed basalts under different model boundaries and confining pressures using meso-damage mechanics, statistical strength theory, and continuum mechanics. Simulation results show variations in fracture processes and acoustic emission rules under different stress conditions, providing valuable insights into the fracture mechanism and energy evolution of CJBs.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Thomas Tancogne-Dejean, Christian C. Roth, Thilo F. Morgeneyer, Lukas Helfen, Dirk Mohr
Summary: This study investigates the fracture mechanism of aluminum alloy AA2024-T3 under shear loading using X-ray synchrotron laminography, revealing the microscale defects population and their evolution, and proposing a specific fracture mechanism based on these observations.
Article
Energy & Fuels
Zhibin Hao, Yujun Zuo, Hao Liu, Zehua Zhu, Jianyun Lin, Wenjibin Sun, Chao Pan, Lulin Zheng
Summary: This study reveals the damage evolution of jointed sandstone under different loading conditions using numerical models and experimental tests. A fractal dimension algorithm based on acoustic emission (AE) fields is proposed to assess the damage evolution. The findings are important for understanding the rules of jointed sandstone breakage and energy consumption, as well as searching for efficient and energy-saving rock-breaking technologies.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2022)
Article
Mechanics
Chuanju Liu, Qianjun Zhang, Qiang Zhu, Hongwei Deng
Summary: This study examines the dynamic fracture toughness of freeze-thawed granite. Freeze-thaw cycles are applied to treat granite samples, and the microstructure changes are measured using a nuclear magnetic resonance testing system. Dynamic testing with split Hopkinson pressure bar equipment is conducted to obtain the dynamic fracture toughness. Additionally, fractal geometry is used to analyze the roughness of the rock fracture surface and define FT damage. Based on these findings, a prediction model for dynamic fracture toughness is proposed, and the influence of F-T cycles and loading rate on fracture toughness is discussed.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Mathematics, Interdisciplinary Applications
Gaofeng Liu, Zhen Zhang, Yunxing Cao, Xiaoming Wang, Huan Liu, Baolin Li, Nian Si, Wenbo Guan
Summary: In this work, an analogical method for estimating the fractal dimension of three-dimensional fracture tortuosity (3D-FT) was proposed. A comparison and error analysis of analogical and rigorous methods on fractal dimension for 3D-FT were conducted. The proposed analogical method, which calculates the fractal dimension (DT-R) of 3D-FT as a function of average tortuosity (t(av)) and average fracture length (L-av), demonstrates high accuracy and good consistency with the rigorous method (DT-R).
FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY
(2023)
Article
Mechanics
Yang Liu, Shuangmei Zou, Ying He, Shuyu Sun, Yang Ju, Qingbang Meng, Jianchao Cai
Summary: In this study, an optimized color-gradient lattice Boltzmann model was applied to simulate steady-state two-phase flow in two-dimensional porous media with different rough surface conditions. It was found that surface roughness negatively affects both single-phase and two-phase fluid flow, with absolute and relative permeabilities decreasing with increasing roughness height or surface fractal dimension. This study provides valuable insights into the impact of surface roughness on two-phase flow behavior at a pore scale, which is essential for understanding macroscopic multiphase flow behaviors.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Geochemistry & Geophysics
Jiangtao Zheng, Wenhai Lei, Yang Ju, Moran Wang
Summary: The spontaneous imbibition behavior driven by capillary force in the pore space under actual reservoir conditions was studied using an improved multi-component pseudo-potential lattice Boltzmann method. The results showed that imbibition was two times faster and snap-off oil droplets phenomenon was observed under reservoir conditions. Investigating spontaneous imbibition in a real porous structure and under actual reservoir conditions is crucial for understanding the process and uncovering controlling mechanisms.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Energy & Fuels
Peng Liu, Yang Ju, Zheng Feng, Lingtao Mao
Summary: This study investigates the effects of natural fractures and horizontal geostress differences on the initiation of hydraulic fractures in coal seams using experimental research and numerical tools. The results show that the distribution of natural fractures plays a dominant role in the formation of the crack network.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2021)
Article
Energy & Fuels
Lei Zhang, Hongwei Zhou, Xiangyu Wang, Jiawei Zhao, Yang Ju, Tengfei Deng
Summary: Research on the permeability evolution of coal with the influence of temperature, matrix-fracture interaction, and creep deformation is of theoretical importance in gas control of deep coal mines. Experimental results show that the increase in matrix deformation during the creep process leads to a decrease in permeability. The developed permeability model considers the effect of temperature on matrix-fracture interaction and creep process, and can describe the experimental permeability evolution.
Article
Energy & Fuels
Lijun Wei, Mingqing Su, Kai Wang, Sining Chen, Yang Ju, Suijun Zhao, Xiangbei Kong, Yun Chu, Lixun Wang
Summary: The study found that ABC powder can effectively enhance the suppression effect of PE dust explosion by improving the thermal stability of PE particles and reducing the explosion chain reaction rate, but ethylene gas reverses the inhibitory effect of ABC powder, making the explosion of the mixture more difficult to control.
Article
Engineering, Multidisciplinary
Yang Ju, Chaodong Xi, Jiangtao Zheng, Wenbo Gong, Jianhao Wu, Shaojie Wang, Lingtao Mao
Summary: Accurate understanding and quantification of the 3D water-oil displacement process in porous reservoir rocks is crucial for enhancing petroleum recovery efficiency. This study utilized X-ray computed tomography and triaxial loading techniques to directly visualize and quantify the pore-scale physics and dynamic evolution of the displacement behavior. The results demonstrate the significant impact of stress-induced pore structure deformation on the displacement behavior and efficiency, providing valuable insights for improving petroleum recovery strategies.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2022)
Article
Engineering, Multidisciplinary
Lingtao Mao, Yu Lei, Leilei Ding, Jingcheng Wu, Liyun Li, Min Yang, Yang Ju, Fu-pen Chiang
Summary: This study investigates the 3D interior deformation of siltstone specimens using a series of uniaxial compression tests combined with in situ X-ray computed tomography. The specimens had pre-existing 3D surface flaws with different inclination angles and a flaw depth to specimen thickness ratio of 0.26. Digital volumetric speckle photography was used to quantify the 3D interior deformation and determine the distribution of displacement and major principal strain in different sections. The findings reveal the propagation mechanism of a single 3D surface flaw.
Article
Engineering, Environmental
Kai Wang, Long Wang, Yang Ju, Huzi Dong, Wei Zhao, Changang Du, Yangyang Guo, Zhen Lou, Han Gao
Summary: The study focused on the air leakage model considering three-dimensional stress and coal elastic-plastic deformation to prevent air leakage caused by mining-induced fractures around the borehole and roadway, which greatly affects the effect of underground gas drainage. Key parameters including initial permeability and sealing depth were analyzed to understand their influence on gas drainage effect.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Construction & Building Technology
Yang Ju, Changbing Wan, Guoming Fu, Lingtao Mao, Fu-pen Chiang
Summary: A new photoelastic testing method was developed to directly observe and quantify the full-field stress distribution and evolution in assembled lining structures. Experimental results verified the effectiveness of the proposed method in characterizing stress distributions within complex assembled lining structures.
TUNNELLING AND UNDERGROUND SPACE TECHNOLOGY
(2022)
Review
Energy & Fuels
Bin Pan, Teng Ni, Weiyao Zhu, Yongfei Yang, Yang Ju, Lijie Zhang, Shengnan Chen, Jianwei Gu, Yajun Li, Stefan Iglauer
Summary: This article provides a critical review of the key parameter of wettability in the methane-liquid-rock system, discussing its influence from experimental and theoretical perspectives, including pressure and temperature conditions, fluid properties, and rock surface characteristics. The article identifies current research gaps, provides future outlook, and draws several conclusions. The mini review contributes to the fundamental understanding of wettability in the methane-liquid-rock system under in situ reservoir conditions and offers useful guidance for shale gas/coalbed methane recovery and natural gas geo-storage.
Article
Chemistry, Physical
Bin Pan, Xia Yin, Weiyao Zhu, Yongfei Yang, Yang Ju, Yujie Yuan, Lijie Zhang, Stefan Iglauer
Summary: This study conducted a fundamental analysis of secondary imbibition in gas geo-storage operations. It found that the rate of secondary imbibition depends on factors such as gas type, formation depth, organic acid concentration, carbon number, and silica nanofluid. The findings provide valuable insights for understanding and optimizing gas geo-storage processes.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Mechanics
Yang Ju, Wenbo Gong, Jiangtao Zheng
Summary: Waterflooding technology is widely used to enhance oil recovery. However, the understanding of the influence of pore space topology on fluid displacement paths is limited. This study constructs digital pore models with various topologies and uses lattice Boltzmann method to predict the immiscible water-oil displacement. The results show that pore topology plays a key role in fluid displacement and is affected by fluid wettability.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2022)
Article
Engineering, Geological
Yang Ju, Yan Zhu, Yuwei Zhang, Hongwei Zhou, Suping Peng, Shirong Ge
Summary: This study investigates the effect of high-power microwave irradiation on the strength and microstructural changes of tar-rich coal. The results show a linear positive correlation between the overflow rate of coal gas and tar and microwave energy, while the uniaxial compressive strength and brittleness of tar-rich coal have a piecewise linear negative correlation with microwave energy. High-power microwave has a more significant effect on strength weakening, fracturing, and fragmentation of tar-rich coal. These findings provide insights for the in-situ conversion, high-efficiency utilization, and low carbon emissions of tar-rich coal using the technology of intelligent unmanned mining machine (IUMM).
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2022)
Article
Energy & Fuels
Shuo Zhai, Heping Xie, Peng Cui, Daqin Guan, Jian Wang, Siyuan Zhao, Bin Chen, Yufei Song, Zongping Shao, Meng Ni
Summary: The authors introduce a machine learning-driven approach to accelerate the discovery of efficient oxygen reduction electrodes for ceramic fuel cells by utilizing ionic Lewis acid strength as an effective physical descriptor. Experimental validation confirms the superior activity metrics of four oxides out of 6,871 distinct perovskite compositions, highlighting the importance of ISA in improving oxygen reduction reaction activity in perovskite oxides.
Article
Multidisciplinary Sciences
Heping Xie, Zhiyu Zhao, Tao Liu, Yifan Wu, Cheng Lan, Wenchuan Jiang, Liangyu Zhu, Yunpeng Wang, Dongsheng Yang, Zongping Shao
Summary: This article introduces a method for direct seawater electrolysis for hydrogen production, which can solve the problems of side reactions and corrosion. In the experiment, this method stably operated for over 3200 hours under practical application conditions. The method is efficient, size-flexible, scalable, and has high practical value without increasing the operation cost.