Article
Engineering, Multidisciplinary
Youjun Ning, Qi Lu, Xinlian Liu
Summary: In this study, the numerical manifold method (NMM) was improved to better simulate rock cracking. The simulations reproduced the crack development path accurately and matched the theoretical and experimental results. It was also found that the number and distance of pre-existing cracks have a significant influence on the strength of the rock.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Engineering, Multidisciplinary
Liang Yang, Yongtao Yang, Hong Zheng, Zhijun Wu
Summary: The paper proposes an algorithm in which the values of phase field are used to identify crack paths, and physical patches are then cut by reconstructed crack paths to obtain explicit cracks and jump displacement field. The numerical examples demonstrate the predictions of various explicit cracks by the proposed method are in good agreement with literature, and Sneddon's example verifies the discontinuous displacement field across explicit cracks is consistent with the closed form solution. The proposed numerical model warrants further investigation.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Jinjie Zhou, Fankai Xian, Jinchuan Shen
Summary: The crack propagation mechanism of Cu nanowires was investigated using molecular dynamics methods. The microstructural evolution of crack propagation was analyzed at different strain rates and crack depths. The competition between lattice recovery and dislocation multiplication was found to determine the crack propagation mode. Lattice recovery dominated the plastic deformation at low strain rates, resulting in shear fracture. With increasing strain rate, the plastic deformation mechanism shifted to dislocation multiplication, leading to ductile fracture. Interestingly, the crack propagation mechanism also varied with crack depth, with deeper cracks having weaker deformation resistance and a higher likelihood of crack propagation.
Article
Engineering, Mechanical
Chunjiang Zou, Jianchun Li, Xiaobao Zhao, Jian Zhao
Summary: Dynamic loading significantly affects the mechanical properties and cracking behaviors of rocks, with tensile strength being more sensitive to strain rate and tensile cracks being suppressed. The model proposed in this paper successfully explains the difference in fracturing behaviors under quasi-static and dynamic loadings. The well-correlation between experimental and modelling results indicates the potential of the model to quantitatively analyze complex macroscopic problems involving high strain rates.
EXTREME MECHANICS LETTERS
(2021)
Article
Mechanics
Wenshuai Han, Shuhong Wang, Wenfang Liu, Wenpan Sun, Qinkuan Hou, Simiao Zhang, Wei Wei
Summary: In this paper, a hybrid numerical manifold method with node-based strain smoothing and double-interpolation is proposed for crack analysis and propagation. The method achieves high accuracy and continuous nodal stress solutions in the entire domain, addressing the issue of empty strain smoothing domain and maintaining flexibility in domain formulation. The proposed model is validated through comparisons of analytical and experimental results, demonstrating accuracy and efficiency in crack analysis and growths.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Mechanics
Youjun Ning, Xinlian Liu, Ge Kang, Qi Lu
Summary: This research focuses on the use of the numerical manifold method (NMM) to simulate the crack initiation, propagation, and coalescence in brittle materials under dynamic loading. The results show that the NMM is able to accurately reproduce the crack behavior in these materials.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Ge Kang, Zheng Yang, Peng-wan Chen, Rui Liu, You-jun Ning, Si-ping Pang
Summary: Particulate-filled composite (PFC) is a complex multi-phase material, and it is difficult to reveal its deformation and damage mechanism using traditional macro-scale methods. The study used the numerical manifold method to simulate the meso-scale mechanical response of PFC, analyzed the damage morphology evolution of PFC, derived macroscopic equivalent damage evolution equations, and discussed the effects of loading levels on mechanical properties. Two categories of constitutive models were proposed to describe the macroscopic equivalent mechanical behavior of PFC.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Wang Shiqiang, Zhang Junhao, Yu Peihang, He Sha, Li Tao, Xu Qiang
Summary: This paper studied the fatigue damage of high-pressure manifold with connection threading by analyzing strain signals. The results showed significant strain difference when there is a crack at the root of the thread, and the strain concentration coefficients of different stress concentration points changed regularly. This study provides a theoretical and practical basis for the prediction of root cracks in connection threads.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Mechanics
Wen Li, Peiyan Huang, Zhanbiao Chen, Guowen Yao, Daiheng Chen
Summary: A single-side J-integral method is proposed to accurately evaluate the debonding failure behavior of the interface between two materials, such as a fiber reinforced polymer (FRP)-concrete interface. The method is validated through experimental tests and calculations, showing its effectiveness in predicting debonding failure and identifying concrete cracks within the J-integral paths. This research is important for understanding interface debonding failure and the propagation direction of concrete cracks.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Huo Fan, Duruo Huang, Gang Wang
Summary: The four-way enhanced numerical manifold method (NMM) improves the simulation of crack propagation in rock media and progressive failure of jointed rock slopes by enhancing local approximation, numerical integration accuracy, cracking criterion, and contact formulation. Examples demonstrate the performance and application prospect of the presented NMM in stability and failure analysis of jointed rock slopes.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Mechanics
Liang Yang, Yongtao Yang, Hong Zheng
Summary: In this study, a PFNMM method was proposed for crack growth in brittle materials, combining the advantages of PFM and NMM. The proposed numerical model is suitable for simulating multiple crack propagation problems and has been validated through benchmark examples. Further investigation on the convergence of numerical solutions from the PFNMM is recommended.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Chemistry, Multidisciplinary
Nan Yang, Yongshang Li, Ronggui Ma
Summary: This study addresses the problem of efficiently detecting cracks and sealed cracks in asphalt pavements through the use of deep learning. It creates a dataset, develops crack annotation methods, and conducts experiments to achieve efficient and accurate crack detection.
APPLIED SCIENCES-BASEL
(2022)
Article
Engineering, Electrical & Electronic
Hyeji Choi, Soyeong Kwon, Jungeun Song, Jaerang Lim, Bojung An, Soo Ho Choi, Ki Kang Kim, Hyeong-Ho Park, Dong-Wook Kim
Summary: Monolayer MoS2 devices with Au electrodes were fabricated on SiO2/Si substrates with 50 nm high SiO2 nanopillar (NP) array patterns. Cracks generated by NP-induced mechanical strain produced suspended MoS2 flakes, which exhibited distinct light-induced charging behaviors compared to nonsuspended flakes on flat SiO2. The strain-induced potential gradient in the MoS2 flakes on the NPs could cause exciton dissociation and charge migration under illumination, leading to light-induced charging with polarity and amount determined by strain states and initial net charges.
ACS APPLIED ELECTRONIC MATERIALS
(2021)
Article
Engineering, Geological
Ge Kang, Youjun Ning, Pengwan Chen, Siping Pang, Yongbo Shao
Summary: In this study, numerical manifold method was used to simulate the fracturing of rock specimens, showing good agreement with experimental and theoretical results in terms of crack initiation, propagation, interaction, and coalescence. The research findings provide a new method for solving rock fracturing problems and investigating the mechanical response of specimens with multiple cracks.
Article
Materials Science, Multidisciplinary
Chengbao Hu, Qingda Yang, Daosheng Ling, Fubin Tu, Liang Wang, Shilin Gong
Summary: This paper presents an integrated numerical algorithm based on the nonlinear augmented finite element method (N-AFEM) to accurately simulate the arbitrary evolving strong discontinuities and failure behaviors in geotechnical structures. By introducing novel nonlinear elemental augmentation and condensation scheme, a modified exponential cohesive zone model, and a nonlinear yielding function based on the Mohr-Coulomb strength theory, the method successfully describes the fracture process of geomaterials. Several benchmark examples were simulated to validate the proposed method by comparing predicted results with existing numerical or experimental data.
MECHANICS OF MATERIALS
(2021)
Article
Engineering, Geological
Yi Cheng, Louis Ngai Yuen Wong
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2020)
Article
Engineering, Geological
Zhihuan Li, Louis Ngai Yuen Wong, Cee Ing Teh
ROCK MECHANICS AND ROCK ENGINEERING
(2020)
Article
Computer Science, Interdisciplinary Applications
Zhijun Wu, Xunkai Ji, Quansheng Liu, Lifeng Fan
COMPUTERS AND GEOTECHNICS
(2020)
Article
Energy & Fuels
Qi Zhang, Xiao-Ping Zhang, Pei-Qi Ji, Han Zhang, Xuhai Tang, Zhijun Wu
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2020)
Article
Engineering, Geological
Louis Ngai Yuen Wong, Yahui Zhang, Zhijun Wu
ENGINEERING GEOLOGY
(2020)
Article
Engineering, Mechanical
Zhaofei Chu, Zhijun Wu, Quansheng Liu, Baoguo Liu
JOURNAL OF ENGINEERING MECHANICS
(2020)
Article
Engineering, Geological
Lifeng Fan, Meng Wang, Zhijun Wu
ROCK MECHANICS AND ROCK ENGINEERING
(2020)
Article
Engineering, Geological
Zhijun Wu, Mengyi Li, Lei Weng
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2020)
Article
Engineering, Geological
Lifeng Fan, Jingwei Gao, Xiuli Du, Zhijun Wu
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2020)
Article
Engineering, Geological
Jun Peng, Louis Ngai Yuen Wong, Yahui Zhang
Summary: The aggregation of a group of pore-like flaws significantly influences the strength, deformation properties, and microcracking process of crystalline rock. As the number of pores increases, the uniaxial compressive strength and elastic modulus of the rock decrease. Randomly distributed pores cause more uniformly distributed stress and smaller tension zone in numerical models compared to regularly assembled pores. The position of pore-like flaws has negligible influence on the strength and deformation behavior, while the UCS increases progressively with the radius of the pore-like flaw.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Engineering, Geological
L. F. Fan, L. J. Wang, M. Wang, Z. J. Wu
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2020)
Article
Engineering, Geological
L. F. Fan, M. Wang, Z. J. Wu
Summary: The study investigated the overall dynamic mechanical behavior of a double-scale discontinuous rock mass with a nonlinear deformational macrojoint, and concluded that the effects of nonlinear and linear deformational macrojoints on large amplitude stress wave propagation can be overlooked in certain frequency regions. The influence of microdefects on stress wave propagation increases with the frequency of the incident stress wave.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Engineering, Geological
Xin Cui, Louis Ngai Yuen Wong
Summary: Previous studies have shown that 3D wing cracks can extensively propagate under biaxial compression, while their propagation is somehow restricted under uniaxial compression. In this study, a numerical model is developed to simulate the propagation of 3D wing cracks, and it is found that intermediate principal stress plays a key role in triggering extensive propagation.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Geological
Yimeng Zhou, Louis Ngai Yuen Wong, Keith Ki Chun Tse
Summary: Rock classification is important for geosciences and geological engineering practices. This study develops and implements a convolutional neural network (CNN) called HKUDES_Net to classify seven different rock types. HKUDES_Net outperforms other CNNs and machine learning algorithms in terms of prediction accuracy.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Retraction
Engineering, Geological
Yimeng Zhou, Louis Ngai Yuen Wong, Keith Ki Chun Tse
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Construction & Building Technology
Qi Jiang, Wei Liu, Shaopeng Wu, Xuanwen Gou
Summary: This study analyzes the erosion mechanisms of NaCl solution on asphalt concrete and finds that NaCl solution softens asphalt and promotes the intrusion of crystalline salt into it. Salt crystallization alters the surface roughness of aggregates, resulting in a decrease in skid resistance but an improvement in compressive strength. Additionally, the concentration of NaCl solution initially has no significant impact on the mechanical performance of asphalt concrete, but its domination gradually increases with the intensification of cyclic effects.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Lili Kan, Lan-qing Dai, Ning Kong, Bin Peng, Fei Wang
Summary: This paper investigates the effect of freezing and thawing cycles on the tensile behavior of cracked ultra-high performance concrete (UHPC). The results show that long-term freezing and thawing action deteriorates the cracking strength, tensile strength, tensile strain, and strain energy of cracked UHPC. On the other hand, the action of water generally favors the development of tensile properties of UHPC. The crack distribution tends to be unsaturated under freezing and thawing environment, and the re-hydration reaction is hindered. The pore structure near the crack varies under different environments.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Xin Xiao, Jingwei Li, Qingke Meng, Xiangshan Hou, Yanhui Liu, Xujiang Wang, Wenlong Wang, Shengtao Lu, Yuzhong Li, Yanpeng Mao, Tong Li
Summary: Preparing gypsum-based self-leveling mortar (GSLM) using beta-hemihydrate gypsum and solid wastes-derived sulfoaluminate cement (WSAC) can improve the mechanical performance of the mortar, but phosphorus impurities can weaken the hydration speed and degree.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Sihang Bao, Junzhen Di, Yanrong Dong, Ziqing Gao, Qing Gu, Yuanfang Zhao, Hongyu Zhai
Summary: Tailings dam break and leakage accidents pose a threat to the safety of people in mining areas and cause severe environmental pollution. This study focuses on solidifying tailing sand using microbial induced calcite precipitation (MICP) to improve strength and fix heavy metals. The curing time of MICP bio-cemented tailings is found to significantly impact the strength of tailings, while its effect on heavy metal fixation is minimal. The optimized MICP curing time is 10 days, resulting in improved strength and cementation of tailings particles.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Ferhat Benmahiddine, Fares Bennai, Achraf Charaka, Ameur El Amine Hamami, Abdelkader Tahakourt, Rafik Belarbi
Summary: This paper studied the effects of hysteresis on the hygrothermal behavior at the building scale. Through laboratory validation and numerical simulations, it was found that hysteresis has a significant impact on the relative humidity and total heat fluxes in buildings, while it does not have a noticeable effect on temperature variations.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
You Gao, Wei He, Xiayang Zhang, De'an Sun, Pei Li
Summary: This study determined the boundary line between the swelling and compression deformation zone in lateritic clay through wetting tests, and proposed a simple bimodal SWRC model. It also found that the existing strength model underestimated the tested values in the medium to high suction range, therefore a segmented strength equation was introduced for enhanced predictions of the strength properties of lateritic clay.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Prabhath Ranjan Kumar Soda, Asheer Mogal, Kalyan Chakravarthy, Nikhil Thota, Nimish Bandaru, Sanjay Kumar Shukla, K. M. Mini
Summary: This study investigates the use of encapsulated bacteria to improve the self-healing ability of concrete. Through various tests, it is found that using 20% cement-coated alginate beads (CCAB) and 5% nanosilica (NS) can achieve optimal strength and healing. This research is significant for enhancing the durability of concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Shizhe Wang, Haiping Wu, Wen Yang, Wei Wang, Zhibo Zhu, Kun Nie, Luoxin Wang, Hua Wang, Jing Wu
Summary: In this study, photothermal-heat storage concrete (PHSC) was developed with excellent photothermal conversion performance and heat storage capacity. By absorbing and storing solar energy during the day and releasing it at night, PHSC can effectively reduce energy consumption in buildings.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Robin Deb, Jialuo He, Geetika Mishra, Yaghoob (Amir) Farnam
Summary: Incorporation techniques of phase change materials in cementitious composites have a significant influence on thermal properties. This study investigated the thermal behavior of low-temperature PCM when subjected to varying temperature change rates and pore confinement inside the porous network of lightweight aggregates. The results showed that ramp rates affect the nucleation and crystallization growth process during the phase transition, and the pore structure of the aggregates affects the supercooling phenomenon and confinement pressure of the PCM.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Eduardo Ferreira, Payam Sotoudeh, Dagmar Svecova
Summary: This study investigates the fatigue behavior of concrete under different stress reversal conditions. The results indicate that stress reversal generally causes more severe damage and reduces the cycles to failure compared to tensile fatigue. Additionally, adding some level of compression contributes to the energy required for failure under stress reversal fatigue. Specimens with higher concentration of fractured aggregates achieve longer fatigue lives.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Mag Raj Gehlot, Sandeep Shrivastava
Summary: This study evaluates the compatibility relationship between plaster bonds and the substrate under an accelerated aging environment, and finds that incorporating an appropriate amount of granite cutting waste can improve the strength parameters and adhesion of the cement mortar.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Min Zhang, Qirui Luo, Mingke Deng, Shixing Zhao
Summary: This study investigated the bond behavior between carbon FRCM composites with added short fibers and concrete substrates. The effects of different factors were considered and 36 specimens were tested and discussed. The experimental results were analyzed in terms of failure mode, load-slip curve, and characteristic parameters, and the contribution of weft yarns was taken into account in the developed bondslip model.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Dengkai Liu, Hongniao Chen, Ray Kai Leung Su
Summary: The susceptibility of building stones to fire and high temperature was investigated in this study by examining their physical and mechanical properties. The results show that both compressive and tensile properties of stones are affected by temperature changes. The tensile strength is particularly sensitive to temperature changes, requiring special attention to the components subjected to tensile stress in stone buildings. Principal component analysis was used to predict the mechanical properties of stones, providing a new method for calculating the residual mechanical properties after high temperature or fire.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Joso Maria Raposo, Eduardo Cavaco, Luis Costa Neves, Eduardo Julio
Summary: This paper investigates the correlation between the friction coefficient and the surface roughness of concrete-to-concrete interfaces. Experimental tests were performed on specimens with different surface treatments, and the surface roughness parameters were analyzed and correlated with the shear strength and friction coefficient. The results showed that certain roughness parameters had a strong positive correlation with the friction coefficient, while others had little or no correlation. A novel combined roughness parameter with optimized correlation was proposed.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Chiara Riccardi, Massimo Losa
Summary: The interest in using bio materials in asphalt pavements is growing due to economic reasons and environmental benefits. This study aimed to review the use of bio extenders as additives in binders, with a focus on replacements greater than 20% of fossil binder. The properties of bio-extended binders were found to vary substantially depending on the biomass source and production process.
CONSTRUCTION AND BUILDING MATERIALS
(2024)