Article
Construction & Building Technology
Zhiheng Deng, Jiasheng Jiang, Haifeng Yang, Xiaoyan Wen, Junjie Mei, Qingmei Yang
Summary: To better understand the compressive behavior of coral aggregate concrete (CAC) with varying confinements induced by the lateral dilation of concrete, a series of experiments were conducted. The results showed that external confinement can increase the peak stress and peak strain of CAC, and an increase in axial and lateral strain was also observed. Samples confined with carbon fiber reinforced polymer (CFRP) exhibited elastic behavior in their lateral stress, while samples confined with aluminum alloy (AA) displayed elasto-plasticity behavior. The proposed damage-constitutive and bearing models showed good agreement with the measured results.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Mechanics
A. Moncy, O. Castro, J. Glud, C. Berggreen, O. T. Thomsen, J. M. Dulieu-Barton
Summary: A multi-scale stochastic crack density evolution model is proposed for tunnelling cracks under multi-directional cyclic loading. The model accurately predicts the crack growth and saturation level, as validated by experimental data and finite element analyses.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2023)
Article
Engineering, Mechanical
Rui Xiao, Thanh-Tam Mai, Kenji Urayama, Jian Ping Gong, Shaoxing Qu
Summary: Studies on the anisotropic damage behaviors of double network hydrogels under multi-axial deformation conditions have been conducted. Results indicate that the non-affine microsphere model accurately predicts directional damage of the primary cross-linked network and captures important features of experimental observations. This developed theoretical framework can enhance the fundamental understanding of anisotropic damage behaviors in various types of tough gels.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Engineering, Geological
Shuang Dang, Jing Bi, Yu Zhao, Chaolin Wang, Jiashen Li, Hao Hu
Summary: In this paper, multi-level triaxial cyclic loading and unloading (TCLU) compression tests were conducted on sandstone samples under varying upper limits of axial stress. The crack volumetric (deviatoric) strain curves and the characteristic stresses were obtained, and the evolution curves of the hysteresis loop, crack strain, and axial strain were analyzed. The strain evolution equation was applied to fitting analysis of axial and radial strain data, and good results were obtained. The damage evolution law, life prediction, and failure mechanism of the sandstone were revealed. The study helps to understand the failure mechanism of rock mass and evaluate the long-term stability of engineering rock mass.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Laura De Lorenzis, Corrado Maurini
Summary: This paper examines phase-field models under multiaxial stress states, uncovering fixed shapes of multiaxial strength surfaces and proposing a new energy decomposition for calibrating multiaxial failure surfaces.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Engineering, Ocean
Selase Kwame Mantey, Yi Zhang, Jianqun Jiang, Evans Amponsah, Zhenyu Wang
Summary: This study investigates the damage accumulation process of grouted connections of offshore wind turbines under variable axial fatigue load. Through cyclic compression tests and finite element numerical simulations, it is found that the grout damage under low load range can be accelerated by sudden large loads, and larger load range results in greater damage accumulation and reduced bearing capacity of the connection.
APPLIED OCEAN RESEARCH
(2022)
Article
Mechanics
Tobias Laux, Khong Wui Gan, Rodrigo P. Tavares, Carolina Furtado, Albertino Arteiro, Pedro P. Camanho, Ole T. Thomsen, Janice M. Dulieu-Barton
Summary: The study assesses a meso-scale damage modelling framework for composite laminates using experimental data obtained from a modified Arcan fixture. The model predicts multi-axial open-hole specimen strength with a mean relative error of 15%, showing good agreement with full-field measurements but revealing limitations in predicting shear-dominated damage modes.
COMPOSITE STRUCTURES
(2021)
Article
Engineering, Mechanical
C. A. Bronkhorst, H. Cho, P. W. Marcy, S. A. Vander Wiel, S. Gupta, D. Versino, V. Anghel, G. T. Gray
Summary: Accurately representing porosity-based ductile damage in polycrystalline metallic materials remains a significant challenge, but a soft-coupled linkage technique between a macro-scale damage model and micro-mechanical calculations has shown promise in this study. The micro mechanical model captures non-Schmid effects and suggests significant influences on local stress conditions across grain boundaries and triple junctions within the polycrystalline network.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Instruments & Instrumentation
Liqiang Ma, Hai Sun, Ichhuy Ngo, Jie Han
Summary: This paper presents a quantification approach to investigate the internal damage evolution of loading rock through surface infrared observation. By analyzing the changes in infrared radiation and acoustic counts, the damaged area of the rock can be accurately determined, and a quantitative method for characterizing the evolution of rock damage is established.
INFRARED PHYSICS & TECHNOLOGY
(2022)
Article
Mechanics
Y. Wang, Y. Z. Hu, S. H. Gao
Summary: This study investigated the fracture evolution characteristics of rocks under different interbed orientations using multi-level cyclic compressive loading experiments. The results showed that rock structure significantly impacted fatigue deformation, strength, and dynamic elastic modulus. A damage evolution model was established to simulate the accumulation of damage, revealing the influence of interbed orientation on crack propagation path and failure mode.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Chemistry, Physical
Danny Kojda, Tommy Hofmann, Natalia Gostkowska-Lekner, Klaus Habicht
Summary: This study synthesized nanostructured silicon and silicon-aluminum compounds using spark plasma sintering technology, and the interplay of metal-assisted crystallization and inherent porosity is used to suppress thermal conductivity. The research found that porosity and nanostructure have a significant impact on macroscopic heat transport.
Article
Construction & Building Technology
Bin Lei, Hongchen Yu, Yipu Guo, Wenkui Dong, Rui Liang, Xiaonan Wang, Xuqun Lin, Kejin Wang, Wengui Li
Summary: Multi-recycling of concrete waste is a promising solution for reutilization of construction and demolition wastes. This study investigates the combined effects of normal stress ratio (σ/fc) and number of recycling cycles (n) on the mechanical performance and damage evolution of Multi-RAC under compression-shear loading conditions. Both σ/fc and n significantly influence the failure mode, mechanical strength, stress-displacement relation, and damage evolution characteristics of Multi-RAC. The shear strength increases with increased σ/fc, but decreases with increased n. The proposed aggregate interlock model reveals the mechanism for the reduction of aggregate interlock strength with increasing n. The findings provide insights into the mechanical behaviors of Multi-RAC and can contribute to its application in structural concrete.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Chemical
Feng Guorui, Fang Zhilong, Li Zhen, Qi Tingye, Zhao Jiapeng, Fan Weichao, Yang Peng, Yang Xiaojun, Yu Yirui, Zhang Huifang, Wang Zhiwei
Summary: The influence of particle size on the re-crushing characteristics was investigated. It was found that particle size is closely related to the acoustic emission counts and energy. Crushed coal exhibits layered re-crushing characteristics, with larger particles experiencing more severe re-crushing. The screened results after final compression verify these characteristics.
Article
Engineering, Geological
Zhizhen Liu, Ping Cao, Qingxiong Zhao, Rihong Cao, Fei Wang
Summary: In the process of engineering construction involving tunnels and slopes, the impact of unloading rate on the stability of rock mass has been frequently ignored. This study conducted a series of uniaxial multi-level cyclic loading-unloading experiments to investigate the effect of unloading rate on the deformation behavior, energy evolution, and damage properties of rock-like material. The results showed that the unloading rate and relative cyclic number significantly influenced the deformation behavior and energy evolution of rock-like samples. A proposed damage model, accounting for the impact of the unloading rate and relative cyclic number, accurately predicted the damage caused by multi-level loading-unloading cycles in rock-like materials.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2023)
Article
Engineering, Civil
Xiaolin Deng, Shangan Qin, Jiale Huang
Summary: The crashworthiness of a new type of axially varying thickness lateral corrugated tube (AVTLCT) was studied under axial impact, showing that the PCF and CFE performance advantages are achieved with AVTLCT with k>0. The study also utilized a surrogate model and genetic algorithm for multiobjective optimization under unconstrained and constrained conditions.
THIN-WALLED STRUCTURES
(2021)
Article
Engineering, Mechanical
Shun Yang, Huang Yuan
Summary: A damage model for thermal barrier coatings was developed to quantify failure processes under isothermal and cyclic thermal loads. Different damage mechanisms were studied experimentally and computationally, with digital image correlation used to evaluate degradation. The model offers a general method to estimate remaining life based on quantifying complex damage.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Tinglian Zhang, Huang Yuan
Summary: The present study investigated the fatigue properties and crack growth of laser recasting materials using experimental and computational methods. The shielding effect observed is attributed to strength mismatch, leading to cyclic softening and mean stress relaxation in the under-matched recasting material. The recasting material exhibits higher crack nucleation resistance and lower crack growth rate compared to the base material, indicating that the weak recasting zone does not significantly impact the overall mechanical performance of the structure.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Aerospace
Tinglian Zhang, Kaiwen Guo, Jia Li, Huang Yuan
Summary: This study experimentally and computationally investigated the fretting fatigue crack growth of a nickel-based superalloy. The experiments revealed that the fretting fatigue cracks originated at multiple locations on the contact edge and propagated with a single through-thickness crack. The friction coefficient of the fretting pair influenced the kinking angle of the fretting crack. A methodology based on fracture mechanics was proposed to identify the friction coefficient on the fretting surfaces.
Article
Engineering, Mechanical
Cheng Luo, Huang Yuan
Summary: In this study, the anisotropic low cycle fatigue behavior of nickel-base single crystal superalloy was investigated in different crystal orientations. Fractography analysis revealed the activated slip systems under tension and a virtual resolved strain energy model was proposed to describe the anisotropic fatigue behavior.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Tinglian Zhang, Huang Yuan
Summary: This study investigated the mechanical properties and fatigue performance of laser melted mismatching nickel-base superalloys through multiscale experiments and computations. It was confirmed that the local strength degradation does not affect the macroscopic stress-strain responses and overall low-cycle fatigue performance due to the stress shielding in the remelting material. The stress shielding mechanism was quantitatively illuminated, and a critical shielding criterion was established.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Lihao Huang, Huang Yuan, Haiyan Zhao
Summary: Lattice metamaterials are increasingly used in weight-critical applications, and additive manufacturing technology provides more design freedoms. A new homogenization method based on finite element methods was proposed for accurate modeling of the mechanical behavior of complex microstructures. The mapping relation between lattice and finite element mesh, as well as edge effects, were clarified and modeled. The homogenization approach showed high numerical accuracy and outperformed the classical continuum model.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Cheng Luo, Huang Yuan
Summary: This research conducts multi-dimensional finite element modelings to investigate the effects of instrumented sharp indentation on materials with cubic symmetry. A novel reverse analysis algorithm is established to identify the elastoplastic properties of the cubic material, while the anisotropy of the material is determined through indentations on different orientations. The influences of elastic anisotropy and anisotropic yielding behavior are considered using three-dimensional computations. Sensitivity analysis confirms the accuracy and robustness of the new method, and the obtained results are compared and verified with experimental data of a nickel-base single crystal alloy.
MECHANICS OF MATERIALS
(2022)
Article
Engineering, Mechanical
Changhao Pei, Huang Yuan
Summary: This study investigated the anisotropic mechanical properties of IN718 superalloy in three different heat treatment states and three loading directions. The differences in mechanical performances were attributed to precipitation hardening and the impediment of dislocation motion from delta particles. Preferential epitaxial grain growth and resulting ⟨100⟩ texture were considered responsible for the anisotropic tensile strength. Weibull distribution and area-weighted grain diameter were used to characterize the grain distributions. Hall-Petch relation was established to correlate directional grain size and yield strength, illustrating the dominance of precipitates in strengthening mechanisms and the effects of subgrain boundaries.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Jiawei Xu, Huang Yuan
Summary: In recent investigations of thermal gradient mechanical fatigue (TGMF), it has been confirmed that the fatigue lives of materials are greatly affected by temperature gradients. Determining temperature gradients in thin-walled structures is always challenging. This study experimentally and computationally examined tubular specimens under different conditions. By improving the inverse heat conduction method, two models were developed that accurately predict temperature gradients in TGMF experiments with reasonable accuracy and versatility.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Industrial
Tinglian Zhang, Huang Yuan, Min Cai
Summary: The effects of recast layer on fatigue performance of laser-drilled holes in Ni-based superalloy were investigated experimentally and computationally. It was found that millisecond-laser drilling resulted in a recast layer of about 10 μm, while no recast layer was observed in the picosecond-laser drilled hole. The recast layer revealed Niobium segregation, Laves phase precipitation, and lattice distortions, leading to low yield stress. In-situ fatigue tests showed that the recast layer had no significant influence on the fatigue life of the holed structures in the low-cycle fatigue regime. Computational analysis confirmed that the recast layer reduced stress concentrations around the hole root, thus improving the fatigue performance of the mismatched material system.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Yujin Liu, Huang Yuan
Summary: In this paper, a hierarchical mechanism-informed neural network (HMNN) life prediction method was proposed. Fretting fatigue was addressed in four neural network layers, each focusing on a specific type of fatigue. The HMNN approach accurately predicts various kinds of fatigue and offers a new method for assessing complex fatigue.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Cheng Luo, Huang Yuan
Summary: This study investigated the thermomechanical fatigue behavior of nickel-base single-crystal superalloy with different crystal orientations. The crack initiation modes and damage mechanisms were characterized using SEM and optical microscopy. In IP-TMF, creep damage originated from casting pores and propagated under mode I. The creep facets were influenced by activated slip systems, while fatigue damage depended on crystal orientation and developed by slipping along different crystallographic planes. In OP-TMF tests, oxidation-assisted cracking was non-crystallographic for all crystal orientations, with the crack growing within the oxidized material.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Mechanics
Meiling Xu, Huang Yuan
Summary: This study investigates the crack-tip stress fields of elastoplastic fatigue crack growth with crack closure and their correlation to the Delta J-integral. The computational results show that the singularity of the effective stress ranges during the opening process decreases with increasing crack closure, while the effective stress ranges during the closing process follow the HRR solution form. The farfield Delta J(eff)-integral is proposed to characterize the stress at the crack tip during the closing process, which is independent of the loading ratio and the path dependence of the Delta J-integral. The proposed estimation formula for the effective Delta J(eff)-integral is applicable to different loading ratios and plastic hardening materials based on extensive FEM computations. The in-plane constraint effects in fatigue crack growth can be quantified using the J - Q concept of elastoplastic fracture mechanics within the framework of Delta J(eff)-Q characterization.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Jiaqi Lu, Huang Yuan
Summary: This study focuses on quantifying creep and oxidation effects to predict isothermal and thermomechanical fatigue life in a nickel-based superalloy. Creep damage was evaluated using the time-fraction method and the ductility-exhaustion method. A diffusion-dominated environmental damage parameter based on oxygen-assisted intergranular cracking mechanism was proposed and applied to thermomechanical fatigue life assessment. The results suggest that creep damage is negligible while environmental damage appears to be more dominant in this study. The proposed model provides a unified description for both isothermal and thermomechanical fatigue.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Engineering, Mechanical
Huanbo Weng, Huang Yuan
Summary: This study investigates the correlation between fabric tensor and anisotropic cyclic crystal plasticity of nickel-based single-crystal alloys using neural networks. Microstructural representative volume elements with different single crystal morphologies were generated, and their deformation behaviors were studied under different loading conditions. The results confirmed that the fabric tensor can describe the mechanical behavior and capture the history-dependent anisotropic cyclic hardening or softening behavior of the material.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Mechanics
Xiaolong Liu, Kelian Luo, Pengcheng Gao, Tao Cong, Xi Wang, Wenjing Wang
Summary: This paper investigates the formation mechanisms of the zig-zag crack region on the shattered rim of railway wheels. The zig-zag crack region, identified as a typical region for crack propagation in rolling contact fatigue behavior, was observed using scanning electron microscopy and transmission electron microscopy. The formation of the zig-zag morphology is attributed to the periodic deflection of the propagation path relative to the initial propagation plane, caused by the limited plastic deformation zone at the crack tip. Grain refinement and secondary cracks in the zig-zag crack region are a result of the large compressive and shear stresses induced by rolling contact loading.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Anastasia Iziumova, Aleksei Vshivkov, Ivan Panteleev, Virginia Mubassarova, Oleg Plekhov, Denis Davydov
Summary: The aim of this study was to investigate the correlation between structural, acoustic emission, and thermal characteristics of fatigue crack growth in titanium alloys. Cluster analysis of the acoustic emission signals revealed two different types of signals observed during the fatigue crack development. It was experimentally demonstrated that the stored energy tends to reach an asymptotic value at the final stage of fatigue crack growth and this is correlated with the twinning process intensification in titanium alloy Ti Grade 2. A correlation was assumed between the stages of change in heat flux, the cumulative energy of the first cluster of acoustic emission signals, and the crack length.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
M. Vieira de Carvalho, I. A. Rodrigues Lopes, F. M. Andrade Pires
Summary: This study investigates the numerical challenges of fracture mechanics models within implicit quasi-static frameworks and proposes an instability criterion. The ratio of cohesive to internal power is identified as a crucial factor. Two strategies for handling fracture problems with instabilities are discussed and a comparative assessment is performed. The study also examines more complex material responses, including transformation-induced plasticity effects.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Thomas Duminy, Aurelien Doitrand, Sylvain Meille
Summary: This study conducted in situ wedge splitting tests on millimeter-size PMMA samples and proposed a method to determine the material tensile strength and critical energy release rate using digital image correlation and a full finite element implementation of the coupled criterion.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Xin Chang, Xingyi Wang, Chunhe Yang, Yintong Guo, Yanghui Wan
Summary: The influence of cyclic thermal shock and high-temperature acid etching on the Mode I fracture of shale was investigated in this study. It was found that cyclic thermal shock severely degrades the strength and fracture toughness of shale, while high-temperature acid etching treatment improves the fracture toughness. These findings are valuable for optimizing process parameters to reduce initiation pressure in deep shale formations.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Liaojun Yao, Mingyue Chuai, Zhangming Lyu, Xiangming Chen, Licheng Guo, R. C. Alderliesten
Summary: Methods based on fracture mechanics have been widely used in fatigue delamination growth (FDG) characterization of composite laminates. This study proposes appropriate similitude parameters to represent FDG behavior with different R-ratios.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Zesheng Zang, Zhonghui Li, Yue Niu, Shan Yin
Summary: This study conducted experiments and recorded signals to investigate the fracture behavior and damage evolution characteristics of coal samples. The results showed that as loading proceeds, the stress, electric potential (EP), and acoustic emission (AE) values increase, and EP and AE signals are excited when stress drops. The fracture behavior of coal samples is altered by flaw inclination, and the destruction mode becomes increasingly complicated. The damage evolution characteristics of coal samples can be evaluated and analyzed by defining the coefficient of variation (CV value) of EP and the b value of AE.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Clotilde Berdin, Nathalie Prud'homme
Summary: In this study, zirconia layers with different fractions of tetragonal phase and thicknesses were tested for multi-cracking behavior. Cracks perpendicular to the tensile direction were observed, showing a blunting effect into the substrate. The ratio of crack spacing at saturation to layer thickness decreased as the layer thickness increased. Unit cell modeling was used to establish a relationship between crack spacing and layer strength, which fell within the bounds of Hu and Evans model and was found to be insensitive to the tetragonal zirconia fraction.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Huadong Zhang, Weichen Kong, Y. H. Liu, Yuh J. Chao
Summary: Williams' series expansion crack tip solution in linear elasticity is modified to include a uniform crack face pressure. Practical methods to calculate T-stress from near crack tip stresses are outlined. The analytical results are consistent with numerical results.
ENGINEERING FRACTURE MECHANICS
(2024)
Article
Mechanics
Jiahao Kong, Haoyue Han, Tao Wang, Guangyan Huang, Zhuo Zhuang
Summary: This paper introduces a phase-field model for polymer foam materials by combining the phase-field method with the crushable foam model. The model is calibrated using experimental data and successfully simulates the fracture processes of polyurethane under different loading conditions. The study is important for the engineering applications of polymer foam materials.
ENGINEERING FRACTURE MECHANICS
(2024)
