Article
Engineering, Mechanical
Li-Zhu Jin, Chang-Yu Zhou, Qi Pei, Yong-Sheng Fan, Le Chang, Xiao-Hua He
Summary: Crack sizes, geometrical configurations of specimens and structures, and loading conditions play a significant role in in-plane and out-of-plane constraint effects. Safety assessments with these constraint effects can significantly improve accuracy. The influence of biaxial compressive loading on fracture analysis with constraint effects is worth paying attention to, especially considering the significant impact of lambda on SIF, T-11, and T-33.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Mads Aursand, Bjorn H. Skallerud
Summary: This study investigates stress intensity factors for surface cracks with different geometries on curved round bars under various mode I stress distributions. Semi-analytical solutions for SIF at any point on the crack front are developed using finite element analysis and linear elastic fracture mechanics methods. Results demonstrate up to 8% difference in SIF values for cracks in curved bars compared to straight bars, with effects of relative bar curvature on numerical results being shown. The estimation of SIFs for cracks in a complex residual stress field is also demonstrated using a cubic polynomial stress approximation with an offshore mooring chain model as a case study.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Engineering, Marine
Jia-Rui Yuan, Hu Ding
Summary: In this paper, a dynamic model for the out-of-plane vibration of in-plane curved pipes conveying fluid is established for the first time. The governing equations of the out-of-plane vibration are derived analytically based on force analysis and fluid analysis. The critical velocity, natural frequencies, and modes of the curved pipe are calculated using the Galerkin truncation method. It is found that pipes with larger in-plane curvature have lower critical velocity for out-of-plane motion, and there is a significant decrease in natural frequencies with increasing curvature and fluid velocity.
Article
Engineering, Mechanical
Jung-Wook Wee, Alexander Chudnovsky, Byoung-Ho Choi
Summary: The study introduces a 2D CL growth model for semi-elliptical surface cracks in buried HDPE pipes, successfully simulating the SCG kinetics. Results show that the diameter of stones contacting the pipe surface influences crack propagation behavior and significantly reduces failure time.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Engineering, Mechanical
S. M. Tonge, Z. Chen, C. Meek, M. Mokhtarishirazabad, M. Mostafavi
Summary: The fracture load of a component is influenced by both the geometry and material properties, which are affected by the constraint on the plastic region near the crack tip. The constraint consists of in-plane constraint and out-of-plane constraint, determined by the size, geometry, and thickness of the component. Quantifying these constraints separately and simultaneously is possible, but few experimental studies have objectively compared their applicability, particularly for out-of-plane constraint. This paper presents the results of an extensive experimental program that examined the combined effects of in-plane and out-of-plane constraint using aluminium alloy specimens tested in a three-point bending configuration. The results showed variations in stress intensity factor K between 31 and 55 MPa·m^(1/2), depending on the level of in and out-of-plane constraint. The magnitude of the Q parameter and plastic zone volume increased with decreasing plastic constraint. Both Q and plastic zone volume were found to be suitable for quantifying the combined effects, but the uncertainty associated with the plastic zone volume was lower than that of Q.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Mechanics
Zheng Liu, Xin Wang, Ronald E. Miller, Jiaqi Hu, Xu Chen
Summary: Research on the fracture properties of 16MND5 steel under different constraint conditions showed that crack depth and specimen thickness have a significant impact on fracture properties. This study developed constraint dependent R-curves and initiation fracture toughness for the steel, as well as a new methodology to quantify the 3D constraint effect.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Engineering, Multidisciplinary
Y. Zheng, G. Z. Wang, S. T. Tu, F. Z. Xuan
Summary: The constraint and fracture initiation for semi-elliptical surface cracks in an actual large scale reactor pressure vessel (RPV) were studied using finite element analysis. The overall constraint level of the cracks was found to increase with increasing crack depth a/t and decreasing crack aspect ratio a/c. For most cracks, the constraint level was higher than that of the standard plane strain specimen, suggesting potential non-conservatism in conventional fracture assessment. The aspect ratio a/c had significant effects on the distributions of unified constraint parameters Ad* and elastic-plastic stress intensity factor KJ, as well as the fracture initiation position along the crack fronts.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2023)
Article
Engineering, Mechanical
Kuilin Yuan, Jiayun Liu
Summary: In this study, a new two-dimensional weight function for stress intensity factors of semi-elliptical surface cracks in finite-thickness and finite-width plates was proposed. The weight function was determined using parametric finite element models, and its accuracy was verified against existing solutions. This weight function can be used to calculate stress intensity factors and predict the fatigue life of engineering structural components with surface flaws.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Kresimir Jukic, Mato Peric, Zdenko Tonkovic, Ivica Skozrit, Tomislav Jarak
Summary: This study investigated the influence of residual stresses induced by buried-arc welding on crack behavior in steel plates through thermal-mechanical simulation and SIF calculation. The results showed good agreement between FE and WF methods for cracks perpendicular to the weld line at small sizes, with increasing deviation as crack size increased.
Article
Chemistry, Multidisciplinary
Aniket Patra, Vincenzo Caligiuri, Bruno Zappone, Roman Krahne, Antonio De Luca
Summary: Polaritons can be generated by tuning optical transitions and can have Epsilon-Near-Zero (ENZ) effective permittivity in dye-doped cavities. Spectral dispersion of polaritons in metal dielectric-metal (MDM) cavities was studied for different components of the incident wavevector. The results revealed a large Rabi splitting exceeding 100 meV and demonstrated the possibility of generating ENZ polaritons. The Surface Force Apparatus (SFA) was introduced as a powerful tool for characterizing strong light-matter interactions.
Article
Mechanics
Wei Guo, Wanlin Guo
Summary: This study systematically analyzed the ability of current elastic-plastic solutions to describe 3D constraints and their effects on the crack tip fields, specifically for corner and surface cracks emanating from stress concentrators. Through finite element method, good agreement was found between the 3D elastic-plastic solutions and FE results, showing their potential as a theoretical foundation for advanced damage-tolerant analyses of engineering structures.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Engineering, Mechanical
Weigang Wang, Wei Yang, Chun-Qing Li
Summary: This paper aims to determine a normalized fully plastic J-integral solution to mixed-mode fracture caused by inclined surface cracks, and develops a set of predictive formulas. The study finds that an increase in strain hardening exponent can increase the difference of normalized fully plastic J-integrals in pipes with different wall thicknesses.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Engineering, Mechanical
Bin Qiang, Hongkai Qiu, Yadong Li, Xin Wang, Guozheng Kang
Summary: This study derived weight functions for surface cracks in U-rib-to-deck joints, which accurately calculate the stress intensity factors (SIF). Different crack geometries were analyzed using the finite element method (FEM) to determine their effects on SIFs, and new weight functions were developed and validated. The proposed weight functions were able to calculate the SIFs for surface cracks in U-rib-to-deck joints, accounting for welding residual stresses, and were compared to existing methods.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Engineering, Multidisciplinary
Li Dong-fang, Mao Zhao-hui
Summary: A numerical model based on the theory of elastic fracture was developed to solve the composite stress intensity factor of semi-elliptical cracks on exchanger outer walls with inclined angles. The results of the study are important for evaluating the remaining life of exchanger components.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Mechanics
Xingling Huang
Summary: A new analytical solution for plastic zone size is proposed for mixed mode I/II cracks using the von Mises yield criterion, and the theoretical relationship between plastic zone size and in-plane and out-of-plane T-stresses is determined. Three constraint parameters are derived from plastic zone sizes and area, and the influences of T-stresses and mode mixity on plastic zones are investigated. The combined effects of in-plane and out-of-plane T-stresses on fracture toughness are analyzed, and linear correlations between constraint parameters and fracture toughness are observed.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
F. Chen, G. Z. Wang, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2018)
Article
Materials Science, Multidisciplinary
Xiaomin Tan, Guozhen Wang, Shantung Tu, Fuzhen Xuan
MATERIALS AT HIGH TEMPERATURES
(2019)
Article
Engineering, Multidisciplinary
X. M. Tan, G. Z. Wang, S. T. Tu, F. Z. Xuan
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2019)
Article
Mechanics
Y. H. Wang, G. Z. Wang, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2019)
Article
Mechanics
X. M. Tan, G. Z. Wang, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2019)
Article
Mechanics
K. Wang, G. Z. Wang, X. M. Tan, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2020)
Article
Mechanics
J. Y. Xiao, G. Z. Wang, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2020)
Article
Engineering, Multidisciplinary
Y. H. Wang, G. Z. Wang, S. T. Tu, F. Z. Xuan
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2020)
Article
Engineering, Mechanical
X. M. Tan, G. Z. Wang, S. T. Tu, F. Z. Xuan
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2020)
Article
Mechanics
K. Wang, G. Z. Wang, S. T. Tu, F. Z. Xuan
ENGINEERING FRACTURE MECHANICS
(2020)
Article
Engineering, Mechanical
Yuhan Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2020)
Article
Engineering, Mechanical
Kai Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
Summary: This paper investigates the effects of crack sizes, plate geometries, and material properties on the creep fracture mechanics parameter C* for plate structures with semi-elliptic surface cracks under different loads. Creep influence functions Hc were obtained to calculate C* values, which were fitted into equations and verified through finite element calculations. The solutions for C* obtained from these equations are suitable for various crack sizes, plate geometries, and materials.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Kai Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
Summary: In this study, the authors investigated the unified creep constraint parameter for plate structures with different surface crack sizes using finite element analysis. They analyzed the effects of material properties, crack sizes, loading modes, and plate thickness on the parameter and proposed a method for assessing the life of cracked plates.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Jinyong Xiao, Guozhen Wang, Fuzhen Xuan, Shantung Tu
Summary: In this study, the relationship between ductile fracture toughness and a new unified constraint parameter A(d)* for bi-material interfaces with different mechanical mismatches was investigated. The results showed that both increasing crack depth and mechanical mismatch level led to a decrease in the J-R curves and fracture toughness of bi-material interfaces. A general correlation equation between fracture toughness and constraint parameter was obtained, which can be used to predict fracture toughness in different material and geometric constraint situations.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(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)