Article
Engineering, Mechanical
Monika Duda, Dariusz Rozumek, Michal Smolnicki, Anna Wybraniec
Summary: The article discusses the results of a study on fatigue fracture in mixed and I + II and I + III modes in heat treated steel 42CrMo4. It presents different mechanical properties resulting from various thermal treatments and demonstrates tests conducted on different sample types and load angles. The research aims to enhance understanding of fatigue crack development under mixed modes and provide valuable insights into the material's behavior under complex loads.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Shiv Sahaya Shukla, K. S. R. K. Murthy, S. Sajith
Summary: In this work, mixed mode (I/III) fracture behavior was investigated using a new specimen and an out-of-plane loading fixture compatible with conventional uniaxial universal testing machines. The proposed specimen, a single edge cracked circular (SECC) specimen, can be used for metallic and non-metallic materials under static and fatigue loads. Finite element analyses and experimental fracture studies were conducted, showing good agreement with existing mixed mode (I/III) fracture criteria. The results indicate that the pure mode III fracture toughness is 1.46 times greater than that of mode I, attributed to an increase in the inelastic region around the crack tip. Fractured surface analysis revealed rougher surfaces with increasing mode III component. Preliminary fatigue crack growth studies on Al 7075-T6 using the SECC specimen were also presented, confirming the applicability of the proposed setup for studying mixed mode fracture behavior under static and fatigue loading.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Engineering, Mechanical
Zhida Ren, Beizhi Li, Qingzhi Zhou
Summary: This study investigates the damage caused by rolling contact fatigue (RCF) and the propagation of fatigue cracks in bearings. Through experiments and statistical analysis, the three-dimensional geometry of RCF cracks was characterized and reconstructed. Finite element analysis and numerical studies were conducted to reveal the crack propagation behavior and mechanisms on the contact surface and subsurface.
Article
Mechanics
Shiv Sahaya Shukla, S. Sajith, K. S. R. K. Murthy
Summary: A simple and efficient specimen geometry for mixed mode (I/II) fracture tests and fatigue crack growth studies has been proposed in this investigation. Through extensive finite element analyses and experimental studies, the proposed specimen geometry shows good agreement with widely used fracture criteria in terms of fracture toughness, indicating its practicality.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2022)
Article
Materials Science, Multidisciplinary
Monika Duda, Dariusz Rozumek, Grzegorz Lesiuk, Michal Smolnicki, Bartosz Babiarczuk, Joanna Warycha
Summary: This paper presents the results of an experimental investigation on fatigue crack development in heat-treated 42CrMo4 steel under mixed-mode I + II and I + III. The tests were conducted using compact tension shear specimens and rectangular cross-section specimens for mixed-mode I + III. The paper also discusses the fracture analysis results of fatigue crack path development.
INTERNATIONAL JOURNAL OF FRACTURE
(2022)
Article
Mechanics
Rathin Maity, Akhilendra Singh, Surajit Kumar Paul
Summary: This study experimentally investigates the onset of fast fracture and crack deflection in AA 7085 for both mode-I + III and mode-II + III fracture modes. A new loading device has been developed to induce out-of-plane mode in addition to mode-I and mode-II loading. The crack deflection angle and fracture envelope were compared against standard criteria to predict failure.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Qikun Xie, Hongyu Qi, Shaolin Li, Xiaoguang Yang, Duoqi Shi
Summary: One of the most common damage modes of aero-engine hot-end components is crack, which is typically in a mixed-mode and under elastoplastic conditions due to the complicated geometry and harsh working environment. The phase-field fracture method has recently attracted extensive attention as a numerical simulation method. However, attention toward material damage and crack initiation before the crack emerges is lacking in solving the problem of elasto-plastic mixed-mode fatigue crack propagation. In this study, an enhanced phase-field fracture method is used to address this issue and predict the propagation behavior of the elastoplastic mixed-mode fatigue crack. The effect of some parameters of this model is analyzed. This achievement is a significant contribution to the safety of aircraft engines and a novel method that can be further improved to solve problems in the future.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Miao Xinting, Jiang Chenyang, Zhou Changyu, Peng Jian, Gao Guangfan
Summary: This paper investigates the effects of specimen type and thickness on fracture parameters for mixed mode cracks, showing the significant impact of coupling effect and mode I component on crack tip field and fracture behavior. It is suggested that a new mixity parameter considering the coupling effect is needed to describe mixed mode cracks accurately. Additionally, the paper emphasizes the influence of specimen type over thickness on constraint for mixed mode cracks.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Mechanics
L. Wang, Y. J. Xie, H. Yuan
Summary: The potential fracture configurations of a cracked solid under mixed Mode-I/III loading were investigated using a three-dimensional energy-based model, which effectively captured the physical process of energy release induced by multiple cracks initiation. Four integral subintervals for J(i)-integral around a crack tip were suggested to maximize the energy release rate, and the four concerned energy-based driving forces were identified. The results theoretically predicted various potential fracture configurations for cracked solids under the mixed Mode-I/III loading, and agreed well with experimental results.
ARCHIVE OF APPLIED MECHANICS
(2023)
Article
Mechanics
Wei Liu, Yulong Li, Zhiqian Zhang, Liyun Yang, Yi Luo, Zhongwen Yue
Summary: This study investigates the mixed-mode I+II fracture characteristics of V-notched rock specimens under impact loads, considering the effects of loading rate, notch angle, and loading angle. Experimental and numerical analysis results show that loading rate has a significant positive effect on the fracture toughness value, but has a negative effect on the crack initiation angle.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Georgios Kotsinis, Theodoros Loutas
Summary: This work presents an analytical solution for calculating the total strain energy release rate and mode partitioning of a beam-type delamination specimen under high speed, mixed-mode loading. The dynamic response of a Mixed-Mode End Load Split specimen subjected to loading with a constant velocity is modeled using the Timoshenko beam theory. A Virtual Crack Closure Technique is used for mode partitioning, and a Lagrangian multiplier method is used to model the bonded region. The specimen is treated as a waveguide, and the allowed propagating waves are analytically obtained. Due to the complex form of the wavenumbers for the bonded region, a series approximation method is applied. The proposed analytical solution is validated using a 2D Finite Element Model, and the results demonstrate the dependency of the Strain Energy Release Rate and mode mixity on the eigenfrequencies and eigenmodes of the specimen, resulting in inconsistent mode mixity values over time.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Ali O. Ayhan, Oguzhan Demir
Summary: The study conducted experiments and numerical simulations on mixed mode I/II/III fatigue crack growth, evaluating a new 3-D fracture criterion for its applicability in 3-D mixed mode fatigue problems. The developed criterion showed better predictability for crack growth surface under highly mixed mode conditions, reducing deviation from experimental surface compared to other criteria.
COMPUTERS & STRUCTURES
(2021)
Article
Engineering, Mechanical
Reza Jalayer, Behnam Saboori, Majid Reza Ayatollahi
Summary: A new test specimen is proposed for investigating mixed mode I/II/III fracture of materials. This test specimen creates mixed mode I/III loading conditions by displacing the position of an inclined crack from the middle of the rectangular specimen, in addition to mode II loading under anti-symmetric four-point bending. The experimental fracture loads of PMMA specimens are compared with theoretical predictions, showing satisfactory consistency.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Xiushuo Zhang, Yu' e Ma, Meng Yang, Wei Huang, Yilin Peng, Zhenhai Wang
Summary: Residual stress significantly affects fatigue performance in friction stir weld (FSW) joints. This study investigates the effect of biaxial residual stress components on mixed-mode crack propagation behavior in FSWed 7075-T6 fuselage panel through experiments and numerical simulations.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Anja Gosch, Florian J. Arbeiter, Michael Berer, Tomas Vojtek, Pavel Hutar, Gerald Pinter
Summary: The study found that fatigue loading of polymers in pure mode I and mixed mode I/III led to fluctuations in lifetime, depending on the levels of applied loading. Fracture surface morphology revealed the critical influence of friction and localized temperature increase on fatigue fracture behavior.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Energy & Fuels
Hossein H. A. Alizadeh, Rahman Seifi, Seyed Abbas Radmard
Article
Engineering, Mechanical
Rahman Seifi, Kaveh Abbasi, Masood Asayesh
IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY-TRANSACTIONS OF MECHANICAL ENGINEERING
(2018)
Article
Engineering, Mechanical
R. Hosseini, R. Seifi
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2019)
Article
Engineering, Mechanical
R. Seifi, M. A. Kazemi
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2018)
Article
Metallurgy & Metallurgical Engineering
Rahman Seifi, Mohammad Reza Mohammadi
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2018)
Article
Engineering, Marine
Rahman Seifi, Milad Ranjbaran
SHIPS AND OFFSHORE STRUCTURES
(2019)
Article
Engineering, Mechanical
Mohammad Reza Mohammadi, Rahman Seifi
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2018)
Article
Engineering, Mechanical
Milad Ranjbaran, Rahman Seifi
JOURNAL OF STRAIN ANALYSIS FOR ENGINEERING DESIGN
(2020)
Article
Engineering, Mechanical
Rahman Seifi, Mostafa Bahri
JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING
(2019)
Article
Engineering, Mechanical
Mohammad Reza Mohammadi, Rahman Seifi
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2019)
Article
Materials Science, Multidisciplinary
M. A. Salevati, A. Imam, R. Seifi, F. Akbaripanah
Summary: This study demonstrates that the microstructure and mechanical properties of AZ80 magnesium alloy can be significantly improved by adding nanoparticles and increasing the number of DECLE passes. The grain size decreases significantly with the increase in pass numbers, leading to improved hardness and tensile strength.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Engineering, Mechanical
Reza Hosseini, Rahman Seifi
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2020)
Article
Horticulture
Ebrahim Chavoshi, Ebrahim Ahmadi, Ali Alavi Nia, Rahman Seifi
Summary: This study investigates the dynamic deformation behavior and surface temperature changes of apples under impact loads using finite element simulation. The results show that force-time data offers better results than velocity-time data in dynamic simulation. The surface temperature of the bruised area is lower than that of the healthy area. The volume of bruising is directly related to the impact surface and the radius of curvature and inversely related to the apple temperature.
SCIENTIA HORTICULTURAE
(2023)
Article
Engineering, Mechanical
Erfan Kakavand, Rahman Seifi, Mostafa Abolfathi
Summary: This study evaluates the effects of mechanical load frequencies and thermal fluctuations on the fatigue crack growth in CT samples made by AA7075-T6. The results showed that increasing the constant temperature reduces the fatigue lives of the samples. Numerical simulations indicated that reducing the load frequency has little impact on the fatigue crack propagation behavior, while further reduction severely decreases the failure cycles.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Rahman Seifi, Mohammad Asadi
Summary: The effects of dimensions, position, and depth of subsurface cracks on stress intensity factors of sliding (K-II) and tearing (K-III) modes were investigated in railway systems. The variations of K-II and K-III values with wheel rolling angles and frictions were considered. The validity and accuracy of the cracked model created by sub-modeling technique were verified by half-space modeling and weight function method.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Marine
Chunhao Jiang, Lin Lin, Nian-Zhong Chen
Summary: A novel type of side structure for enhancing the crashworthiness of double-hull vessels is proposed based on auxetic materials. Numerical simulation demonstrates the resistance to collision of three different unit cells. A comparative study shows that the proposed side structures have superior energy absorption and collision resistance compared to traditional side structures.
Article
Engineering, Marine
Lihua Xu, Jiasong Wang, Michael S. Triantafyllou, Dixia Fan
Summary: This paper presents a data assimilation method based on the POD-DeepONet structure to fuse two types of fidelity data from vortex-induced vibration (VIV) problems. The POD-DeepONet structure provides better accuracy and more stable predictions for amplitude response, successfully capturing the changing trend with the oncoming flow speed. The exponentially fitted MSE formula allows for quick determination of the required case number under the expected error.
Article
Engineering, Marine
Ilias Gavriilidis, Aris G. Stamou, Christos Palagas, Efthimios Dourdounis, Nikos Voudouris, Athanasios Tazedakis, Spyros A. Karamanos
Summary: This study investigated the collapse resistance of thick-walled steel pipes fabricated with the JCO-E process for deep offshore applications. It conducted a comprehensive analysis using experimental, numerical, and analytical approaches to examine the effects of heat treatment on the collapse behavior of two JCO-E pipes. The results were compared with the predictions of the DNV-ST-F101 standard, and the fabrication factor afa was discussed. The study also explored the impact of yield strength recovery due to heat treatment on the collapse of pipes with different D/t ratios.
Article
Engineering, Marine
Sung-Jae Kim, Chungkuk Jin, MooHyun Kim
Summary: This study evaluates the effects of tsunami waves on the global performance of a spread-moored Floating Storage Unit (FSU) through tsunami-floater-mooring coupled dynamics simulations. The results show that larger tsunami heights and relatively short durations result in significantly increased motions and mooring tensions of the FSU.
Article
Engineering, Marine
Ling Zhu, Zhihui Zhou, Preben Terndrup Pedersen
Summary: Ship grounding experiments are crucial for validating numerical analysis and theoretical formulations. In this study, small-scale ship model grounding tests on a sharp rock were conducted in a water tank to observe and record different damage modes, ship bottom plate damage extents, and ship motion. The test results were used to analyze the energy dissipation process and the influence of initial conditions on ship response and damage.
Article
Engineering, Marine
Zhiping Zheng, Yanlin Shao, Jikang Chen
Summary: This study investigates the effect of horizontal low-frequency (LF) displacements and velocities on the responses of floating structures in irregular waves, focusing on a deep-draft spar buoy. The study finds that incorporating LF displacements and velocities in the seakeeping analysis is essential for reducing surge and pitch responses. The standard deviations of LF surge and pitch motions scale with significant wave height, highlighting viscous damping as the dominating damping mechanism.
Article
Engineering, Marine
Birendra Chaudhary, Hewenxuan Li, Akongnwi Nfor Ngwa, Helio Matos
Summary: This study investigates the long-term performance and effectiveness of coating systems for 3D-printed pressure vessels subjected to accelerated aging. The results show that the application of polyurethane coating systems significantly slows the degradation process, reducing critical operational depth and increasing pressure differential. This research contributes important insights into enhancing the longevity and performance of 3D-printed pressure vessels through coating systems.
Article
Engineering, Marine
Yuelin Song, Qin Dong, Jiping Zhang, Guoqiang Li, Dongfang Xu, Ping Yang
Summary: The objective of this research is to study the characteristics of low-cycle fatigue crack propagation from the perspective of accumulative plastic damage and propose a reliable prediction model for crack growth in EH-36 steel under high stress levels. Experimental findings demonstrate that increasing the mean stress and stress amplitude accelerates the progression of fatigue damage.
Article
Engineering, Marine
Hao Ding, Bo Huang, Liang Cheng, Ke Li, Qingyang Ren
Summary: This study investigates the dynamic response and cable forces of a submerged floating tunnel (SFT) under wave and wave-current interactions. Experimental results show that wave height, current velocity, and ratio of wavelength to structure size are important factors affecting the dynamic response of SFT and cable forces. The multi-anchor cable arrangement used in the experiments distributes cable forces more effectively and reduces potential safety hazards caused by cable breakage.
Article
Engineering, Marine
Baoshun Zhou, Zhixun Yang, Mostafa Amini-Afshar, Yanlin Shao, Harry B. Bingham
Summary: In the hydroelastic analysis of large floating structures, accurate prediction of response relies on the structural stiffness. However, obtaining exact structural stiffness is challenging due to the complexity of modern ship structures. This study proposes an efficient analysis technique that combines finite element and finite difference methods to calculate structural stiffness and solve hydrodynamic problems.
Article
Engineering, Marine
Xinwei Chen, Yang Yu, Lei Wang
Summary: This study introduces a framework to evaluate and compare scour prediction models, focusing on design robustness. By applying this framework, the study recommends the most favorable scour prediction model and optimal design for monopiles in OWTs.
Article
Engineering, Marine
Yu Lei, Wei Li, Xiang Yuan Zheng, Huadong Zheng, Shan Gao, Shengxiao Zhao
Summary: This paper compares the numerical results of a floating offshore wind turbine integrated with a steel fish farming cage (FOWT-SFFC) against experimental data. The study shows that the simulated responses are in good agreement with the experimental data and reveals the important influence of second-order wave forces on the simulation results.
Article
Engineering, Marine
Chenyu Luan, Torgeir Moan, Knut Andreas Kvale, Zhengshun Cheng
Summary: This paper deals with the study of the shear lag effect on the bending moment distribution in pontoon-type floating bridges. Comparative and parametric studies are carried out using beam and linear shell models to analyze the influence of shear lag on the bending stiffness and eigenmode shapes of the bridges. The study shows that elementary beam models may inaccurately predict the bending moments in bridges with large width and short span lengths, and a practical method is proposed to determine when caution is needed in using these models. The paper also highlights the complex boundary conditions near the bank abutment and the significant influence of shear lag on the bending moments in this region.
Article
Engineering, Marine
Akira Tatsumi, Yuji Kageyama
Summary: This study proposes a methodology to quantify the uncertainty of the ultimate strength of stiffened panels in steel ships and offshore structures due to the welding initial deflection. A statistical model of the initial deflection shape is developed based on measured data, and probability distributions of the ultimate strength are calculated using Monte Carlo simulation.
Article
Engineering, Marine
Zhenmian Li, Yang Yu, Xin Liu, Xiaowei Liu, Xiangyang Wang, Leige Xu, Jianxing Yu
Summary: This study evaluates the local collapses and propagating buckles of offshore pipelines under external overpressure, reverse fault displacements, and collapse failures. Different designs of integral arrestors are tested in a numerical model, and the effects of fault dip angles are investigated. The results show that integral arrestors are effective in preventing propagating buckles.
