Article
Engineering, Multidisciplinary
Xuran Xiao, Volodymyr Okorokov, Donald Mackenzie
Summary: This paper proposes a method for predicting the high cycle fatigue life of cyclically loaded components with induced residual stress using standard S-N curve data, a fracture mechanics crack growth model, and Finite Element Analysis. The method is suitable for components with linear elastic working stress cycles and satisfying the requirements of LEFM and the SMART FEA method. The total fatigue life of the component is calculated by summing up the crack initiation life and crack propagation life.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2023)
Article
Engineering, Mechanical
Mohit Goswami, Sujit Sharma, Soumya Roychowdhury, Stephane P. A. Bordas, Santanu Chattopadhyay
Summary: Comparative investigation was conducted on carbon black and silica-filled natural rubber composites, revealing that silica-filled rubber composites with 16 wt% silane loading demonstrated optimum mechanical and fracture properties, while carbon black exhibited better reinforcing efficacy after 300% elongation. Experimental investigations and finite element analysis showed a decrease in J-integral with increasing crack opening angle, with a 22% decrement observed for rubber composites with a pre-crack length of 5 mm when the crack opening angle varied from 300 to 600. The geometry factor was dependent on the type of filler when the crack opening angle was increased for composites with a large pre-crack length. This study is expected to be useful in rectifying design faults of different rubber composites used in industrial applications, particularly passenger and heavy-duty tires.
ENGINEERING FAILURE ANALYSIS
(2023)
Article
Mechanics
Chen Huang, Ye Song, Liyun Yang, Ping Fan, Qingcheng Wang, Huizhen Liu
Summary: This paper investigates the fracture behavior of TPB beams with V-notches under mode I and mixed mode I-II loading. An experimental system combining 3D-DIC and a new digital laser caustic is established to measure the Notch Stress Intensity Factors (NSIFs). The effects of eccentric loading and the rotation angle of V-notches on initiation and propagation are analyzed. A Maximum Tensile Stress (MTS) criterion suitable for V-notches is proposed and validated.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Civil
Wei Shen, Guiming Liang, Jiajing Lei, Chunmei Li
Summary: This study derived a simplified formula for calculating the notch stress distribution and N-SIF of double edge V-notch plate based on linear elastic fracture mechanics and singular strength theory. The evaluation formula of notch stress field was simplified by introducing the singular intensity factor 'as' and extended to arbitrary opening angles. The simple formula proposed showed high accuracy in calculating N-SIF across a wide range of opening angles and geometric sizes, making it convenient for engineering applications.
THIN-WALLED STRUCTURES
(2021)
Article
Engineering, Mechanical
Fengjin Zhu, Hongyan Liu, Leihua Yao, Gang Mei
Summary: This study investigates the mechanical behavior of a closed crack under uniaxial compression and finds that there is no K-I singular term at the crack tip, while K-II and T-stress are influenced by the effective shear stress. Experimental validation of the theoretical predictions is done using isochromatic fringe patterns.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Mechanics
Wei Liu, Chunyang Hu, Longkang Li, Xiaofei Zhang, Linzhi Peng, Yaxu Qiao, Zhongwen Yue
Summary: The study investigated the dynamic notch fracture toughness of V-notched rock specimens using empirical formulas, SHPB tests, DIC method, and mean stress criterion. These proposed methods have significant applications in evaluating fractures in rock structures compromised by notches.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Ceramics
Ana C. C. Trindade, Pengqing Wang, Waltraud M. Kriven
Summary: This work presents a systematic study on the shear properties of a potassium-based geopolymer reinforced with different types of fibers. Chopped fibers showed significant improvement in shear strength and shear modulus, while thicker fibers and steel fibers exhibited better performance in shear strain. Sand-coated fibers and mini rods had inferior performance, but their shear stress could be increased by adjusting the manufacturing process.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Engineering, Geological
Wei Liu, Zhiqian Zhang, Weixian Cheng, Xiaofei Zhang, Zhongwen Yue, Zhaoyang Ma
Summary: This paper investigates the dynamic fracture resistance of blunt V-notched rock samples using experimental and theoretical methods. The results show that the dynamic fracture resistance depends on the opening angle, notch radius, and loading rate. Additionally, a modified mean stress criterion is proposed to assess the dynamic fracture onset, which agrees well with experimental data.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Engineering, Mechanical
Yingzhi Li, Petr Dymacek, Roger Hurst, Paul Stevens
Summary: The research proposes a novel methodology to derive the key parameter C*-integral for notched small punch specimens directly without relying on known CT tests. By establishing a 3D finite element model and conducting experiments, the key parameter C*-integral is obtained for determining material properties related to creep crack initiation and growth.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Construction & Building Technology
Fengjun Lv, Wanzhen Wang, Wei Zhao
Summary: In this study, 20 fatigue tests were conducted on notched plates of Q460C steel to examine the effects of relative stress amplitude, Delta sigma/f(y), and relative nominal maximum stress, sigma(max)/f(y), on the fatigue life of these notched plates. Theoretical analyses and numerical simulations based on an ellipsoidal fracture model were used to investigate fatigue cracking in the Q460C steel notched plates. The unified crack growth approach was further developed to estimate the fatigue life of the Q460C steel notched plates, and its accuracy was assessed compared to the recommended fatigue life formula in China's code GB50017-2017. The results indicate that the unified crack growth approach provides a reliable assessment of fatigue life for the Q460C steel notched plates.
Article
Polymer Science
Robab Bahadori, Majid Reza Ayatollahi, Sergio Cicero, Jose Alberto Alvarez
Summary: This paper presents experimental and theoretical investigations on the fracture initiation angle and fracture strength in VO-notched PMMA specimens under mode I loading conditions. The study found that crack propagation does not necessarily occur along the notch bisector line, and predictions using the GMTS criterion showed satisfactory consistency with experimental results.
Article
Mechanics
Yongyu Yang, Changzheng Cheng, Zhongrong Niu, Zongjun Hu
Summary: This study examines the free vibration analysis for the moderately thick V-notched plate based on Mindlin's first-order shear deformation theory. The Ritz method is employed with the introduction of singularity characteristic angular functions to improve the accuracy and convergence of the frequency calculation. The results show that the notch opening angle and relative thickness have a significant effect on the frequency, and the influence of the boundary conditions differs between clamped and free edges for the V-notch.
Article
Engineering, Mechanical
M. F. Borges, F. V. Antunes, D. M. Neto, J. M. Vasco-Olmo, F. A. Diaz, M. N. James
Summary: This paper proposes a method based on crack tip opening displacement (CTOD) to define the boundary of the small-scale yielding (SSY) regime. Numerical modeling was conducted on samples with different notch radii and under different stress conditions. The results show that the validity of SSY is promoted with increasing notch radius, but decreases with increasing crack length, particularly in notched specimens. Most of the cases studied do not fall within the SSY regime, emphasizing the importance of verifying the applicability of Linear Elastic Fracture Mechanics (LEFM) for fatigue crack growth rate calculations.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Engineering, Mechanical
Ramy Gadallah, Hidekazu Murakawa, Kazuki Ikushima, Masakazu Shibahara, Seiichiro Tsutsumi
Summary: The study used elastic-plastic numerical calculations to investigate the effect of specimen thickness and stress level on fatigue crack growth rate in notched mild steel specimens. The results showed that thinner specimens exhibited faster crack growth rates when stress level is close to general yield, while the effect of thickness on crack growth rate at the mid-thickness was not significant below general yield stress levels. The crack-tip driving force Delta J and local strains and stresses played a key role in explaining the behavior of FCGR under different thicknesses and stress levels.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2021)
Article
Mechanics
Yifan Huang, Xin Wang
Summary: This study utilized 2D FEA to evaluate key parameters for fracture toughness testing on orthotropic materials, developing accurate regression solutions and applying them to experimental data for further discussion. The research outcome is expected to benefit the standardization of fracture toughness testing on orthotropic composite materials.
COMPOSITE STRUCTURES
(2022)
