Article
Engineering, Mechanical
L. Chen, R. de Borst
Summary: This article introduces the modeling of discrete interfaces in the phase field regularization framework and compares the applicability of different phase field models. The method combines the advantages of discrete and smeared approaches to improve the accuracy of interface modeling. The effectiveness of the method is demonstrated through several numerical examples.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Ali Harandi, Shahed Rezaei, Soheil Karimi Aghda, Chaowei Du, Tim Brepols, Gerhard Dehm, Jochen M. Schneider, Stefanie Reese
Summary: In this study, a numerical framework is developed to predict fracture in ceramic thin films. The cohesive phase-field damage model is used to consider the fracture energy and material strength. The orientation of grain morphology and the microstructure are found to affect cracking behavior, and an equivalent fracture energy is introduced to account for these effects. Tensile tests on different thin films are performed to evaluate the accuracy of the proposed model. The study provides insights into the effect of material parameters on thin film damage behavior, including ultimate strength, fracture energy, and residual stress.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Pranavi Dhaladhuli, Rajagopal Amirtham, Junuthula N. Reddy
Summary: A thermodynamically consistent phase field formulation is presented for modeling the interactions between interfacial damage and bulk brittle fracture. A novel nonlocal approach is devised to evaluate the smoothened values of jump at the regularized interface, resulting in a more realistic mechanical response of any composite system and accurately representing various failure modes.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2022)
Article
Engineering, Multidisciplinary
Keita Yoshioka, Mostafa Mollaali, Olaf Kolditz
Summary: This paper proposes a diffused approach to approximate failure at interfaces with negligible space, deriving an effective interface fracture toughness and verifying its effectiveness in various scenarios.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Chemistry, Physical
Mingjun Peng, Renfu Wang, Longke Bao, Yonghua Duan
Summary: The study systematically explored the atomic structure, adhesion work, interfacial energy, and fracture mechanism of the semi-coherent Al(111)/Al3BC(0001) interface using first-principles calculations. It was found that the B-terminated Al(111)/Al3BC(0001) interface in HCP2 configuration exhibits the highest adhesion work and lowest interfacial energy, indicating its stability. The formation of strong Al-B covalent bonds at the interface ultimately leads to mechanical failure in the Al slab at the B-HCP2 interface.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Avtar Singh, Siladitya Pal
Summary: The evolution of complex fracture patterns during electrochemical cycling is an important factor contributing to capacity fading in polycrystalline particulate cathodes of lithium-ion batteries. This study develops a thermodynamically consistent multi-physics modeling framework to understand the fracture mechanisms in these cathodes under chemo-mechanical environments. The framework incorporates fracture energies of grains, grain boundaries, and particle-matrix interfaces and solves coupled governing equations for concentration, displacement, and phase-field damage to investigate the effect of various parameters on the chemo-mechanical behavior, fracture evolution, and electrochemical response.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)
Article
Chemistry, Physical
Weilong Ai, Billy Wu, Emilio Martinez-Paneda
Summary: This study develops a multi-physics phase field fatigue model to study crack propagation in battery electrode particles. By coupling with X-ray CT imaging, fatigue cracking of realistic particle microstructures is simulated. Non-linear crack propagation behavior is predicted, with an exponential increase in cracked area observed with cycle number. Three stages of crack growth and phenomena such as crack initialization at concave regions and crack coalescence are observed. The critical values of C-rate, particle size, and initial crack length are determined.
JOURNAL OF POWER SOURCES
(2022)
Article
Materials Science, Multidisciplinary
Jihai Yuan, Lei Wang, Changping Chen
Summary: In this work, an interfacial debonding phase field model is established to simulate the interfacial fracture behavior of highly heterogeneous solids. The model has the following novelties: (1) smearing the interface properties to eliminate singularity; (2) regularization of the critical energy release rate of the interface by adjusting the characteristic length scale parameters; and (3) prediction of complex cracking phenomena such as multiple crack initiation, merging, and branching. The proposed model is experimentally and numerically validated, and the influence of interface properties on fracture behavior is studied in detail. It has the potential to predict interfacial debonding and crack kinking path in complicated quasi-brittle heterogeneous materials.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Arezoo Emdadi, Mohsen Asle Zaeem
Summary: A phase-field model based on a modified form of Griffith's fracture theory is proposed to study intergranular and transgranular crack propagations in polycrystalline brittle materials. By incorporating grains and grain boundaries into the crack initiation and propagation model, the strength and crack surface energy along the grain boundaries can be controlled, which affects the fracture toughness of the material. Specific combinations of grain boundary strength and crack surface energy can promote intergranular crack propagation and enhance the fracture toughness of polycrystalline materials.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Hui Ruan, Shahed Rezaei, Yangyiwei Yang, Dietmar Gross, Bai-Xiang Xu
Summary: Thermal fracture is a common and devastating defect in metal additive manufacturing. This study proposes a thermo-mechanical phase-field fracture model based on a thermodynamically consistent derivation. The model considers different coupling terms, fracture formulations, and thermomechanics information. The finite element method is used for numerical implementation, and the model is applied to simulate hot cracking in additive manufacturing considering thermal strain and solidification shrinkage. The study reveals the dominant roles of solidification shrinkage strain and temperature gradient in crack formation and provides insights into process parameter effects on crack types. The numerical predictions of crack patterns are in good agreement with experimental observations, demonstrating the capability of the model.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Materials Science, Multidisciplinary
Laishan Yang, Jing Yang, Fang Han, Zhihang Zhang, Qinghua Li, Zhibo Dong, Lei Wang, Nana Ofori-Opoku, Nikolas Provatas
Summary: Hot cracks are a common defect in casting, welding, and additive manufacturing. Despite the key role of grain boundaries in hot cracking formation, their effects are often overlooked. This study focuses on simulating grain boundaries and investigating the relationship between hot cracking susceptibility and solute concentration.
Article
Thermodynamics
Shahab Mirjalili, Suhas S. Jain, Ali Mani
Summary: This article discusses the interface transfer issue in two-phase flows involving heat/mass transfer. Two models are proposed to address the challenge of the undefined interface in phase field models, and their consistency, accuracy, and convergence are validated through numerical simulations. The results suggest that the two-scalar model is more accurate than the one-scalar model in cases with large diffusivity ratios.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Materials Science, Multidisciplinary
Taotao Li, Xiaolong Xie, Jingfeng Xu, Ruifeng Li, Kai Qi, Xiaoqiang Zhang, Hangyu Yue, Yue Zhao, Lei Qiao
Summary: This paper discusses the successful welding of AZ31 Mg alloy to 22MnB5 high-strength steel using pinless friction stir welding (P-FSSW), and optimizing the process conditions through comprehensive analysis of welding parameters. The study provides a detailed examination of the interfacial layer formation between AZ31 Mg alloy and 22MnB5 steel, emphasizing the importance of Al for effective bonding in Mg alloys.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Mechanics
Tao Wang, Haoyue Han, Guangyan Huang, Zhanli Liu, Zhuo Zhuang
Summary: This paper proposes a new phase-field model for explaining the fracture behavior of thick shells under bending loads and demonstrates its effectiveness through numerical examples.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Engineering, Multidisciplinary
Jia-Yu Ye, Roberto Ballarini, Lu-Wen Zhang
Summary: Designing durable polymer-based materials and structures requires understanding the physical processes and failure mechanisms associated with moisture intrusion and loading rate. Although experiments have provided general insight, in-situ characterization and rational prediction of failure in a moisture-mechanical coupling environment remain challenging.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Construction & Building Technology
Gelen Gael Chewe Ngapeya, Daniele Waldmann
CONSTRUCTION AND BUILDING MATERIALS
(2020)
Article
Green & Sustainable Science & Technology
Marielle Ferreira Silva, Laddu Bhagya Jayasinghe, Daniele Waldmann, Florian Hertweck
Article
Green & Sustainable Science & Technology
Laddu Bhagya Jayasinghe, Daniele Waldmann
Article
Construction & Building Technology
Gelen Gael Chewe Ngapeya, Daniele Waldmann
JOURNAL OF BUILDING ENGINEERING
(2020)
Article
Mechanics
Thanh-Tung Nguyen, Daniele Waldmann, Tinh Quoc Bui
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2020)
Review
Green & Sustainable Science & Technology
Arghavan Akbarieh, Laddu Bhagya Jayasinghe, Daniele Waldmann, Felix Norman Teferle
Article
Engineering, Civil
Dolgion Erdenebat, Daniele Waldmann
ENGINEERING STRUCTURES
(2020)
Article
Green & Sustainable Science & Technology
Michael Rakotonjanahary, Frank Scholzen, Daniele Waldmann
Article
Environmental Sciences
Lorenc Bogoviku, Daniele Waldmann
Summary: This study proposes a methodology to assess mineral building stock and predicts the potential amount of waste that may be generated in the future. The research found that Luxembourg's construction stock is continuously growing, and the annual waste production is expected to be sufficient for a viable concrete recycling activity if regulations on waste volume flows are made available.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2021)
Article
Engineering, Mechanical
Hooman Eslami, Laddu Bhagya Jayasinghe, Daniele Waldmann
Summary: This study proposes a constitutive material model for simulating the nonlinear mechanical response of timber under a three-dimensional stress state, implementing the model as a user material subroutine UMAT in ABAQUS. The results show a good agreement between numerical simulations and experimental data, suggesting that the proposed model can be further used in numerical simulations of timber's anisotropic behavior.
ENGINEERING FAILURE ANALYSIS
(2021)
Article
Construction & Building Technology
Vishojit Thapa, Daniele Waldmann
Summary: The study showed that using calcined GWM powder as a partial replacement for Ordinary Portland cement in blended cement pastes and concretes can enhance the long-term properties of the concrete, reducing drying shrinkage and progression of carbonation.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Patrick Pereira Dias, Vanessa Jesuino Kammer, Daniele Waldmann
Summary: This study examines the load-bearing capacity of masonry blocks made from Miscanthus concrete in dry-stacked walls, confirming their suitability for practical use. By optimizing the mixture composition, the ultimate load capacity was improved, and the impact of geometrical imperfections on contact area and applied load was explored.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Patrick Pereira Dias, Laddu Bhagya Jayasinghe, Daniele Waldmann
Summary: This study investigates Gaussian process regression (GPR) to predict the compressive strength of Miscanthus lightweight concrete. The GPR model with rational quadratic kernel shows minimum errors in predicting the compressive strength of MLWC. Additionally, a user-friendly GUI is developed using MATLAB to deploy the GPR model for early-stage design of Miscanthus concrete members.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Anna Tokareva, Sinan Kaassamani, Daniele Waldmann
Summary: Construction and demolition waste can be potentially used as supplementary cementitious materials in blended cement production, which can reduce CO2 emissions by at least 10.7%. Thermal treatment of waste materials at 500 degrees C improves the mechanical properties of mortars, and pozzolanic ceramic inclusions in waste powders do not affect mortar strength at a 20% substitution rate.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Vishojit Bahadur Thapa, Daniele Waldmann
CEMENT & CONCRETE COMPOSITES
(2020)
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)