Article
Mechanics
Marianna Puccia, Antonino Spada, Giuseppe Giambanco
Summary: This paper presents a numerical strategy for simulating localized failure in structures made of quasi-brittle materials using finite element method. The strategy includes a thin interphase layer and a crack tracking algorithm, which can accurately capture the degradation and deformation behavior. The proposed method is validated with benchmark examples and shows good mesh-size and mesh-bias independence.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Mechanics
Manh Van Pham, Minh Ngoc Nguyen, Tinh Quoc Bui
Summary: This paper proposes an improved local continuum damage model for analyzing quasi-brittle fracture. The model incorporates fracture energy and element characteristic length to mitigate the mesh-size dependency issue. The enhanced bi-energy norm and equivalent strain are used to simulate mixed-mode fracture behavior. Numerical examples demonstrate the accuracy and effectiveness of the developed local damage approach in modeling quasi-brittle fracture, especially in predicting crack paths.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Chenjie Yu
Summary: In this paper, a vector-based damage-driven computational homogenization with localized gradient enhanced boundary conditions is proposed to tackle the challenges in brittle and quasi-brittle materials. The homogenization method uses crack band theory to upscale damage and introduces damage in the principal direction. The localized displacement gradients are updated iteratively to consider crack propagation and surrounding elements, and computational robustness is guaranteed with incremental sequentially linear analysis.
COMPUTERS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Sana Zafar, Ahmadreza Hedayat, Omid Moradian
Summary: This study conducted laboratory-scale experiments and data analysis on rock specimens to understand the evolution of tensile and shear cracking under different stress levels. By using acoustic emission and digital image correlation techniques, we were able to track the changes in the source mechanisms of the cracks and identify the correlation between the cracking mechanisms at different stages of the cracks.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
George Z. Voyiadjis, Yaneng Zhou, Peter Kattan
Summary: An anisotropic elasto-plastic-damage model is developed for quasi-brittle materials within the thermodynamics framework, including the introduction of plastic strain energy and damage criteria to consider the material's behavior under different loadings.
MECHANICS OF MATERIALS
(2022)
Article
Engineering, Geological
Susheng Wang, Lunyang Zhao, Wanlu Zhang
Summary: This study proposes an enhanced constitutive model for quasi-brittle rocks by incorporating the evolution of localized damage. The model accurately predicts the strength and post-peak mechanical behaviors of rocks.
Article
Engineering, Multidisciplinary
Lu Ren, Lun-Yang Zhao, Fu -Jun Niu
Summary: In cold regions, the combined action of freeze-thaw cycling and loading has a significant impact on the stability of engineering structures. This study proposes a physically-based elastoplastic damage model for quasi-brittle geomaterials under freeze-thaw cycles and loading within the framework of irreversible thermodynamics. The model describes the entire deformation and failure process of the material and introduces a new nonlinear evolution law of freeze-thaw damage based on micro-mechanics.
APPLIED MATHEMATICAL MODELLING
(2022)
Article
Engineering, Multidisciplinary
Alok Negi, Sachin Kumar
Summary: This article presents a continuous-discontinuous approach that introduces a discontinuous character to the quasi-brittle fracture process modeled in a continuous setting. The discontinuous framework is developed by enhancing the problem fields in the critically damaged regions using discontinuous interpolations and the eXtended Finite Element Method (XFEM). The proposed approach incorporates improved spatial nonlocal diffusive behavior and uses level sets to track the discontinuity within the finite element mesh. The continuous-discontinuous approach combines the advantages of the gradient damage method and XFEM, while exhibiting improved convergence using low-order finite elements during numerical simulations.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Robert Keqi Luo
Summary: The effective shear strain Yt criterion was developed to evaluate fatigue damage in rubber components. The relation between the Yt criterion and the existing effective tensile strain et criterion was revealed. Six damage criteria, including maximum principal strain, stress, and strain energy density, were compared using cylindrical dumbbell samples under different fatigue cases. The proposed criteria were successfully validated and found to be useful for predicting crack orientation and for antivibration product design.
MECHANICS OF MATERIALS
(2023)
Article
Engineering, Geological
Erick Rogenes, Marcio Muniz de Farias, Leandro Lima Rasmussen
Summary: This paper presents a numerical model for representing the fracture process in hard rocks, validated through calibration with laboratory test results for Creighton granite. A sensitivity study led to the proposal of a calibration methodology to facilitate future use of the CVBM.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Sebastien Michel, Andras A. Sipos
Summary: This paper investigates the order of appearance and the position of meridional cracks in brittle domes using a dimension-reduced model. The results show that a simple, deterministic approach based on the Griffith theory of fracture predicts quasi-equidistant emerging cracks. The variation of the in-plane elastic support and the bending rigidity of the ring significantly affect the order of emergence. The relationship between the mechanical model and geometric properties of the emerging pattern is studied numerically.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Computer Science, Interdisciplinary Applications
Darui Ren, Baoguo Liu, Jinglai Sun, Lei Weng, Zhaofei Chu
Summary: An interacting wing-crack based mesoscale model is developed to describe the elastoplastic damage behaviors of brittle rocks under compressive loading. The model can reasonably simulate triaxial test results and characterize the macroscopic mechanical behavior and damage evolution of rocks.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Mechanics
Rong Chen, Xiao-Kai Hu, Ming-Liang Zhu, Fu-Zhen Xuan
Summary: In this study, the near-tip strain was characterized and statistically analyzed to develop a strain-based criterion for evaluating crack-tip plasticity under both tensile and fatigue loadings. The near-tip strain of 304 stainless steel followed a Lognormal distribution, while that of 25Cr steel followed a Gauss distribution and evolved to a Logistic-Gauss-Lognormal distribution with fatigue crack growth and plasticity increase. A relative strain accumulation parameter was proposed, which represented the branch or stable growth mode, and fatigue crack growth occurred when the relative strain accumulation exceeded 1.3. The cracking speed parameter was established and indicated that different cracking behaviors at the macro-scale behaved similarly at the atomic scale. Microstructural damage analysis revealed that fatigue crack growth in 25Cr steel was governed by breakdown of lathy martensite and formation of fine grains, while cracking in 304 stainless steel was accompanied by austenite-to-martensite transformation occurring at a near-tip strain of approximately 13%.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Materials Science, Multidisciplinary
Taufiq Abdullah, Kedar Kirane
Summary: This paper investigates the mesh objectivity in dynamic fracture analyses using strain rate dependent damage evolution as the localization limiter. It is found that the rate dependent damage model only yields mesh objective predictions at higher loading rates, while results are not mesh objective at lower loading rates. The regularization effect at higher rates is due to an intrinsic length-scale induced by the rate dependent damage law.
MECHANICS OF MATERIALS
(2023)
Article
Engineering, Geological
Rongchao Xu, Shengzhe Zhang, Zhen Li, Xinming Yan
Summary: The study examines the influence of strain rate on the crack stress threshold in different types of rocks and reveals the mechanical mechanism of hard rocks exhibiting different strength and deformation characteristics at various strain rates. The findings show that the strain rate has a significantly different effect on the damage stress level of different rock types. The strain characteristics of granite and sandstone are mainly influenced by the unstable crack propagation stage, with higher strain rates leading to more pronounced volumetric dilatation. The research results have important implications for engineering excavation.
Article
Engineering, Civil
Pere Roca, Andrew Liew, Philippe Block, David Lopez Lopez, Tomas Mendez Echenagucia, Tom Van Mele
Summary: The Extended Limit Analysis of Reinforced Masonry (ELARM) is a user-friendly method for the design and analysis of reinforced tile vaults. This paper presents a three-dimensional approach to ELARM and describes its application in the design and evaluation of reinforced masonry, reinforced concrete, and concrete-masonry composite shells.
Review
Computer Science, Interdisciplinary Applications
M. Cervera, G. B. Barbat, M. Chiumenti, J. -Y. Wu
Summary: This work presents a critical comparison between three different numerical approaches for computational modelling of quasi-brittle structural failure. The study analyzes the relative performance of XFEM, mixed strain/displacement FE, and phase-field models, assessing load capacity, force-displacement curves, crack paths, collapse mechanisms, cost-efficiency, and other key issues. Through an extensive evaluation against selected numerical benchmark problems, the advantages and difficulties of each approach in practical engineering applications are discussed.
ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING
(2022)
Article
Architecture
Belen Jimenez, Luca Pela
Summary: This study investigates the use of simple Lumped Plasticity Models (LPM) and macro-mechanical Finite Element (FE) approaches to evaluate the seismic response of heritage buildings composed of timber frames and masonry walls. The calibration of these engineering models is derived from a wide set of nonlinear static analyses reproducing benchmark experiments. The study also applies the models to assess the seismic response of two existing timber-masonry hybrid buildings in Valparaiso, Chile.
INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGE
(2023)
Article
Materials Science, Multidisciplinary
Narges Dialami, Ivan Rivet, Miguel Cervera, Michele Chiumenti
Summary: This study develops a novel approach to predict the mechanical properties of fused filament fabricated parts by characterizing them according to different printing patterns, and the results are accurately predicted.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2023)
Article
Architecture
Francesca Marafini, Sara Dimovska, Savvas Saloustros, Cossima Cornado, Pere Roca
Summary: This paper presents the historical development of vertical extensions in unreinforced masonry buildings in the Eixample district of Barcelona and their impact on seismic behavior. The study found that despite the low to moderate seismic hazard of Barcelona, the existing masonry buildings in Eixample pose significant seismic risk due to their average height and slender walls. Vertical extensions were a common solution to meet the increasing population demand, but they add structural irregularities that negatively affect seismic performance.
INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGE
(2023)
Article
Architecture
M. Petracca, G. Camata, E. Spacone, L. Pela
Summary: The aim of this work is to propose a simple and effective constitutive plastic-damage model for the microstructural components of masonry. Plasticity is added for a better representation of the cyclic response of masonry using a simplified implementation. To reduce the numerical issues related to strain-softening and improve solution stability, an IM-PLEX integration algorithm is adopted.
INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGE
(2023)
Article
Engineering, Multidisciplinary
Nirvan Makoond, Luca Pela, Climent Molins
Summary: Widely used simplified analytical methods are not suitable for estimating the tensile force in tie-rods with significant discontinuities or irregularities. To address this challenge, a robust hybrid methodology using a data-driven approach and finite element method is proposed for historical tie-rods. This methodology has been applied to a real case study involving two historical ties.
STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL
(2023)
Article
Engineering, Civil
Chiara Ferrero, Chiara Calderini, Pere Roca
Summary: It is found that rigid no-tension models cannot accurately predict the behavior of dry-joint masonry arches and overestimate the ultimate displacement capacity in experimental tests. By analyzing a small-scale segmental dry-joint masonry arch test, a finite element micro-modelling approach is adopted, and it is discovered that the discrepancies between the predictions from the rigid no-tension model and experimental outcomes are due to the imperfections and deformability of the joints in the physical model. A modeling approach that considers joint deformability is proposed and successfully validated.
ENGINEERING STRUCTURES
(2023)
Editorial Material
Architecture
Paulo B. Lourenco, Pere Roca, Luca Pela
INTERNATIONAL JOURNAL OF ARCHITECTURAL HERITAGE
(2023)
Article
Construction & Building Technology
Albert Cabane, Luca Pela, Pere Roca
Summary: This study focuses on evaluating the effect of confinement on the compressive strength of solid fired clay units. The experiment includes two types of clay bricks and examines different specimen sizes and various surface treatments. The results reveal the factors that influence confinement and suggest the use of oiled PTFE leaves as a promising method for obtaining strength regardless of specimen shape.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Manufacturing
Xufei Lu, Michele Chiumenti, Miguel Cervera, Mehdi Slimani, Iban Gonzalez
Summary: This study investigates the challenges of residual stresses, warpage, and recoater crashes in selective laser melting (SLM) of thin-walled structures. It develops a numerical model to simulate the SLM process and enhances it with recoater effects. The study finds that higher laser energy input results in larger residual stresses and warpage, leading to recoater crashes. Potential solutions to mitigate warpage and recoater crashes are assessed using the validated model.
JOURNAL OF MANUFACTURING AND MATERIALS PROCESSING
(2023)
Article
Construction & Building Technology
Jinggao Zhu, Xiaodan Ren, Miguel Cervera
Summary: Due to the formwork-free construction, 3D concrete printing has great potential in the construction industry. However, this method may result in non-verified geometric precision and uncontrolled printing deviations. To address this issue, a process-dependent stochastic method is proposed, and a stochastic analysis procedure is developed and verified using 3D-printed concrete cylinder tests. The study provides insights into the influence of printing deviations and guidance for the design of the 3D printing process.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Albert Cabane, Luca Pela, Pere Roca
Summary: This study evaluates the effect of specimen's slenderness and stacking on the experimental measurement of the compressive strength of solid fired clay units. The experimental results show that the stacking process has an influence on the compressive strength, while the slenderness of the specimens has a more evident and regular impact on the compressive strength in handmade brick specimens.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Civil
David Lopez Lopez, Ernest Bernat-Maso, Savvas Saloustros, Lluis Gil, Pere Roca
Summary: Using tile vaults as stay-in-place formwork for concrete shells can reduce construction costs and material waste, while providing flexibility in design. The combination of masonry and reinforced concrete in a composite structure requires experimental validation and new structural analysis models.
ENGINEERING STRUCTURES
(2023)
Article
Engineering, Manufacturing
Xufei Lu, Chao Chen, Guohao Zhang, Michele Chiumenti, Miguel Cervera, Haoliang Yin, Liang Ma, Xin Lin
Summary: Laser powder bed fusion (LPBF) additive manufacturing (AM) generates residual stresses, which can be reduced through annealing heat treatment (HT). This study investigates the effect of different HT conditions on the residual stresses and warpage of LPBF-fabricated components through experimentation and numerical simulation, and establishes a roadmap for selecting optimal annealing parameters.
ADDITIVE MANUFACTURING
(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)
