Article
Engineering, Geological
Alessandro Tengattini, Giang D. Nguyen, Gioacchino Viggiani, Itai Einav
Summary: This paper presents an experimental and analytical/numerical study of the mechanics of cemented granular materials. The study combines in situ X-ray tomography and finite element simulations to gain insight into the multiscale processes that drive the mechanical response of these materials. The paper explores the effects of boundary conditions on grain-scale processes and material properties, and validates a micromechanically inspired constitutive model at different scales.
Article
Construction & Building Technology
Jialong He, Hui Jiang, Yuande Zhou, Feng Jin, Chuhan Zhang
Summary: Artificial cementation can improve the modulus and strength properties of granular materials and is important for analyzing their performance. This study investigates the behavior of dual-particle composites cemented by self-compacting mortar and proposes a unit model for numerical simulation of cemented granular materials.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Engineering, Geological
Soheil Mohajerani, Gang Wang, Yuntian Zhao, Feng Jin
Summary: A novel peridynamics model is developed in this paper to investigate the mechanical behaviors of CGMs with different volume fractions of the cementitious phase. The model considers key mechanical phenomena including inter-particle frictional contact, distribution of cement bonds, and cement clogs between particles. The simulation results show significant variations in the mechanical parameters of CGMs with changes in the cement volume fraction.
Article
Materials Science, Multidisciplinary
Daoguang He, Shi-Bing Chen, Y. C. Lin, Han Xie, Chengbo Li
Summary: The high-temperature tensile features of a 7046-aluminum alloy were studied by conducting hot tensile experiments under different forming parameters. The influences of tensile forming parameters on the flow behaviors and fracture characteristics were analyzed. The improved Hensel-Spittel-Carofalo (HSC) model and long short-term memory (LSTM) model were proposed to reproduce the hot tensile characteristics. The results showed that the formation of dimples was aggravated at high strain rate, but the coalescence of dimples increased with the ascending of tensile temperature, leading to better elongation to fracture. The developed LSTM model and improved HSC model exhibited preferred reconstructing capability for the high-temperature tensile behaviors of the researched aluminum alloy, as verified by the analysis.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Bingyao Yan, Yanqiu Zhang, Shuyong Jiang, Junbo Yu, Dong Sun, Ming Tang
Summary: The mechanical properties and fracture mechanisms of martensitic NiTi shape memory alloy were studied through thermomechanical processing, leading to significant changes in microstructure and differences in plasticity and fracture strength of the alloy. The decrease in plasticity in the annealed alloy is mainly attributed to the reduction of reorientation+detwinning zone and plastic zone, as well as the difference in crack-path configuration resulting in a larger proportion of fracture mode I in the annealed alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Mechanics
Rossella Laudani, Martin Ostoja-Starzewski
Summary: The violation of the entropy inequality in macroscopic granular media undergoing collisional dynamics is found to be a result of the fluctuation theorem of nonequilibrium thermodynamics. Through molecular dynamics simulations, it is determined that the occurrence of negative entropy increments is influenced by the Eulerian velocity gradient and the Young modulus of the disks.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2021)
Article
Mechanics
Zhuangzhuang Wang, Xiaofei Cao, Qinglei Zeng, Jizhen Wang, Ying Li
Summary: This study investigated the dynamic fracture behaviors of three different cellular materials under numerical simulations. The results showed that the fracture toughness of the triangular honeycomb increases with loading velocity, while the fracture toughness of the other two structures remains relatively constant. The microstructure of the material has a greater influence on the rate-dependence of fracture toughness than the constituent material.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Multidisciplinary Sciences
Xiaohui Cheng, Shize Xiao, Alex Sixie Cao, Meiying Hou
Summary: This study investigates transitional regimes in granular shear flows, proposing a unified model to describe transitions between different flow states based on triaxial shear flow tests. The importance of granular viscosity under low pressure is highlighted in the transition between quasi-static and moderate Isotach type flow states.
SCIENTIFIC REPORTS
(2021)
Article
Computer Science, Interdisciplinary Applications
Yizhao Gao, Qingshuo Hao, Peng Yu, Yuzhen Yu, He Lv
Summary: This study proposes a new constitutive model for granular soils, considering two types of volume variations and the state dependency of material density. The model includes compression and unloading curves considering grain crushing, and can accurately describe the stress-dilatancy relation under different experimental conditions.
COMPUTERS AND GEOTECHNICS
(2023)
Article
Engineering, Geological
Trung-Kien Nguyen, Jacques Desrues, Thanh-Trung Vo, Gael Combe
Summary: In this paper, a multi-scale model that combines the finite element method (FEM) and the discrete element method (DEM) is presented to study the behavior of cemented granular materials (CGM). The model considers inter- and intra-granular cracking and examines the behavior of the material at both the macroscopic and microscopic scales. The results show that the occurrence of shear bands leads to significant changes in the material's microscopic characteristics.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Engineering, Mechanical
Charalampos Konstantinou, Emilio Martinez-Paneda, Giovanna Biscontin, Norman A. Fleck
Summary: In this study, microbiologically-induced calcium carbonate precipitation (MICP) was used to manufacture laboratory-scale specimens for fracture toughness measurement. The dependencies of mode I and mixed-mode fracture toughness on cementation, as well as their correlations with strength, permeability, and porosity, were investigated. A micromechanical model was developed to predict the relationship between mode I fracture toughness and the degree of cementation. The role of crack tip T-stress in determining kink angle and toughness under mixed mode loading was also determined.
EXTREME MECHANICS LETTERS
(2023)
Article
Engineering, Mechanical
Vinh T. Le, Ha H. Bui, Giang D. Nguyen, Jayantha Kodikara, Didier Bodin, James Grenfell
Summary: This paper presents a constitutive model that considers the strain discontinuity across fracture planes and describes the fatigue behavior in cemented materials. The model effectively captures the significant influence of stress amplitudes on the fatigue lives of materials, making it an essential tool for predicting and mitigating fatigue-induced damage.
INTERNATIONAL JOURNAL OF FATIGUE
(2023)
Article
Construction & Building Technology
Wei Qin, Feng Jin, Siyuan Yang, Duruo Huang
Summary: This study utilizes X-ray microtomography to investigate the microstructure of 3D cemented granular materials (CGMs) formed by cement grouting and explores the effect of flow-ability of self-compacting cement (SCC) on their microstructure. The results reveal that the cross-sectional area distribution of intergranular bonding follows a log-normal distribution. Furthermore, both the average cross-sectional area and the average number of intergranular bonds increase linearly with the yield stress of SCC. The influence of cementing ratio on the anisotropy degree of various cemented structures is also illustrated, providing a viable means to understand the reinforcement effect of cementation.
JOURNAL OF ADVANCED CONCRETE TECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Nima Noii, Amirreza Khodadadian, Fadi Aldakheel
Summary: This work proposes a probabilistic approach to phase-field brittle and ductile fracture, considering random material and geometric properties. The macroscopic failure mechanics assumes homogeneity and determinism in materials properties and spatial quantities, while the lower scale with strong fluctuation in properties is approximated with uncertainty. The proposed model employs representative volume elements with random distribution of inclusions and voids to model the uncertainty. Monte Carlo Finite Element Method is used to solve the stochastic PDE-based model and approximate the expected value and variance of the solution field. The model is effective for predicting failure mechanisms in brittle/ductile fracture.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Review
Engineering, Geological
Xiuhan Yang, Sai K. Vanapalli
Summary: This paper summarizes studies on the strain-softening behavior of unsaturated soils published in the literature over the past three decades. The studies are categorized into mechanical characteristics and micromechanisms, prediction models for shear strength, and numerical methods for modeling strain-softening behavior. The influence of soil-water characteristic curve and time effects on strain-softening behavior are also discussed. The comprehensive details provided in this paper are valuable for the analysis and design of geostructures in unsaturated soils undergoing large shear deformation.
INTERNATIONAL JOURNAL OF GEOMECHANICS
(2023)
Article
Engineering, Geological
Alessandro Tengattini, Giang D. Nguyen, Gioacchino Viggiani, Itai Einav
Summary: This paper presents an experimental and analytical/numerical study of the mechanics of cemented granular materials. The study combines in situ X-ray tomography and finite element simulations to gain insight into the multiscale processes that drive the mechanical response of these materials. The paper explores the effects of boundary conditions on grain-scale processes and material properties, and validates a micromechanically inspired constitutive model at different scales.
Article
Engineering, Geological
Alessandro Tengattini, Edward Ando, Itai Einav, Gioacchino Viggiani
Summary: This paper presents an experimental analysis of cement damage and fragment rearrangement in cemented granular materials, using in-situ X-ray tomography and novel image processing approaches. The study reveals the spatial correlation between cement damage and strain rate, as well as their effect on the isotropy of the bonds.
Article
Mechanics
David Riley, Itai Einav, Francois Guillard
Summary: Porous media, such as dry snow, cellular foams, or cereals, can undergo abrupt and recurring stress drops when subjected to mechanical loading. The initiation mechanism of these stress drops is still debated, but it is widely accepted that they coincide with the destruction of the material's meso-scale structure. However, a general predictive method to accommodate these stress drops at the constitutive level for porous media is still lacking.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2023)
Article
Materials Science, Ceramics
M. H. Moreira, S. Dal Pont, A. Tengattini, V. C. Pandolfelli
Summary: Refractory castables are commonly used materials for high-temperature processes due to their excellent performance and easy installation. However, their operational condition is hindered by the slow drying stage required. This study investigates the effect of heating rate on moisture clog and finds that higher heating rates lead to faster and longer-lasting water accumulation, aligning with previous studies and explaining the preference for slower heating rates in industrial operations. The study highlights the potential of neutron imaging in maximizing the efficiency of the drying process of refractory castables.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Engineering, Chemical
Helen Lewis, Gary Couples, Alessandro Tengattini, Jim Buckman, Erika Tudisco, Maddi Etxegarai, Gioacchino Viggiani, Stephen A. Hall
Summary: Neutron imaging is used to directly observe water-air and deuterated water-normal water exchanges in flow experiments on microporous limestone. The study reveals significant water speed and flow direction variability at the deci-micron scale, as well as complex patterns of water saturation. The findings suggest that capillarity-driven and pressure-driven water movement occur concurrently and compete with each other, with their dominance changing as water saturations evolve.
TRANSPORT IN POROUS MEDIA
(2023)
Article
Environmental Sciences
Itai Einav, Mario Liu
Summary: Water retention in soil exhibits diverse phenomena, including suction-saturation hysteresis, non-unique air entrapment at zero suction, and negative suction under partial saturations. The constancy of suction after a long rest can be broken by minor mechanical or hydraulic agitations, leading to metastable states. The non-equilibrium Landau's hydrodynamic theory and Onsager's reciprocity principles are used to recover the complete suction-saturation relationships and describe rate independence conditions while accommodating rate-dependency.
WATER RESOURCES RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Robert Bradbury, Nikolay Kardjilov, Georg F. Dewald, Alessandro Tengattini, Lukas Helfen, Wolfgang G. Zeier, Ingo Manke
Summary: The elucidation of lithium ion transport pathways through a solid electrolyte separator is important for the development of all-solid-state batteries. Neutron imaging was performed on an all-solid-state lithium-sulfur battery using an increased Li-6 content in the anode. This allowed for differentiation between the mobile lithium ions diffusing through the cell and those initially located in the solid electrolyte, and demonstrated the lithium ion diffusion through the cell and the distribution of trapped lithium ions in charged and discharged states.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Water Resources
Max P. Cooper, Rishabh P. Sharma, Silvana Magni, Tomasz P. Blach, Andrzej P. Radlinski, Katarzyna Drabik, Alessandro Tengattini, Piotr Szymczak
Summary: The dissolution of porous media leads to the formation of wormhole-like channels within rocks, which provide efficient flow paths. Understanding the formation of these wormholes is important for controlling contaminant migration or preventing CO2 leakage. In this study, we used time-resolved X-ray tomography to capture the dynamics of wormhole propagation and found a complex relationship between wormhole advancement and rock permeability. We also identified highly cemented regions that act as barriers to flow. These results demonstrate the potential of using time-lapse captured wormhole dynamics to probe the internal structure of rocks.
ADVANCES IN WATER RESOURCES
(2023)
Article
Electrochemistry
H. Altaf, T. Milicic, T. Vidakovic-Koch, E. Tsotsas, Alessandro Tengattini, N. Kardjilov, T. Arlt, I. Manke, N. Vorhauer-Huget
Summary: In this study, neutron imaging was used to visualize and study invasion phenomena in fibrous porous transport layers (PTLs) of titanium felt under different flow conditions of gas and liquid phase. The invasion process was characterized by counter-current flow of water and air with joint imbibition and drainage processes. Neutron radiography and tomography were used to visualize the dynamics and study the static gas-liquid distributions. The results showed that the invasion occurred in repeated imbibition/drainage cycles, with frequencies depending on the flow conditions and the PTL structure.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Construction & Building Technology
Andreas Alhede, Jelke Dijkstra, Samanta Robuschi, Alessandro Tengattini, Karin Lundgren
Summary: The behavior of corrosion products in corrosion-induced cracking is not well understood. This study experimentally investigated the corrosion and cracking processes in 3D using nondestructive neutron and X-ray computed tomography. A method to evaluate the average volumetric strain of the compressed corrosion layer was proposed and displacements in the concrete matrix were measured. Strain localization revealed cracks not directly visible in the images. Multimodal tomography demonstrated to be an effective method for investigating steel corrosion in reinforced concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Food Science & Technology
Ilija Vego, Richard T. Benders, Alessandro Tengattini, Frank J. Vergeldt, Joshua A. Dijksman, John P. M. Duynhoven
Summary: The mechanical behavior of hygroscopic granular materials is greatly influenced by water, which affects the packing response of individual particles and can lead to loss of product functionality. This study aims to link water uptake to microstructural changes in assemblies of couscous through experimental analysis. The results show that water uptake and particle swelling are linearly correlated, indicating the importance of understanding the fundamental connection between particle and packing behavior in hygroscopic granular materials.
FOOD STRUCTURE-NETHERLANDS
(2023)
Article
Engineering, Multidisciplinary
Axel Henningsson, Adrian G. Wills, Stephen A. Hall, Johannes Hendriks, Jonathan P. Wright, Thomas B. Schon, Henning F. Poulsen
Summary: This study investigates the problem of estimating crystal elastic strain tensor from strain tensor probability distribution, and provides analytical parametrizations and maximum-likelihood estimations in the case of multivariate Gaussian strain tensor distribution. The proposed algorithm is demonstrated to be useful in single crystal monochromatic X-ray scattering through numerical simulations.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Yanzheng Wang, Qian Wu, Yiran Tian, Guoliang Huang
Summary: This paper proposes the microstructure design of an odd plate and investigates the directional wave energy amplification and the presence of interface waves in odd plates through theoretical and numerical analysis. The research findings contribute to the understanding of elastic behavior in 2D non-Hermitian systems.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
F. Greco, D. Codony, H. Mohammadi, S. Fernandez-Mendez, I. Arias
Summary: This study overcomes the difficulty of harnessing the flexoelectric effect by designing multiscale metamaterials. Through topology optimization calculations, we obtain optimal structures for various apparent piezoelectric properties and find that low-area-fraction lattices are the preferred choice. The results show competitive estimations of apparent piezoelectricity compared to reference materials such as quartz and PZT ceramics.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Xiaoxuan Zhang, Tryaksh Gupta, Zhenlin Wang, Amalie Trewartha, Abraham Anapolsky, Krishna Garikipati
Summary: This study presents a computational framework for coupled electro-chemo-(nonlinear) mechanics at the particle scale in solid-state batteries, including interfacial fracture, degradation in charge transfer, and stress-dependent kinetics. The discontinuous finite element method allows for arbitrary particle shapes and geometries.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Chengguan Zhang, Xavier Balandraud, Yongjun He
Summary: The coexistence of both austenite and martensite is a common characteristic in Shape Memory Alloys (SMAs). The multiple-domain microstructures, consisting of austenite, martensite twins, and individual martensite variants, evolve collectively during the phase transformation, affecting the material's macroscopic response. This paper presents an experimentally observed interface consisting of five domains in a Ni-Mn-Ga single-crystal, and analyzes the effects of thermal loading path and material initial state on the domain pattern formation.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Shaobao Liu, Haiqian Yang, Guang-Kui Xu, Jingbo Wu, Ru Tao, Meng Wang, Rongyan He, Yulong Han, Guy M. Genin, Tian Jian Lu, Feng Xu
Summary: The balance between stress and adhesion plays a crucial role in governing the behaviors of adherent cells, such as cell migration. In certain microenvironments, such as tumor, variations in hydrostatic pressure can significantly impact cell volume and adhesion, which in turn affects cell behavior.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Xun Xiong, Qinglei Zeng, Yonghuan Wang, Ying Li
Summary: In this work, the authors investigate the possibility of enhancing the resistance to crack growth in brittle materials through microstructure design. They establish a computational framework to simulate crack propagation and characterize fracture energy. The effects of different types of voids on toughening mechanisms are explored, and the critical conditions for embrittlement-toughening transition are identified. The study also discusses the difference between void toughening in brittle and ductile materials, and extends the toughening strategy to nacre-like materials.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Huan Wang, Yong-Quan Liu, Jiu-Tao Hang, Guang-Kui Xu, Xi-Qiao Feng
Summary: This study establishes a cytoarchitectural model to accurately capture the buckling and postbuckling behaviors of epithelia under fast compression. The stress evolution of epithelia is divided into three stages: loading, phase transition, and stress recovery. The postbuckling process is governed by the active tension generated by the actomyosin network. The study also proposes a minimal model that predicts the flattening time and stress recovery extent as functions of applied strain or strain rate, in agreement with simulations and experiments.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Lei Liu, Hao Liu, Yuming He, Dabiao Liu
Summary: This study investigates the mechanics and topologically complex morphologies of twisted rubber filaments using a combination of experiment and finite strain theory. A finite strain theory for hyperelastic filaments under combined tension, bending, and torsion has been established, and an experimental and theoretical morphological phase diagram has been constructed. The results accurately determine the configuration and critical points of phase transitions, and the theoretical predictions agree closely with the measurements.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Abhishek Painuly, Kunnath Ranjith, Avinash Gupta
Summary: This paper analyzes the interfacial waves caused by frictional slipping and studies their dispersion relation and wave modes. By studying the slip waves in a geophysical model, the surface wave dispersion phenomenon is explored, and an alternative explanation is proposed.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Houlin Xu, Joshua Vievering, Hoang T. Nguyen, Yupeng Zhang, Jia-Liang Le, Zdenek P. Bazant
Summary: Motivated by the extraordinary strength of nacre, this study investigated the probabilistic distribution of fishnet strength using Monte Carlo simulations and found that previous analytical solutions are not applicable for fishnets with a large number of links. By approximating large-scale fishnets as a continuum with cracks or holes, the study revealed that the strength distribution follows the Weibull distribution. This new model has significance for optimizing the strength-weight ratio in printed material structures.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Souhayl Sadik, Arash Yavari
Summary: This paper revisits the mathematical foundations of nonlinear viscoelasticity and studies the geometry of viscoelastic deformations. It discusses the decomposition of the deformation gradient into elastic and viscous distortions and concludes that the viscous distortion can only be a two-point tensor. The governing equations of nonlinear viscoelasticity are derived and the constitutive and kinetic equations for various types of viscoelastic solids are discussed.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Wen Cheng, Hongkuan Zhang, Yu Wei, Kun Wang, Gengkai Hu
Summary: In this study, we propose a phenomenon similar to Thouless pumping for a continuous in-plane elastic system, enabling topological transport of elastic waves through spatial modulation of material elasticity. By incorporating specific lattice microstructures, termed pentamode materials, precise and robust control over elastic wave propagation is achieved.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
Article
Materials Science, Multidisciplinary
Linda Werneck, Mertcan Han, Erdost Yildiz, Marc-Andre Keip, Metin Sitti, Michael Ortiz
Summary: We have developed a simple model that describes the ionic current through neuronal membranes by considering the membrane potential and extracellular ion concentration. The model combines a simplified Poisson-Nernst-Planck model of ion transport through individual ion channels with channel activation functions calibrated from experimental data. The calibrated model accounts for the transport of calcium, sodium, potassium, and chloride and shows remarkable agreement with experimentally measured current-voltage curves for human neural cells.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2024)
