Article
Mechanics
Sergey A. Lurie, Alexander L. Kalamkarov, Yury O. Solyaev, Alexander V. Volkov
Summary: This paper presents a simplified version of the strain gradient elasticity theory and derives two variants with different forms of boundary conditions. The correctness of the theory formulations is discussed, and analytical solutions for various problems are obtained and compared for the two variants.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2021)
Article
Engineering, Multidisciplinary
Junchao Wu, Xinyu Wu, Yaobing Zhao, Dongdong Wang
Summary: A rotation-free Hellinger-Reissner meshfree thin plate formulation is proposed to naturally accommodate the essential boundary conditions in a variationally consistent way. In this approach, the bending moment is expressed as the second order smoothed gradients which inherently embed the integration constraint and fulfill the variational consistency condition. The enforcement of essential boundary conditions has a similar form as that of the Nitsche's method, but with replaced derivatives and without artificial parameters.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Engineering, Multidisciplinary
S. Ali Faghidian, Krzysztof Kamil Zur, J. N. Reddy
Summary: The proposed higher-order unified gradient elasticity theory effectively characterizes the nanoscopic response of advanced nano-materials, as demonstrated by its application to study the torsional behavior of elastic nano-bars and determine the shear modulus of nano-sized bars in closed-form analytical formula. Additionally, a practical approach to calibrate characteristic lengths is introduced.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2022)
Article
Mechanics
Dezhong Tong, Andrew Choi, Jungseock Joo, Andy Borum, Mohammad Khalid Jawed
Summary: In this study, the snap buckling behavior of overhand knots in elastic rods is investigated using a combination of DDG-based simulations and tabletop experiments. The phenomenon of inversion, where the loop of the knot appears to dramatically move from one side to the other, is attributed to the coupling of elastic energy between the braid and the loop. Numerical simulations and simplified models both successfully capture the inversion process and are in agreement with experimental results.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2023)
Article
Mechanics
Oliver S. Gibson, Chris Knotek, Lawrence Virgin, Earl Dowell
Summary: This study presents the results of an experimental investigation into the buckling behavior of a vertically cantilevered plate subjected to corner twisting forces. The findings reveal a peculiar instability in which the slender panel exhibits nonlinear out-of-plane corner deflections when laterally loaded. This study is unique in that it examines the buckling of cantilevered plates and specifically focuses on buckling under twisting loads. The experimental results are compared with finite element analysis simulations, showing good agreement in terms of the change in buckling load with plate aspect ratio.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2023)
Article
Mechanics
A. R. El-Dhaba, A. F. Ghaleb, Mohamed I. M. Hilal
Summary: This work investigates the Flamant-Boussinesq problem for a half-space made of a homogeneous and isotropic dielectric material. Both the dynamical flexoelectric effect and the dynamical flexocoupling between displacement and polarization are considered. The first strain gradient theory of elasticity is used and an analytical harmonic wave solution is obtained. The results are analyzed graphically and the damping phenomenon is discussed.
Article
Mechanics
Hossein Darban, Raimondo Luciano, Andrea Caporale, Michal Basista
Summary: This paper formulates a novel buckling model for nanobeams resting on the Pasternak elastic foundation based on the local-nonlocal stress-driven gradient elasticity theory. The model accurately predicts the buckling loads and mode shapes of the nanobeams, and captures both stiffening and softening behaviors at small scales.
COMPOSITE STRUCTURES
(2022)
Article
Mechanics
S. Ceballes, A. Abdelkefi
Summary: In this research, the general nonlocal elasticity theory is applied to study the buckling and dynamic responses of a nanobeam with varying boundary conditions. The selection of an appropriate guess function is found to be necessary for the approximate solution. The findings of this study are important for simplifying analysis procedures and understanding the fundamental relationships in nanobeam-based systems.
EUROPEAN JOURNAL OF MECHANICS A-SOLIDS
(2022)
Article
Engineering, Multidisciplinary
Alireza Daneshyar, Payam Sotoudeh, Mohsen Ghaemian
Summary: The classical theory of elasticity fails to reproduce reasonable responses when the size effects are pronounced, while the gradient-dependent theory of elasticity, which incorporates higher-order spatial and temporal derivatives, addresses this shortcoming. In this study, a numerical solution method based on the scaled boundary finite element method and the shooting technique is proposed, and its capability in reproducing accurate responses is demonstrated through verification and comparison.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Subrat Kumar Jena, S. Chakraverty, Mohammad Malikan
Summary: This study focuses on the buckling behavior of strain gradient nonlocal beams on Winkler elastic foundations. By combining the first-order strain gradient model with the Euler-Bernoulli beam theory using Hamilton's principle, the study employs three numerical methods (HWM, HOHWM, and DQM) to analyze buckling characteristics and study the impact of various parameters on critical buckling loads. A comprehensive presentation of the numerical methods and a comparative study on their convergence demonstrate the effectiveness and applicability of the methods in analyzing the buckling behavior. The findings of this investigation are properly validated with previous works.
ENGINEERING WITH COMPUTERS
(2021)
Article
Chemistry, Multidisciplinary
Sheng Qian, Yifeng Ni, Yi Gong, Fan Yang, Qi Tong
Summary: This study finds that using a gradient nanograined structure can enhance the damping capacity of metals. The GB orientations in the gradient grains can facilitate GB sliding, thus increasing the damping capacity. This structure can also maintain the level of material strength and achieve a synergy of strength, ductility, and damping.
Review
Computer Science, Interdisciplinary Applications
Alexander Mueller, Manfred Bischoff
Summary: We propose a objective, singularity-free, path independent, numerically robust and efficient geometrically non-linear Reissner-Mindlin shell finite element formulation. The formulation is especially suitable for higher order ansatz spaces and utilizes geometric finite elements for interpolation on non-linear manifolds. The article compares three different interpolation schemes for the shell director and investigates different methods for updating the nodal directors. The path independence, efficiency and objectivity of the formulation are verified through numerical examples.
ARCHIVES OF COMPUTATIONAL METHODS IN ENGINEERING
(2022)
Article
Thermodynamics
Victor A. Eremeyev, Antonio Cazzani, Francesco dell'Isola
Summary: Nonlinear dilatational strain gradient elasticity theory examines a specific class of continuum materials where deformation energy is related to the gradients of placement and the determinant of the gradient of placement in an objective manner. This theory is a particular case within the complete Toupin-Mindlin nonlinear strain gradient elasticity, showcasing unique second gradient effects arising from the non-uniform dilatation state of deformable bodies. Dilatational second gradient continua are closely linked to other scalar microstructure models and can be seen as a result of solidification of strain gradient fluids. Through a variational approach, equilibrium conditions for dilatational second gradient continua are derived and analyzed, highlighting their ability to support contact forces on edges and surface curves. Additionally, possibilities for externally applicable double forces and curve forces are explored, with a focus on small deformations and practical applications such as axial deformations and dilatational wave propagation in elastic tubes.
CONTINUUM MECHANICS AND THERMODYNAMICS
(2021)
Article
Mechanics
Federico Oyedeji Falope, Matteo Pelliciari, Luca Lanzoni, Angelo Marcello Tarantino
Summary: This paper investigates the equilibrium and stability of a von Mises truss made of rubber material subjected to a vertical load using theoretical, numerical, and experimental methods. The study includes the development of analytical models, finite element simulations, and the identification of constitutive parameters through a genetic algorithm. Experimental observations show good agreement with theoretical and numerical results, revealing insights on snap-through and Eulerian buckling. The accuracy of predicting critical loads is validated through experiments, highlighting the importance of nonlinear formulations for accurate predictions.
INTERNATIONAL JOURNAL OF NON-LINEAR MECHANICS
(2021)
Article
Physics, Multidisciplinary
Sihan Chen, Tomer Markovich, Fred C. MacKintosh
Summary: Networks of semiflexible or stiff polymers deform non-homogeneously when sheared, and the effects of this nonaffine deformation are stronger than for flexible polymers. Current understanding of nonaffinity in these systems is limited to simulations or specific 2D models. A new effective medium theory is presented here, which is applicable to both 2D and 3D systems, in both thermal and athermal regimes, and demonstrates good agreement with computational and experimental results for linear elasticity. This framework can also be extended to study nonlinear elasticity and network dynamics.
PHYSICAL REVIEW LETTERS
(2023)
Article
Construction & Building Technology
Jerome Claverie, Fabrice Bernard, Joao Manuel Marques Cordeiro, Siham Kamali-Bernard
CEMENT AND CONCRETE RESEARCH
(2020)
Article
Construction & Building Technology
Jerome Claverie, Siham Kamali-Bernard, Joao Manuel Marques Cordeiro, Fabrice Bernard
Summary: In this study, the two most common polymorphs, M1 and M3, in industrial alite were characterized at the molecular scale, with assessments of mechanical properties and specific heat using different methods. The calculated homogenized elastic moduli and specific heat were found to agree well with experimental measurements. A comparative analysis showed isotropic and anisotropic spatial distribution for M1 and M3, respectively, with M1 also having a more isotropic compressive strength.
CEMENT AND CONCRETE RESEARCH
(2021)
Article
Materials Science, Composites
Jia Fu, Jiaxuan Huang, Fabrice Bernard
Summary: The anisotropy of Bi2Te3 and Sb2Te3 crystals were studied, elastic properties of composite Bi2Te3/Sb2Te3 thin films were modeled, and Debye temperatures, thermal conductivity, and ZT values were analyzed to enhance the thermoelectric performance. The research showed a promising multiscale modeling scheme from single crystal films to multilayer composite thin films for high ZT value improvement by reducing band gap and thermal conductivity.
COMPOSITES COMMUNICATIONS
(2021)
Review
Construction & Building Technology
Jerome Claverie, Qianqian Wang, Siham Kamali-Bernard, Fabrice Bernard
Summary: This article reviews the increasing use of atomistic simulations over the last decade to study cementitious materials properties. It focuses on investigations based on density functional theory, molecular dynamics, and related methods to assess the reactivity and hydration of Portland cement clinker phases at the nanoscale. The limitations of these methods are discussed, and alternative approaches and challenges are introduced.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Engineering, Civil
Khaled Benali, Baghdad Krour, Mohamed Atif Benatta, Khetir Hafid, Mohamed Bachir Bouiadjra, Ismail Mechab, Fabrice Bernard
Summary: Strengthening concrete beams using prestressed or not prestressed composite plates is a widely used technique in civil engineering to improve infrastructure durability, particularly against seismic forces. This research proposes an analytical model based on the high-order theory and the laminate theory to determine the dynamic characteristics of prestressed composite plates used for reinforcing concrete beams. The inclusion of prestressing tension, which was not considered in earlier studies, is the main innovation of this research. Parametric studies varying prestressing tension and fiber orientations were conducted to find the optimal use of the composite plates. Finite element models were also used to compare the behavior of the composite plate under different boundary conditions. The research demonstrates that prestressing effectively strengthens the composite plates, increasing natural frequencies and reducing deflection, making it a strong choice for reinforcing prestressed concrete beams.
ENGINEERING STRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Lazreg Hadji, Fabrice Bernardi, Nafissa Zouatnia
Summary: This paper analyzes the bending and free vibration of porous functionally graded (PFG) beams resting on elastic foundations. The material features of the PFG beam are assumed to vary continuously through the thickness. The foundation medium is linear, homogeneous, and isotropic, modeled using the Winkler-Pasternak law. The hyperbolic shear deformation theory is applied for kinematic relations, and the equations of motion are obtained using Hamilton's principle. An analytical solution is presented assuming simple support. Comparisons with the open literature are made to verify the validity of the formulation. The effects of elastic foundations, porosity volume percentage, and span-to-depth ratio are discussed in detail.
FDMP-FLUID DYNAMICS & MATERIALS PROCESSING
(2023)
Article
Construction & Building Technology
Riadh Bennai, Redhwane Ait Atmane, Fabrice Bernard, Mokhtar Nebab, Noureddine Mahmoudi, Hassen Ait Atmane, Salem Mohammed Aldosari, Abdelouahed Tounsi
Summary: This paper investigates the buckling and free vibration of imperfect, functionally graded beams with micro porosities using a higher order shear strain theory. It presents a novel porosity distribution affecting the functionally graded volume fraction and derives the equations of motion using Hamilton's principle. The numerical results are compared with other research to verify accuracy and precision.
STEEL AND COMPOSITE STRUCTURES
(2022)
Article
Materials Science, Multidisciplinary
Prince Momar Gueye, Siham Kamali-Bernard, Dame Keinde, Fabrice Bernard, Vincent Sambou
Summary: This study investigates the potential reuse of fly ash and bottom ash in the construction field. By analyzing their granular size, density, chemical composition, and microstructure, it is found that fly ash is similar to cement, while bottom ash is similar to fine sand. Adding fly ash to mortar improves its mechanical strength, while adding bottom ash significantly decreases it.
FDMP-FLUID DYNAMICS & MATERIALS PROCESSING
(2022)
Article
Engineering, Multidisciplinary
Sow Libasse, Bernard Fabrice, Kamali-Bernard Siham
Summary: The paper presents a hierarchical multi-scale modelling approach for investigating the mechanical behavior of cement-bound gravels using NHWI bottom ashes. The study determined elastic moduli of NHWI particles and mechanical parameters characterizing the gravel treated with 3% cement, showing feasibility of reusing industrial by-products. The modelling approach was validated through comparisons with experimental literature results.
INTERNATIONAL JOURNAL OF ENGINEERING RESEARCH IN AFRICA
(2021)
Article
Materials Science, Multidisciplinary
Lazreg Hadji, Fabrice Bernard, Abdelkader Safa, Abdelouahed Tounsi
Summary: In this paper, a hyperbolic shear deformation plate theory is presented for functionally graded plates with consideration of porosities that may occur during fabrication. Numerical examples show that the distribution form of porosity significantly influences the mechanical behavior of functionally graded plates.
ADVANCES IN MATERIALS RESEARCH-AN INTERNATIONAL JOURNAL
(2021)
Proceedings Paper
Construction & Building Technology
R. Hin, K. Cheng, V Han, F. Bernard, C. Seang, V Keryvin, J-C Sangleboeuf
4TH INTERNATIONAL CONFERENCE ON CONSTRUCTION AND BUILDING ENGINEERING & 12TH REGIONAL CONFERENCE IN CIVIL ENGINEERING (ICONBUILD & RCCE 2019)
(2020)
Article
Engineering, Civil
Noureddine Elmeichea, Hichem Abbadb, Ismail Mechabc, Fabrice Bernard
STRUCTURAL ENGINEERING AND MECHANICS
(2020)
Article
Engineering, Civil
Mokhtar Nebab, Soumia Benguediab, Hassen Ait Atmane, Fabrice Bernard
GEOMECHANICS AND ENGINEERING
(2020)
Article
Engineering, Civil
Setti Elmascri, Aicha Bessaim, Ouahiba Taleb, Mohammed Sid Ahmed Houari, Sekkal Mohamed, Fabrice Bernard, Abdelouahed Tounsi
STRUCTURAL ENGINEERING AND MECHANICS
(2020)
Article
Materials Science, Multidisciplinary
Lazreg Hadji, Fabrice Bernard
ADVANCES IN MATERIALS RESEARCH-AN INTERNATIONAL JOURNAL
(2020)
