Loading...
Search for:
laminated-composite-beam
0.007 seconds
Vibration Behavior of Laminated Composite Beam Incorporated with MR (Magnetorheological) Fluid under Random Excitation
, Ph.D. Dissertation Sharif University of Technology ; Behzad, Mehdi (Supervisor) ; Zabihollah, Abolghassem (Co-Supervisor)
Abstract
Laminated composite beams are being widely used in engineering applications, including aerospace and automobile where the structures are highly subjected to non-deterministic random loadings, requiring a reliable technique to ensure the stability of structure during operation. A Novel N-layer model of layerwise theory (LWT) for laminated composite beams incorporated with magnetorheological fluid (MR-laminated beams) is developed. In addition, a finite element model of tapered laminated composite beams incorporated with magnetorheological fluid (MR-tapered beam) based on layerwise theory is developed. The dynamic response of the present model for uniform and tapered beams have been compared...
Dynamic Modeling and Analysis of Delaminated Isotropic and Multi- Layered Composite Beam under the Action of Moving Force/Oscillatory Mass
, Ph.D. Dissertation Sharif University of Technology ; Kargarnovin, Mohammad Hossein (Supervisor) ; Ahmadian, Mohammad Taghi (Co-Advisor)
Abstract
In this thesis, a laminated composite beam with single delamination under the action of moving force/oscillatory mass has been modeled and analyzed. The beam has been divided into four sub-beams and based on Bernoulli-Euler and also shear deformation theories and by applying the Hamilton’s principle, equations of motion along with boundary conditions and continuity and compatibility conditions are obtained. Primarily, based on the constrained mode model the delaminated layers have been analyzed then by implementing the Lagrange multipliers method, the nature of dynamic contact is incorporated. In the analysis of delaminated beam based on the constrained mode, by applying the mode summation...
A new approach in finite element modeling of generally laminated composite beams
, Article 2006 ASME International Mechanical Engineering Congress and Exposition, IMECE2006, Chicago, IL, 5 November 2006 through 10 November 2006 ; 2006 ; 01608835 (ISSN); 0791837904 (ISBN); 9780791837900 (ISBN) ; Jafari Talookolaei, R. A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2006
Abstract
In this paper, a new finite element model for a generally laminated composite beam (LCB) is presented. Natural frequencies of a generally LCB are derived by developing the stiffness and mass matrices considering the effects of axial force, shear and torsional deformations and rotary inertia. This model includes coupling of bending and torsional modes of deformations which is usually present in LCBs due to ply orientation. The model is designed in such away that it can be used for single and double stepped crosssection. Comparing numerical results for simple cases with analytical solutions and literature indicate high accurate and quick response of the model. Copyright © 2006 by ASME
An analytical approach for the free vibration analysis of generally laminated composite beams with shear effect and rotary inertia
, Article International Journal of Mechanical Sciences ; Volume 65, Issue 1 , December , 2012 , Pages 97-104 ; 00207403 (ISSN) ; Abedi, M ; Kargarnovin, M. H ; Ahmadian, M. T ; Sharif University of Technology
2012
Abstract
In this paper, the free vibration analysis of generally laminated composite beam (LCB) based on Timoshenko beam theory are presented using the method of Lagrange multipliers where in the free vibration problem is posed as a constrained variational problem. The effect of material couplings (bending-tension, bending-twist, and tension-twist couplings) with the effects of shear deformation, rotary inertia and Poisson's effect are taken into account. Analytical expression for the natural frequencies and mode shapes are presented. The calculated natural frequencies are verified against some available results in the literature and very good agreement is observed. Furthermore, the effects of some...
Dynamics of a generally layered composite beam with single delamination based on the shear deformation theory
, Article Science and Engineering of Composite Materials ; Volume 22, Issue 1 , 2015 , Pages 57-70 ; 0334181X (ISSN) ; Abedi, M ; Kargarnovin, M. H ; Ahmadian, M. T ; Sharif University of Technology
Walter de Gruyter GmbH
2015
Abstract
The free vibration analysis of generally laminated composite beam (LCB) with a delamination is presented using the finite element method (FEM). The effect of material couplings (bending-tension, bending-twist, and tension-twist couplings) with the effects of shear deformation, rotary inertia, and Poisson's effect are taken into account. To verify the validity and the accuracy of this study, the numerical solutions are presented and compared with the results from available references and very good agreement observed. Furthermore, the effects of some parameters such as slenderness ratio, the rotary inertia, the shear deformation, material anisotropy, ply configuration, and delamination...
Effects of nanoparticles on the improvement of the dynamic response of nonuniform-thickness laminated composite beams
, Article Journal of Mechanical Science and Technology ; Volume 30, Issue 1 , 2016 , Pages 121-125 ; 1738494X (ISSN) ; Momeni, S ; Selk Ghafari, A ; Sharif University of Technology
Korean Society of Mechanical Engineers
2016
Abstract
The dynamic behavior of nonuniform-thickness laminated composite beams, such as helicopter blades, wind turbine blades, and robot arms, is of high importance in the design and fabrication of such elements. Changing the thickness of laminated structures is a significant challenge during fabrication because different tapering configurations may significantly alter the stiffness of the structures and thus the dynamic response of the structures. In this study, the effect of adding nanoparticles to resin on the stiffness and dynamic behavior of nonuniform-thickness laminated composite beam elements was investigated. A set of experiments were conducted to examine the natural frequencies and...
Modeling and Vibration Analysis of Laminated Composite Beam with Magneto-Rheological Fluid Segments
, Ph.D. Dissertation Sharif University of Technology ; Behzad, Mehdi (Supervisor) ; Zabihollah, Abolghasem (Supervisor) ; Shamloo, Amir (Co-Advisor)
Abstract
Magnetorheological (MR) materials show variations in their rheological properties when subjected to varying magnetic fields. They have quick time response, in the order of milliseconds, and thus are potentially applicable to structures and devices when a tunable system response is required. When integrated with a structural system, they can produce higher variations in the dynamic response of the structure. In this thesis, vibration behavior of laminated-composite beam with MR Fluid is investigated.In most studies, shear strain across the thickness of MR layer has been considered as a constant value which does not precisely describe the actual shear strain field. Shear modulus of MR layer in...
Numerical and Experimental Analysis of Composite and Honeycomb Sandwich Panels Fatigue Behavior
, M.Sc. Thesis Sharif University of Technology ; Sayyadi, Hassan (Supervisor)
Abstract
The use of sandwich panels has become very common in recent engineering designs when the weight of the part or structure is important and we are looking to lose weight while maintaining strength. The mechanical properties of this type of structures, including yield stress, fatigue behavior and estimation of their life, failure modes, natural frequencies and resonance phenomena, etc. are affected by various factors, including geometric and environmental factors. Fatigue is one of the most common failures in these structures. Composite materials have complex structures. In these materials, due to the viscoelastic properties, the fatigue behavior changes with changing stress, stress frequency,...
A finite element model for tapered laminated beams incorporated with magnetorheological fluid using a layerwise model under random excitations
, Article Mechanics of Advanced Materials and Structures ; Apr , 2018 , Pages 1-8 ; 15376494 (ISSN) ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Laminated composite beams with variable thickness are being widely used in many engineering applications. To enhance the dynamic behavior of structures subject to random loading, tapered laminated beams incorporated with magnetorheological (MR) fluids (MR-tapered beam) are proposed. A finite element model has been developed for random vibration analysis of MR-tapered beam based on layerwise displacement theory. The effects of thickness ratios of tapered beam, magnetic fields, statistical properties, correlation and autocorrelation on dynamic behaviors of structures have been investigated. The proposed structural element significantly enhances the dynamic response of MR-tapered beam under...
Vibration characteristics of laminated composite beams with magnetorheological layer using layerwise theory
, Article Mechanics of Advanced Materials and Structures ; Volume 25, Issue 3 , 2018 , Pages 202-211 ; 15376494 (ISSN) ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Vibration characteristics of laminated composite beams with magnetorheological (MR) layer are investigated using layerwise theory. In most studies, shear strain across the thickness of MR layer has been considered as a constant value, which does not precisely describe the shear strain. In this study, layerwise theory is employed to develop a finite element formulation to investigate MR-laminated beams. Experimental tests under different magnetic fields are carried out to verify the numerical results. Layerwise numerical results are compared with the experimental results and other theories. An empirical expression for complex shear modulus is presented. The effects of MR layer thickness on...
A finite element model for tapered laminated beams incorporated with magnetorheological fluid using a layerwise model under random excitations
, Article Mechanics of Advanced Materials and Structures ; Volume 27, Issue 1 , 2020 , Pages 12-19 ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
Laminated composite beams with variable thickness are being widely used in many engineering applications. To enhance the dynamic behavior of structures subject to random loading, tapered laminated beams incorporated with magnetorheological (MR) fluids (MR-tapered beam) are proposed. A finite element model has been developed for random vibration analysis of MR-tapered beam based on layerwise displacement theory. The effects of thickness ratios of tapered beam, magnetic fields, statistical properties, correlation and autocorrelation on dynamic behaviors of structures have been investigated. The proposed structural element significantly enhances the dynamic response of MR-tapered beam under...
Large amplitudes free vibrations and post-buckling analysis of unsymmetrically laminated composite beams on nonlinear elastic foundation
, Article Applied Mathematical Modelling ; Volume 35, Issue 1 , 2011 , Pages 130-138 ; 0307904X (ISSN) ; Jafari Talookolaei, R. A ; Salarieh, H ; Sharif University of Technology
Abstract
The purpose of this paper is to present efficient and accurate analytical expressions for large amplitude free vibration and post-buckling analysis of unsymmetrically laminated composite beams on elastic foundation. Geometric nonlinearity is considered using Von Karman's strain-displacement relations. Besides, the elastic foundation has cubic nonlinearity with shearing layer. The nonlinear governing equation is solved by employing the variational iteration method (VIM). This study shows that the third-order approximation of the VIM leads to highly accurate solutions which are valid for a wide range of vibration amplitudes. The effects of different parameters on the ratio of nonlinear to...
Dynamic response of a delaminated composite beam with general lay-ups based on the first-order shear deformation theory
, Article Composites Part B: Engineering ; Volume 55 , 2013 , Pages 65-78 ; 13598368 (ISSN) ; Kargarnovin, M. H ; Ahmadian, M. T ; Sharif University of Technology
2013
Abstract
The dynamic response analysis of a delaminated composite beam with a general lay-up traversed under an arbitrary moving/non-moving force is presented. By employing the energy method and introducing a new finite element, the global mass and stiffness matrices for a Laminated Composite Beam (LCB) of Timoshenko type are derived in which the material couplings (bending-tension, bending-twist, and tension-twist couplings) with the Poisson's effect are considered. In deriving the governing equation the non-penetration condition is imposed by employing the method of Lagrange multipliers. Out of a self-developed finite element program, the natural frequencies and time response of such LCB are...
Semi-analytical solution for the free vibration analysis of generally laminated composite Timoshenko beams with single delamination
, Article Composites Part B: Engineering ; Volume 45, Issue 1 , 2013 , Pages 587-600 ; 13598368 (ISSN) ; Ahmadian, M. T ; Jafari Talookolaei, R. A ; Abedi, M ; Sharif University of Technology
2013
Abstract
A rather new semi-analytical method towards investigating the free vibration analysis of generally laminated composite beam (LCB) with a delamination is presented. For the first time the combined effects of material couplings (bending-tension, bending-twist, and tension-twist couplings) with the effects of shear deformation, rotary inertia and Poisson's effect are taken into account. The semi-analytical solution for the natural frequencies and mode shapes are presented by incorporating the constraint conditions using the method of Lagrange multipliers. To verify the validity and the accuracy of the obtained results, they were compared with the results from other available references. Very...
Analysis of large amplitude free vibrations of unsymmetrically laminated composite beams on a nonlinear elastic foundation
, Article Acta Mechanica ; Volume 219, Issue 1-2 , January , 2011 , Pages 65-75 ; 00015970 (ISSN) ; Salarieh, H ; Kargarnovin, M. H ; Sharif University of Technology
2011
Abstract
The large amplitude free vibration of an unsymmetrically laminated composite beam (LCB) on a nonlinear elastic foundation subjected to axial load has been studied. The equation of motion for the axial and transverse deformations of a geometrically nonlinear LCB is derived. Using the Ritz method, the governing equation is reduced to a time-dependent Duffing equation with quadratic and cubic nonlinearities. The homotopy analysis method (HAM) is used to obtain exact expressions for the dynamic response of the LCB. This study shows that the third-order approximation of the HAM leads to highly accurate solutions that are valid for a wide range of vibration amplitudes. The effects of different...
Large amplitude thermo-mechanical vibration analysis of asymmetrically laminated composite beams
, Article Key Engineering Materials, 22 March 2011 through 24 March 2011, Kuala Lumpur ; Volume 471-472 , 2011 , Pages 745-750 ; 10139826 (ISSN) ; 9783037850596 (ISBN) ; Alavijeh, H. S ; Pasharavesh, A ; Aghdam, M. M ; Sharif University of Technology
2011
Abstract
In this paper, simple analytical expression is presented for large amplitude thermomechanical free vibration analysis of asymmetrically laminated composite beams. Euler-Bernoulli assumptions together with Von Karman's strain-displacement relation are employed to derive the nonlinear governing partial differential equation (PDE) of motion. He's variational method is employed to obtain a simple and efficient approximate closed form solution of the nonlinear governing equation. Comparison between results of the present work and those available in literature shows the accuracy of presented technique. Some new results for the nonlinear natural frequencies of the laminated beams such as the effect...
Dynamic analysis of generally laminated composite beam with a delamination based on a higher-order shear deformable theory
, Article Journal of Composite Materials ; Volume 49, Issue 2 , 2015 , Pages 141-162 ; 00219983 (ISSN) ; Abedi, M ; Kargarnovin, M. H ; Ahmadian, M. T ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
In this study, the dynamic response of the laminated composite beam with arbitrary lay-ups has been investigated within the framework of the third-order shear deformation theory using the finite element method. A new three-nodded finite element compliant with the theory is introduced next. To deal with the dynamic contact between the delaminated segments, unilateral contact constraints are employed in conjunction with Lagrange multiplier method. Furthermore, the Poisson's effect is incorporated in the formulation of the beam constitutive equation. Also, the higher-order inertia effects and material couplings (flexure-tensile, flexure-twist and tensile-twist couplings) are considered in the...
Vibration behavior of laminated composite beams integrated with magnetorheological fluid layer
, Article Journal of Mechanics ; 2016 , Pages 1-9 ; 17277191 (ISSN) ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Cambridge University Press
Abstract
Vibration behavior of adaptive laminated composite beams integrated with magnetorheological (MR) fluid layer has been investigated using layerwise displacement theory. In most of the existing studies on the adaptive laminated beams with MR fluids, shear strain across the thickness of magnetorheological (MR) layer has been assumed a constant value, resulting in a constant shear stress in MR layer. However, due to the high shear deformation pattern inside MR layer, this assumption is not adequate to accurately describe the shear strain and stress in MR fluid layer. In this work a modified layerwise theory is employed to develop a Finite Element Model (FEM) formulation to simulate the laminated...
Vibration behavior of laminated composite beams integrated with magnetorheological fluid layer
, Article Journal of Mechanics ; Volume 33, Issue 4 , 2017 , Pages 417-425 ; 17277191 (ISSN) ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Cambridge University Press
2017
Abstract
Vibration behavior of adaptive laminated composite beams integrated with magnetorheological (MR) fluid layer has been investigated using layerwise displacement theory. In most of the existing studies on the adaptive laminated beams with MR fluids, shear strain across the thickness of magnetorheological (MR) layer has been assumed a constant value, resulting in a constant shear stress in MR layer. However, due to the high shear deformation pattern inside MR layer, this assumption is not adequate to accurately describe the shear strain and stress in MR fluid layer. In this work a modified layerwise theory is employed to develop a Finite Element Model (FEM) formulation to simulate the laminated...
Experimental works on dynamic behavior of laminated composite beam incorporated with magneto-rheological fluid under random excitation
, Article ACM International Conference Proceeding Series, 8 February 2017 through 12 February 2017 ; Volume Part F128050 , 2017 , Pages 156-161 ; 9781450352802 (ISBN) ; Zabihollah, A ; Behzad, M ; Sharif University of Technology
Association for Computing Machinery
2017
Abstract
Laminated composite structures are widely being used in modern industries particularly robot arms, aerospace and wind turbine blades where the structures mainly exposed to harsh random vibration and in turn, leads to unpredicted failure. Adding Magneto-rheological (MR) fluids in such structures may significantly improve their dynamic response. In the present work, the vibration response of laminated composite beams filled with MR fluids (MR laminated beam) under random loading has been investigated using experimental as well as simulation approaches. Finite Element Model (FEM) has been utilized to simulate the vibration response under random loading. An in-house set-up has been designed to...