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1

Three-dimensional analysis of laminated plates with functionally graded layers by two-dimensional numerical model

Pluciński Piotr, Jaśkowiec Jan

Engineering Transactions

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2020

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Vol. 68, iss. 1

21--45

EN

This work presents a three-dimensional (3D) numerical analysis of multi-layered laminated plates in which selected layers may be made of functionally graded material (FGM), in which the Young’s modulus may change along the thickness as a consequence of a continuous and graded mixture of two materials. For the analysis, the method, known as FEM23, is applied, which uses a two-dimensional (2D) mesh, yet enables obtaining full 3D results for the layered structure. In FEM23, the layered structure may be a combination of thin and thick layers made of materials with significantly different properties. This paper presents two examples comparing the results to other numerical or analytical solutions. The examples confirm the correctness and flexibility of FEM23 for laminated plates with functionally graded layers.

2

Elastic modules identification by layered composite beams testing

Diveyev B., Konyk S.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 72, nr 1

14--22

EN

Purpose: The study aims to predict elastic properties of composite laminated plates from the measured mechanical properties. Design/methodology/approach: Elastic constants of laminates and damping properties have been determined by using an identification procedure based on experiment design, and multi-level theoretical approach. Findings: The present paper is the first attempt at proposing a novel adaptive procedure to derive stiffness parameters from forced sandwich plate’s vibration experiments. Research limitations/implications: In the future the extension of the present approach to sandwich plates with different core materials will be performed in order to test various experimental conditions. Practical implications: Structures composed of laminated materials are among the most important structures used in modern engineering and especially in the aerospace industry. Such lightweight and highly reinforced structures are also being increasingly used in civil, mechanical and transportation engineering applications. Originality/value: The main advantage of the present method is that it does not rely on strong assumptions on the model of the plate. The key feature is that the raw models can be applied at different vibration conditions of the plate by a suitable analytical ore approximation method

3

Effects of hygrothermal conditions on cross-ply laminated plates resting on elastic foundations

Zenkour A. M., Allam M. N. M., Radwan A. F.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

144--159

EN

The influence of temperature and moisture on the hygrothermal behavior of laminated composite plates resting on elastic foundations is investigated using a refined plate theory. The material properties of the composite are affected by the variation of temperature and moisture. The present plate theory enables the trial and testing of different through-the-thickness transverse shear-deformation distributions and, among them, strain distributions that do not involve the undesirable implications of the transverse shear correction factors. The governing equations are derived based on the present theory, including hygrothermal effects and elastic foundation parameters. The effects of Winkler and Pasternak foundation parameters, temperature, moisture concentration, transverse shear deformation, plate aspect ratio, side-to-thickness ratio on deflections and stresses are investigated.

4

On Functionally Graded Piezoelectric Actuators for Applications in Structural Vibration Control

Pietrzakowski M.

Machine Dynamics Problems

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2008

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Vol. 32, No. 4

78-94

EN

The aim of the present study is to develop models of active laminated plates containing monolithic piezopolymer sensor layers and a new type of actuator layers made of functionally graded piezoelecrtic material (FGPM). The electromechanical properties of the FGPM actuators can be tailored varying the piezoceramic volume fraction across the thickness during the manufacturing process. Two types of FGPM actuator are under consideration. The first is represented by a multi-layered actuator stacked of distinct piezoelectric fiber composite (PFC) laminae, which differ each other with an amount of piezoceramic (PZT) fibers to change its electromechanical properties quasi continuously according to a power low. In the second case two-phase material being a mixture of piezoceramics and matrix material (e.g. polymer or epoxy resin) is examined. Three distribution functions, which describe the gradient of volume fraction constituents, are considered: exponential, parabolic and sigmoid. The analysis and numerical simulations are focused on the relationship between the material compositional gradient and electromechanical properties and also dynamic responses of the structure. The effective properties of the FGPM, i.e. the Young's modulus and piezoelectric coefficient gradations, are determined. The dynamic analysis concerns steady-state behaviour of rectangular symmetrically laminated plates due to the classical plate theory. The numerical simulations are performed to recognize the influence of the applied pattern of the piezoceramic fraction distribution and its parameters on the gradient of elastic and piezoelectric properties across the FGPM actuators and, as the final result, the active plate structural response presented in terms of amplitude-frequency characteristics. The changes in both the natural frequencies and resonant amplitudes are compared and the influence of the piezoceramic gradation on the control system operational effectiveness is also discussed.

5

Dynamic rigidity and loss factor prediction for composite layered panel

Diveyev B., Smolskyy A., Sukhorolskyy M.

Archives of Materials Science and Engineering

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2008

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Vol. 31, nr 1

45-48

EN

Purpose: The study aims to predict the dynamic rigidity and loss factor properties of composite laminated plates. Design/methodology/approach: Dynamic rigidity and loss factor properties have been determined by using a numerical schemes based on multi-level theoretical approach. Findings: The present paper is the first attempt at proposing a novel adaptive procedure to derive dynamic rigidity and damping parameters for sandwich plate’s vibration. Research limitations/implications: In the future the extension of the present approach to sandwich plates with different core materials will be performed in order to test various sandwich design. Practical implications: Structures composed of laminated materials are among the most important structures used in modern engineering and especially in the aerospace industry. Such lightweight and highly reinforced ructures are also being increasingly used in civil, mechanical and transportation engineering applications. Originality/value: The main advantage of the present method is that it does not rely on strong assumptions on the model of the plate. The key feature is that the raw models can be applied at different vibration conditions of the plate by a suitable analytical or approximation method

6

Analiza płyt laminowanych z zastosowaniem zastępczych modeli jednowarstwowych

Sabik A., Kreja I.

Acta Mechanica et Automatica

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2008

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Vol. 2, no. 1

63-68

PL

W pracy przedstawiono analizę porównawczą wybranych modeli obliczeniowych płyt warstwowych, zgodnych z koncepcją zastępczego modelu jednowarstwowego (Equivalent Single Layer - ESL). Rozważono trzy modele bazujące na teorii ścinania pierwszego rzędu: dwa modele autorskie oraz model paneli laminowanych dostępny w systemie MSC/NASTRAN. Zróżnicowanie modeli wynika z odmiennego podejścia do tzw. korekty ścinania. Przeprowadzono obliczenia dla szeregu przykładów testowych dostępnych w literaturze. Jeśli było to możliwe, dokonano porównań z innymi modelami typu ESL, zwłaszcza bazującymi na teorii ścinania wyższych rzędów. Analizę ograniczono do statyki liniowej.

EN

The aim of the paper is to evaluate the performance of several equivalent single-layer models in the framework of linear static analysis of multilayered plates. The effectiveness of approaches based on the first-order as well as on the higherorder shear deformation theories is discussed. Special attention is paid to various techniques of shear correction, which is required in the case of first-order shear deformation based models. To test the efficiency of several shear correction methods, the authors perform computations with their own programs and commercial package MSC/Nastran.

7

Loss factor prediction for laminated plates

Diveyev B.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 25, nr 1

41-44

EN

Purpose: The study aims to predict the loss factor properties of composite laminated plates. Design/methodology/approach: Elastic constants of laminates and damping properties have been determined by using an identification procedure based on multi-level theoretical approach. Findings: The present paper is the first attempt at proposing a novel adaptive procedure to derive loss factor parameters for sandwich plate's vibration. Research limitations/implications: In the future the extension of the present approach to sandwich plates with different core materials will be performed in order to test various sandwich design. Practical implications: Structures composed of laminated materials are among the most important structures used in modern engineering and especially in the aerospace industry. Such lightweight and highly reinforced structures are also being increasingly used in civil, mechanical and transportation engineering applications. Originality/value: The main advantage of the present method is that it does not rely on strong assumptions on the model of the plate. The key feature is that the raw models can be applied at different vibration conditions of the plate by a suitable analytical or approximation method.

8

Dynamic properties identification for laminated plates

Diveyev B., Stocko Z., Topilnyckyj V.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

227-230

EN

Purpose: The study aims to identify elastic properties of laminated plates from the measured dynamical properties. Design/methodology/approach: Elastic constants of laminates have been determined by using an identification procedure based on experiment design, and multi-level theoretical approach. Findings: The present paper is the first attempt at proposing a novel procedure to derive stiffness parameters from forced sandwich plates. The main advantage of the present method is that it does not rely on strong assumptions on the model of the plate. The key feature is that the raw models can be applied at different vibration conditions of the plate by a suitable analytical ore approximation method. Research limitations/implications: In the future the extension of the present approach to sandwich plates will be performed in order to test various experimental conditions. Practical implications: Structures composed of laminated materials are among the most important structures used in modern engineering and especially in the aerospace industry. Such lightweight and highly reinforced structures are also being increasingly used in civil, mechanical and transportation engineering applications. Originality/value: The main advantage of the present method is that it does not rely on strong assumptions on the model of the plate. The key feature is that the raw models can be applied at different vibration conditions of the plate by a suitable analytical ore approximation method.

9

Composites with Piezoceramic Fibers and Interdigitated Electrodes in Vibration Control

Pietrzakowski M.

Mechanika / Akademia Górniczo-Hutnicza im. St. Staszica

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2003

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T. 22, z. 3

375-380

EN

The study concerns active suppression of structural vibrations of laminated plates. The configuration of the proposed control device is based on the piezoceramic fiber composite layers equipped with the interdigitated electrodes and used as actuators and sensors. This type of hybrid composites with the poling direction along the fibers offers an increase of the predominant unidirectional actuation effect and also the orthotropy of electromechanical properties comparing with the traditional piezoceramic fiber composites. The effective composite properties are obtained due to the uniform field method by combining the material phases properties according to the rules of mixtures. The steady-state behavior of the actively damped laminated plate is analyzed. The governing equations are formulated for a non-zero skew angle between the natural axes of the piezoelectric composite materiał and the plate reference axes. The numerical simulations are focused on the influence of the piezoceramic arrangement on the control potential of the considered system.

10

Transverse Actuation of Laminated Plates via Active Layers with Piezoceramic Fibers

Pietrzakowski M.

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2002

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z. 60 [197]

497-505

EN

In the paper the problem of orthotropic actuation of transverse structural vibrations using the Interdigitated Electrode Piezoelectric Fiber Composites (IDEPFCs) is analysed. The system considered is a thin symmetrically laminated rectangular plate with the embedded active IDEPFC layers or patches glued to the plate surfaces. The uniform fields approach is applied to derive the electromechanical constitutive relations and to model the piezoelectric device effective properties. The governing equation of the plate motion induced by the actuators supplied with an external voltage is formulated and solved for the steady-state case and simply supported boundary conditions. The influence of the piezoceramic material fraction and the active composite architecture including an orientation of the principal material axes on the dynamic response of the system is numerically examined and discussed.