Influence of porosity on the fundamental natural frequencies of FG sandwich beams

2022 ◽  
Author(s):  
Guermit Mohamed Bilal Chami ◽  
Amar Kahil ◽  
Lazreg Hadji
Keyword(s):  
Natural Frequencies ◽  
Sandwich Beams

scholarly journals The Vibration Response of Composite Sandwich Beam with Delamination

2007 ◽  
Vol 16 (2) ◽  
pp. 096369350701600 ◽  
Author(s):  
Buket Okutan Baba ◽  
Ronald F. Gibson
Keyword(s):  
Finite Element ◽  
Natural Frequencies ◽  
Sandwich Beam ◽  
Laminated Composite ◽  
Sandwich Beams ◽  
Element Analysis ◽  
Composite Sandwich ◽  
Dimensional Finite Element ◽  
Vibration Tests ◽  
Non Destructive

The aim of this study is to report the effect of delamination on the vibration characteristics of composite sandwich beams. The natural frequencies and corresponding vibration modes of a free-free sandwich beam with delamination of various sizes and locations are predicted using a two-dimensional finite element analysis (FEA). The presence of delamination affects the stiffness of the delaminated beam and results in differences on the natural frequencies of the beam. Assessment of the differences light the way for the existence, size and location of the delaminated region and can be used for a non-destructive evaluation of the damage characteristics of the delaminated beams. Vibration tests are conducted on fully bonded sandwich beams with carbon/epoxy laminated composite faces and foam core to verify the finite element results. Agreement between predictions of the model and experimental observations is good.

Free Vibration Analysis of FGM Sandwich Beams Containing Edge Cracks

2012 ◽  
Vol 488-489 ◽  
pp. 230-235 ◽  
Author(s):  
Javad Soltani Rad ◽  
Ali Tivay ◽  
Mojtaba Sadighi
Keyword(s):  
Vibration Analysis ◽  
Natural Frequencies ◽  
Free Vibration Analysis ◽  
Flexural Vibration ◽  
Functionally Graded ◽  
Finite Element Models ◽  
Sandwich Beams ◽  
Crack Configuration ◽  
Different Depths ◽  
Edge Cracks

This paper presents a vibration analysis of sandwich beams with functionally-graded skins containing edge cracks. Finite Element models of FGM sandwich beams are created with different depths and locations of the edge-cracks, and the first four natural frequencies of the beam are obtained for each crack configuration. The integrity of the data is validated for the FGM skins in comparison to a previously published reference. Finally, an inspection is conducted on the data to show the influences of the location and depth of cracks and material properties on the flexural vibration characteristics of cracked FGM sandwich beams.

Dynamic Analysis of Sandwich Beams Filled with ER Elastomers

2011 ◽  
Vol 50-51 ◽  
pp. 843-848 ◽  
Author(s):  
Quan Bai ◽  
Ke Xiang Wei ◽  
Wen Ming Zhang
Keyword(s):  
Finite Element ◽  
Electric Field ◽  
Vibration Control ◽  
Natural Frequencies ◽  
Flexible Structures ◽  
Sandwich Beam ◽  
Element Model ◽  
Sandwich Beams ◽  
Simulation Results ◽  
Er Fluids

Considered electrorheological (ER) elastomers as the visco-elasticity material, a finite element model of a sandwich beam filled with ER elastomers was developed based on Hamilton’s principle and sandwich beam’s theory. Then its dynamic characteristics were analyzed. Simulation results show that natural frequencies of the sandwich beam increase and vibration amplitudes of the beam decrease as the intensity of applied electric field increases. Increased the thickness of the ER elastomers layer, natural frequencies of the beam decrease and loss factors increase. Those indicate that the dynamic characteristic of ER elastomers sandwich beams is similar as that of ER fluids beam, which can be used for vibration control of flexible structures by applied a electric field.

Natural frequencies of vibration of cantilever sandwich beams

1977 ◽  
Vol 7 (6) ◽  
pp. 737-745 ◽  
Author(s):  
N.A. Rubayi ◽  
S. Charoenree
Keyword(s):  
Natural Frequencies ◽  
Sandwich Beams

Dynamic Responses of Functionally Graded Sandwich Beams Resting on Elastic Foundation Under Harmonic Moving Loads

2018 ◽  
Vol 18 (09) ◽  
pp. 1850112 ◽  
Author(s):  
Wachirawit Songsuwan ◽  
Monsak Pimsarn ◽  
Nuttawit Wattanasakulpong
Keyword(s):  
Boundary Conditions ◽  
Elastic Foundation ◽  
Natural Frequencies ◽  
Moving Load ◽  
Beam Theory ◽  
Equation Of Motion ◽  
Functionally Graded ◽  
Dynamic Responses ◽  
Harmonic Load ◽  
Sandwich Beams

This paper investigates the free vibration and dynamic response of functionally graded sandwich beams resting on an elastic foundation under the action of a moving harmonic load. The governing equation of motion of the beam, which includes the effects of shear deformation and rotary inertia based on the Timoshenko beam theory, is derived from Lagrange’s equations. The Ritz and Newmark methods are employed to solve the equation of motion for the free and forced vibration responses of the beam with different boundary conditions. The results are presented in both tabular and graphical forms to show the effects of layer thickness ratios, boundary conditions, length to height ratios, spring constants, etc. on natural frequencies and dynamic deflections of the beam. It was found that increasing the spring constant of the elastic foundation leads to considerable increase in natural frequencies of the beam; while the same is not true for the dynamic deflection. Additionally, very large dynamic deflection occurs for the beam in resonance under the harmonic moving load.

Natural Frequencies of Vibration of Fixed-Fixed Sandwich Beams

1961 ◽  
Vol 28 (3) ◽  
pp. 367-371 ◽  
Author(s):  
M. E. Raville ◽  
En-Shiuh Ueng ◽  
Ming-Min Lei
Keyword(s):  
Infinite Series ◽  
Close Agreement ◽  
Natural Frequencies ◽  
Experimental Results ◽  
Lagrangian Multiplier ◽  
Sandwich Beams ◽  
Different Dimensions ◽  
Lagrangian Multiplier Method ◽  
Theoretical Results

In this paper, the problem of the determination of the natural frequencies of vibration of fixed-fixed sandwich beams is analyzed by an energy approach in which the Lagrangian multiplier method is utilized to satisfy the boundary conditions of the problem. The solution is in the form of a rapidly converging infinite series. Experimental results are given for 21 sandwich beams having different dimensions and physical constants. Corresponding theoretical results, obtained by means of a digital computer, are in close agreement with the experimental results.

scholarly journals A study on dynamic response of functionally graded sandwich beams under different dynamic loadings

2018 ◽  
Vol 192 ◽  
pp. 02011
Author(s):  
Wachirawit Songsuwan ◽  
Monsak Pimsarn ◽  
Nuttawit Wattanasakulpong
Keyword(s):  
Timoshenko Beam ◽  
Natural Frequencies ◽  
Equations Of Motion ◽  
Beam Theory ◽  
Functionally Graded ◽  
Transverse Shear Deformation ◽  
Sandwich Beams ◽  
Governing Equations ◽  
Dynamic Loadings ◽  
Parametric Studies

In this research, free and forced vibration of functionally graded sandwich beams is considered using Timoshenko beam theory which takes into account the significant effects of transverse shear deformation and rotary inertia. The governing equations of motion are formulated from Lagrange's equations and they are solved by using The Ritz and Newmark methods. The results are presented in both tabular and graphical forms to show the effects of layer thickness ratios, boundary conditions, length to height ratios, etc. on natural frequencies and dynamic deflections of the beams. According to the numerical results, all parametric studies considered in this research have significant impact on free and forced behaviour of the beams; for example, the frequency is low and the dynamic deflection is large for the beams which are hinged at both ends.

Sign in / Sign up

Export Citation Format

Share Document