Material damping: An introductory review of mathematic measures and experimental technique

In this study, free vibration analysis of conical and cylindrical shells and annular plates made of composite laminated and functionally graded materials (FGMs) is investigated. Carbon nanotubes reinforced (CNTR) composite case is also taken consideration for FGM. The equations of motion for conical shell are obtained via Hamilton's principle using the transverse shear deformation theory. To obtain the eigenvalue problem of the system, the method of discrete singular convolution is employed. Material properties are graded in the thickness direction according to a volume fraction power law and four-parameter power law indexes for FGM cases. Five types of distributions of CNTR material are also considered. To verify the accuracy of this method, comparisons of the present results are made with results available in the open literature. Free vibrations of cylindrical shells and annular plates with FGM are treated as special cases. Results are also presented for carbon nanotubes reinforced (CNTR) composite cylindrical shells and annular plates. It is found that the convergence and accuracy of the present DSC method is very good for vibration problem of shells with functionally graded materials (FMG) and CNTR functionally graded materials.

Free vibration of carbon nanotubes reinforced (CNTR) and functionally graded shells and plates based on FSDT via discrete singular convolution method

Introduction T purpose of this Survey is to review and bring together in an orderly fashion some of the principal contributions to the field of structural mechanics of structures containing composite materials. The topics of micromechanics and fracture, while quite important, are not considered in this Survey. Emphasis is given to the macromechanical structural analysis of various structural elements, including response under conditions of stable static loading, buckling, and dynamics. The Survey unfolds in the following sequence: Straight and Curved Laminated Bars, Laminated Plates, Laminated Shells, Sandwich Structures, Applications to Practical Structural Systems, and Future Trends. The authors hope that this contribution will be a useful reference tool for researchers and engineers already involved in structural aspects of advanced composites, as well as for those who are just entering the field. No Survey can do full justice to such a wide field as compositematerial structural mechanics. The references cited give only a glimpse of the extensive literature in this field. The authors apologize for not citing a number of important contributions in the field.

Composite Material Mechanics: Structural Mechanics

Free vibration of orthotropic conical shells

A 3-D approach to piezoelectric material characterization, based on the assumption that the coordinate axes are pure mode propagation directions, is described. In this case the general equations simplify and an analytical solution can be achieved. For two geometrical shapes (rectangular and cylindrical), stress and strain tensor components and the electrical impedance of the sample are obtained. These 3-D equations show that the wave velocities and permittivity are intrinsic parameters of the medium and do not depend on either the sample geometry or the mode that is considered. This was not true for the 1-D models where the wave velocities and permittivity are different for each of the modes or geometries. >

D.M. Egle

Papers

Free vibrations of orthotropic sandwich conical shells with various boundary conditions

Optimal design of a non-linear dynamic absorber

An experimental investigation of the free vibration of thin cylindrical shells with discrete longitudinal stiffening

A method for selection of significant terms in the assumed solution in a Rayleigh-Ritz analysis

The forced vibrational response of a rectangular parallelepiped with rigid-lubricated boundaries