Layered composites have attracted attention for their high specific stiffness, high specific strength, and application specific tailoring of their properties. It is also recognized that layered composites are prone to delamination failure in addition to other failure modes. Consideration of transverse shear on the deformation behavior of the composites is an important aspect in the study of delamination mode failure of such plates. In this paper, we consider the effects of including the transverse shear deformation on the vibration characteristics of layered piezoelectric composites. The formulation is based on the Raleigh-Ritz method using the beam characteristic functions. MATLAB based symbollic math tool box is used in evaluating th eintegrals resulting from the Raleigh Ritz approach. Various commonly occuring boundary conditions are discussed. Results are provided showing the effects of the shear deformation on the dynamics of layered laminated composites. The effects of laminate thickness, fiber orientation, and the plate aspect ratios on the free vibration characteristics of the composite laminates are given to demonstrate the methodology described.
Layered composites have attracted attention for their high specific stiffness, high specific strength, and application specific tailoring of their properties. It is also recognized that layered composites are prone to delamination failure in addition to other failure modes. Consideration of transverse shear on the deformation behavior of the composites is an important aspect in the study of delamination mode failure of such plates. In this paper, we consider the effects of including the transverse shear deformation on the vibration characteristics of layered composites. The formulation is based on the Raleigh-Ritz method using the beam characteristic functions. In addition to including the transverse shear, the formulation is developed for metal-fiber-layered composite plates. This type of laminate construction offers the advantage of both the metallic and fiber properties. Various commonly occuring boundary conditions are discussed. Results are provided showing the effects of the shear deformation on the metal-fiber laminates. The effects of laminate thickness, fiber orientation, and the plate aspect ratios on the free vibration characteristics of the metlal-fiber laminates are given to demonstrate the methodology described.
Inflatable structures are effective in space applications, as they are weight, volume and cost competitive. For certain space applications, higher gains are obtained for the antennas by increasing their size. Higher gains often result in increased data throughput. These and other advantages lead to inflatable structures being considered increasingly for building large space structures. However, large inflatable structures are prone to surface errors arising from environmental factors, among others. In this context, piezoelectric films are used for the active and passive control. In this paper, we discuss numerical approaches exploring piezoelectric film. In order to explore the applications of piezoelectric films, a circular diaphragm is subjected to varying pressures and displacements are measured using laser instrumentation. The effects of applying voltage on the shape of the piezoelectric film subjected to pressurization are studied. The piezoelectric film is modeled as a large displacement/large rotation membrane undergoing small strains. This paper presents experience gained in modeling the piezoelectric film subjected to both thermal and pressure loads. The numerical results are presented in the form of graphs. The response is studied for applied steady-state temperatures for various pressurization levels. Certain thermo-structural instabilities were encountered in the modeling and the paper presents procedures used in circumventing such instabilities for the piezoelectric type of thin inflatable membranes.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.