STUDIES RELATING TO THE STRUCTURAL DYNAMIC BEHAVIOR OF LAMINATED PLATES AND SHELLS
In this paper, a number of studies related to structural dynamic behavior of laminated orthotropic plates and shells is reported. The plate or shell structure is composed of an arbitrary number of bonded elastic orthotropic layers, whose principal elastic axes coincide with the coordinate axes. These studies are based on two main approaches to the problem, viz., formulations by shell theory and by linear elasticity theory. First, attention is directed toward a shell theory formulation, where a constitutive relation including transverse shear deformation is given. The relation involves composite correction factors which are determined by consideration of plane waves in a plate with the same layered construction. A method is then presented for the determination of frequencies and modal patterns of plane wave motions in laminated orthotropic plates within the framework of linear elasticity so as to permit evaluation of these composite correction factors. This elasticity solution can also be used to assess the accuracy of the shell theory when applied to plates. Next, a method is given for the study of vibrations and waves in laminated orthotropic plates and cylinders using elasticity equations. Lastly, a finite element formulation for shells of revolution based on the current shell theory is presented. Conical frustra are employed for the modeling of the shell of revolution. The displacement field adopted requires, in addition to nodes at the ends, a mid-node in the element. Along with the determination of frequencies and mode shapes is a calculation of the percentage distribution of strain energies due to extensional, flexural and transverse shear deformations and this information serves to identify the nature of a given vibratory motion. Comparisons of the present results with known solutions indicate the veracity of the current model.
- Research Sponsored by the Office of Naval Research, Structural Mechanics Division.
University of California, Los AngelesSchool of Architecture and Urban Planning
Los Angeles, CA United States 90024
- Dong, S B
- Publication Date: 1972-5
- Features: Appendices; References;
- Pagination: 144 p.
- TRT Terms: Composite materials; Orthotropic plates; Shells (Structural forms); Structural analysis
- Old TRIS Terms: Orthotropic plate theory; Shell theory
- Subject Areas: Marine Transportation; Materials;
- Accession Number: 00035633
- Record Type: Publication
- Source Agency: Ship Structure Committee
- Report/Paper Numbers: NR 064-519
- Contract Numbers: N00014-71-C-0056
- Files: TRIS
- Created Date: Oct 13 1972 12:00AM