Scholarly
    Communications Project


Document Type:Master's Thesis
Name:Burak UZMAN
Email address:uzman@optim.esm.vt.edu
URN:1998/00049
Title:Thermal Analysis and Response of Grid-Stiffened Composite Panels
Degree:Master of Science
Department:Engineering Science and Mechanics
Committee Chair: Prof. Zafer Gurdal
Chair's email:gurdal@gurdal.esm.vt.edu
Committee Members:Prof. Michael Hyer
Prof. Eric Johnson
Keywords:Grid, Stiffened, Buckling, Composite Panels
Date of defense:September 13, 1997
Availability:Release the entire work for Virginia Tech access only.
After one year release worldwide only with written permission of the student and the advisory committee chair.

Abstract:

A study aimed at determining the thermal deformation response and thermal buckling loads of rectangular grid-stiffened composite panels is presented. Two edge conditions are considered for the panel, one in which all panel edges are free to deform, and another when all the edges are restrained. In the first case panel deformations due to a uniformly distributed thermal load are analyzed. In the latter case, thermal loads causing buckling failure due to the suppressed in-plane deformations are determined.

The panel is composed of a skin and a network of stiffeners, which are all made of the same graphite-epoxy composite material. Kirchhoff's Theory is used to determine the pre-buckling deformations and load distributions of the composite laminates for a panel with free to deform edges. To illustrate both the in-plane and out-of-plane deformations of plate structures under uniform thermal loads, two thermal coefficient vectors, thermal expansion and thermal bending coefficient vectors are introduced.

Linear panel buckling analysis performed by assuming a linear undeformed prebuckling state. Rayleigh-Ritz Method, which utilizes minimization of the total energy of a structure to determine the buckling loads, is used to govern the buckling analysis of composite laminates forming the panel. Lagrange Multiplier Method is used along with the Rayleigh-Ritz Method to enforce the deformation continuity constraints at discrete locations along the skin and stiffener interface.

As a result, graphical and numerical presentations of the effects of skin and stiffener laminate stacking sequences on the thermal deformations and on the thermal buckling load of the grid-stiffened panel are given.


List of Attached Files

Thesis.tar.Z etd1.pdf etd2.pdf

At the author's request, all materials (PDF files, images, etc.) associated with this ETD are accessible from the Virginia Tech network only.


The author grants to Virginia Tech or its agents the right to archive and display their thesis or dissertation in whole or in part in the University Libraries in all forms of media, now or hereafter known. The author retains all proprietary rights, such as patent rights. The author also retains the right to use in future works (such as articles or books) all or part of this thesis or dissertation.