Masters Theses

Harold Costa

Keywords and Phrases

Composites; Functionally graded; Sandwich panels; Stability; Wrinkling

Abstract

"Benefits of a functionally graded core increasing wrinkling stability of sandwich panels have been demonstrated in a recent paper [1] where a several-fold increase in the wrinkling stress was observed, without a significant weight penalty, using a stiffer core adjacent to the facings. In the present paper wrinkling is analyzed in case where the facings are subject to biaxial compression and/or in-plane shear loading and the core is arbitrary graded through-the-thickness. Two issues addressed are the effect of biaxial or in-plane shear loads on wrinkling stability of panels with both graded and ungraded core and the verification that functional grading of the core remains an effective tool increasing wrinkling stability under such two-dimensional loads. As follows from the study, biaxial compression and in-plane shear cause a reduction in the wrinkling stress as compared to the case of a uniaxial compression in all grading scenarios. Accordingly, even sandwich panels whose mode of failure under uniaxial compression was global buckling, the loss of strength in the facings or core crimpling may become vulnerable to wrinkling under two-dimensional in-plane loading. It is demonstrated that a functionally graded core with the material distributed to increase the local stiffness at and close to the interface with the facings is effective in preventing wrinkling under arbitrary in-plane loads as compared to an equal weight homogeneous core"--Abstract, page iv.

Advisor(s)

Birman, V. (Victor)

Committee Member(s)

Chandrashekhara, K.
Schonberg, William P.

Department(s)

Mechanical and Aerospace Engineering

Degree Name

M.S. in Aerospace Engineering

Publisher

Missouri University of Science and Technology

Publication Date

Summer 2017

Pagination

xi, 52 pages

Note about bibliography

Includes bibliographical references (pages 47-49).

Rights

© 2017 Harold Costa, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Thesis Number

T 11476

Electronic OCLC #

1104293855

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