文档介绍：Composites Science and Technology 63 (2003) 1071–1082
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Optimum design posite structures with curved fiber courses
Levend Parnas*,Su¨ ha Oral, U¨ mit Ceyhan
Department of Mechanical Engineering, Middle East Technical University, 06531 Ankara, Turkey
Abstract
In this study, a new methodology for the optimum design of posites with curved fiber courses is presented. The
objective of the optimization problem is to minimize the weight of posite laminate under stress constraints. The Tsai–Hill
criterion is employed on the first ply failure basis. Layer thicknesses and fiber angles are represented by bicubic Bezier surfaces and
cubic Bezier curves, respectively. Design variables are coordinates of control points of the corresponding Bezier splines. The design
variable linking procedure is used in order to reduce the number of design variables further and to provide symmetry in the design.
The sequential quadratic programming is used in the optimization. The modeling of the laminate is carried out by using three-node
shell finite elements.
# 2003 Elsevier Science Ltd. All rights reserved.
Keywords: Structural optimization
1. Introduction consideration, although the weight of the system does
affect its cost and performance.
The use posite materials in the contemporary Varying the fiber volume fraction and changing the
engineering practice has altered the design process of fiber’s orientation at each point of the structure result in
structures, due to their superior and flexible mechanical a variable posite. Several different approa-
properties. However, since they involve a wide range of ches have been used to create structures with variable
parameters associated with plex behavior, the stiffnesses. Such a technique consists in varying the fiber
design of structures with posites requires volume fraction as a function of position. Leissa and
sophisticated analysis techniques. In addition to shape Martin [1] have solved the vibration and buckling
opti