Title

The Use of Optimality Criteria in Automated Structural Design

Description

Research in the field of structural optimization in the past decade has led to the development of a number of methods for the automated design of structures of least weight subjected to a multiplicity of loads. These methods which have been principally based upon the use of various algorithmic forms of numerical search have achieved a considerable measure of success for smaller scale problems. Such methods do suffer from the major disadvantage that computational costs increase rapidly with problem size, tending to impose an economic limit on the complexity of the structures which can be optimized. In order to circumvent these economic limitations, the entire problem of structural optimization has been reviewed. A novel approach to the least weight design of indeterminate structures under multiple loading conditions with strength, displacement and fabricational constraints has been developed which overcomes many of the shortcomings of direct numerical search methods. Details of the new approach, which has dramatically reduced the number of cycles compared with mathematical programming formulations are presented along with examples of applications to the weight optimization of representative structures. The incorporation of other types of constraint conditions is also discussed.

Creator

Gellatly, Ronald A.

Berke, Laszlo

Gibson, Warren

Abstract

Research in the field of structural optimization in the past decade has led to the development of a number of methods for the automated design of structures of least weight subjected to a multiplicity of loads. These methods which have been principally based upon the use of various algorithmic forms of numerical search have achieved a considerable measure of success for smaller scale problems. Such methods do suffer from the major disadvantage that computational costs increase rapidly with problem size, tending to impose an economic limit on the complexity of the structures which can be optimized. In order to circumvent these economic limitations, the entire problem of structural optimization has been reviewed. A novel approach to the least weight design of indeterminate structures under multiple loading conditions with strength, displacement and fabricational constraints has been developed which overcomes many of the shortcomings of direct numerical search methods. Details of the new approach, which has dramatically reduced the number of cycles compared with mathematical programming formulations are presented along with examples of applications to the weight optimization of representative structures. The incorporation of other types of constraint conditions is also discussed.

Corporate Author

Bell Aerospace Company, Division of Textron, Inc.

Air Force Flight Dynamics Laboratory

Report Number

AFFDL TR 71-160 p. 557-590

Report Availability

Full text available

Publisher

Wright-Patterson Air Force Base, OH : Air Force Flight Dynamics Laboratory, Air Force Systems Command and Air Force Institute of Technology, Air University

Date

1973

Type

article

Date Issued

1973-12

Provenance

Bombardier/Aero

Distribution Classification

1

Distribution Conflict

No

DTIC Record Exists

No

Format

1 online resource (34 pages) : ill.

Extent

34

Identifier

AD0785968

Is Part Of

Proceedings of the Third Conference on Matrix Methods in Structural Mechanics: Proceedings of the Conference held at Wright-Patterson Air Force Base, Ohio 19-21 October 1971