Optimum design of composite laminates with STROPT

Abstract

SUMMARYThe design of a composite laminate involves the determination of layer thicknesses and orientation angles. The problem is posed as the optimum weight (or volume) design of composite laminates which withstand the specified loads without failure. The modified Hill-Mises or Tsai-Wu failure criterion is taken as a constraint, each layer being subjected to this criterion. The design variables considered are the layer thicknesses and orientation angles. Based on the finite-element analysis capability of composite laminates provided by NISA 11. a composite laminate optimization procedure has been developed. Nonlinear optimization techniques are used to approach the optimum design of the composite laminates. Efficient design sensitivity analysis procedures are implemented based on the direct differentiation and adjoint variable methods. Example problems illustrate that the program offers an efficient and practical design tool for composite laminates.

Optimum Design of Composite Structures: A Literature Survey (1969–2009)

“…The problem is to find the design resulting in the minimum value for an undesired feature or response of the structure or the maximum value for a desired feature. Accordingly, in some of the studies, the goal was to minimize laminate thickness, 12,17,35,38,59,60,64,83,84,110,129,136,143,155,157,165,170,174,188,191,206,211,225,234,253,254,259,265,267,268,282,286,293,315,317,319,333,343–345,350,351,360,379,380,387,396,408,410,411,415,428,438,498,501,505,535,539,541,592,595,617,…”

“…In order to check whether a configuration generated by optimization algorithm for the composite structure will result in satisfactory performance, one should use a reliable failure criterion. As intralaminar static failure criterion, the researchers used Tsai-Wu, 64,68,78,83,109,110,128,130,155,174,197,205,209,211,217,218,223,233,234,244,252,261,266,269,276,277,309,319,321,326,339,342,355,360,365,371,387,394,398,403,411–414,439,444,447,451,452,456,477,483,484,489,490,510,511,519,522,529,532,535,…”