Optimum laminate design for strength and stiffness

Abstract

SUMMARYA method is presented for minimum weight optimum design of symmetric fibre-composite laminates subject to multiple in-plane loading conditions which takes into account membrane stiffness requirements and strength limitations. The problem is cast as a non-linear mathematical programming problem in which the thicknesses of material placed at preassigned orientation angles are treated as the only design variables. The non-linear programming formulation is transformed into a sequence of linear programs employing an adaptation of the method of inscribed hyperspheres in which only critical and near critical constraints are considered at each stage in the procedure. Example applications illustrate that the method presented offers an efficient and practical optimum design procedure for the fundamental and recurring problem treated.

Particle swarm optimization approach for multi-objective composite box-beam design

“…In [1,2], the design variables are considered as continuous variables and the optimization problem was solved using conventional optimization algorithms.…”

Initiative in Concurrent Engineering (DICE). Phase 1.

“…Assuming the laminate to be balanced and symmetric and given the ply angles, the optimization problem is formulated as one of determining the ply thicknesses which would minimize the plate weight subjected to strength and stiffness constraints. '-his type of composites design problem has also >Jeen studied previously by several other researchers [4][5][6]. The results obtained are presented in Table 1.…”

Determination of maximum negative Poisson's ratio for laminated fiber composites

“…This returns to the reduction of heavy calculation of a repetitive optimization algorithm [18]. The angle of the fibers is predetermined in this study and they are chosen so that they are approximately capable of having (covering) all the values between 0 and 908 (Fig.…”

“…Schmit and Farshi [18] introduced an optimization technique based on the thickness of laminas for optimum stiffness and strength of composite laminates. Callahan and Weeks [19] used a genetic algorithm (GA) to find the optimal fiber orientations and stacking sequences of laminated composites for their maximum strength and/or stiffness.…”