Optimize Of Buckling Stability Of Composite Laminate By Genetic Algorithm

Composite materal is higher not only its ratio of strength to weight and ratio of stiffnes to weight than other materals, but also may freely chang its propertices. That is, structural design and materal design is uniform so as to fully bring into ply its efficiency. As basic component of airplane-composite laminate, it may preferably improve loading ability by layer lay-up optimize design. Because stacking sequence of laminate is discrete variable, it is difficulty that discrete variable is solved by conventional math programming, while Genetic Algorithm may solve optimize problem of dicrete variable. So, Genetic Algorithm is good for optimize of stacking sequence.This paper adopts Genetic Algorithm to solves optimize design of buckling for different restriction, different loading, different thickness and different aspect ratio. The mostly task: firstly, applys subarea generalized variety principle, constitutes place energy equation of composite stiffened plane; compile FORTRAN procedure of buckling of composite stiffened plane to solve critical buckling load of laminate; The critical buckling load of laminate that is solved by ANSYS compares to one that is solved by personal procedure, they are anastornose; Then , I use it as subroutine of Genetic Algorithm, and compile optimize procedure of Genetic Algorithm, and results that are solved by personal program compare to results in the literature; Genetic Algorithm optimizes composite laminate for different boundary condition, different thickness, different loading and different aspect ratio so as to improve critical buckling loading of laminate.This paper obtains the following initial conclusions:1.the optimum designs are easily obtained using GAs without anxiliary information such as derivatives of the objective function or an initial guessing point. The sigle crossover operator ensures the diversity of stylebook space, and hardly destroy a good individual.2.the effect factors of stacking sequence of a composite laminate are obtained under a restriction of improving the critical buckling load by the illustration.(1) the loading conditions of a composite laminate: fiber direction along loading direction is good for improving the critical buckling load of a composite laminate under the other three aspects that is known.(2) the boundary condition of a composite laminate: when requirementa of boundary condition is more, fiber direction along loading direction is good for improving the critical buckling load of a composite laminate under the other three aspects that is known.