Optimization of shells with laminated stiffeners for minimum weight and maximum buckling load

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Abstract

In this research, the optimization of laminated cylindrical shells with composite ring stiffeners is implemented by the Genetic Algorithm (GA). The objectives seek the maximum general buckling pressure and minimum weight of laminated stiffened shells. The buckling pressure is evaluated using Love’s First-order Shear Deformation Theory (FSDT) and solved using the Rayleigh-Ritz energy method. The research introduces a strain energy formulation for laminated ring stiffeners, in which each ring stiffener may be treated individually and the geometrical dimensions and material properties of the stiffeners may be different from one another. Furthermore, the formulation enables the analyst to optimize the material properties of the stiffeners different from those of the parent shell. The results show that the effect of the material and geometrical properties of the shell and stiffeners on the stiffened shell’s buckling capacity is larger than its weight. Also, the buckling optimization has much greater efficiency than the buckling-weight and weight optimizations.

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References

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Journal of Solid and Fluid Mechanics
Volume 4, Issue 1 - Serial Number 1
March and April 2014
Pages 37-49

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