Structural optimization of shell structures
Abstract
The objective of the present work was the structural optimization of thin shell structures that are subjected to stress and displacement constraints. In order to accomplish this, the structural optimization computer program DESAP1 was modified and improved. In the static analysis part of the DESAP1 computer program the torsional spring elements, which are used to analyze thin, shallow shell structures, were eliminated by modifying the membrane stiffness matrix of the triangular elements in the local coordinate system and adding a fictitious rotational stiffness matrix. This simplified the DESAP1 program input, improved the accuracy of the analysis, and saved computation time. In the optimization part of the DESAP1 program, the stress ratio formula, which redesigns the thickness of each finite element of the structure, was solved by an analytical method. This scheme replaced the iterative solution that was previously used in the DESAP1 program, thus increasing the accuracy and speed of the redesign. The modified program was used to design a thin, cylindrical shell structure with optimum weight, and the results are reported in this paper.
 Publication:

Computers and Structures
 Pub Date:
 February 1994
 Bibcode:
 1994CoStr..50..499G
 Keywords:

 Computer Aided Design;
 Cylindrical Shells;
 Finite Element Method;
 Iterative Solution;
 Optimization;
 Shallow Shells;
 Stiffness Matrix;
 Structural Analysis;
 Thin Walled Shells;
 Computer Programs;
 Displacement;
 Stress Ratio;
 Torsion;
 Structural Mechanics