Shape design optimization of joining mechanism using doubly curved shell

Methods for shape and topology design sensitivity analysis (DSA) and optimi zation of joining mechanisms, such as spot welding and adhesive bonding, us ing a doubly curved (Hughes-Liu) shell are presented in this article. The m aterial derivative concept of continuum mechanics and the adjoint variable method are used to derive the shape and topology design sensitivity express ions in the domain integral form. The shape optimization is performed to fi nd the optimum locations of spot welds to maximize the stiffness of the str ucture. This optimum design is used as the initial design to perform topolo gy optimization based on a density approach to study the effects of materia l distribution on structural performances. A numerical example, by postproc essing NIKE3D finite element analysis (FEA) code, of shape and topology opt imization is given to demonstrate the validity of the methodologies present ed in this study. (C) 2000 Elsevier Science Ltd. All rights reserved.