This thesis concerns integrated methods for structural optimization. Structural optimization is concerned with finding the best structural design while satisfying certain restrictions. We divide structural optimization into a number of subfield, e.g. shape, thickness and topology optimization. In this thesis we present different strategies to combine subfields of structural optimization to obtain integrated methods. The thesis consists of two papers.

Paper I consists of a review of different methods to integrate topology and shape optimization that are presented in the literature. Integrated topology and shape optimization can be divided into to three steps. The first step is topology optimization where a concept of the structure to be is generated. This concept is transfered in the second step to an initial design for shape optimization. The last step is shape optimization where the final shape of the structure is determined.

Paper II presents an implementation of simultaneous shape and thickness optimization in a general finite element software. The shape of the plane domain and the out­ of-plane thickness of the structure are simultaneous varied to obtain an optimal design. With this approach an essentially three dimensional optimization problem is solved by only performing a two dimensional analysis. The paper includes two applications of simultaneous shape and thickness optimization.