On the prediction of topology and local properties for optimal trussed structures

Abst rac t A new formulation is presented for mathematical modelling to predict he distribution of material, material prop-erties, and topology for the optimal design of trussed structures. The design problem is cast in a form to minimize ameasure of gen-eralized compliance, which is calculated as a sum over the structure of weighted displacement. Member stiffnesses appear as design variables and, starting with a given ground structure, the solu-tion predicts the optimal layout and distribution of stiffness. The isoperimetric constraint in the reformulated problem measures to-tal cost in generalized form, based on independently specified unit relative cost factors for each truss element. One or another form of optimal design is generated via a process where designated el-ements in the unit relative cost field are adjusted systematically at each cycle. The generalized cost feature provides as well for the introduction of certain technical constraints into the desig