The principal problem that must be solved when integrating CAD and CAE is to devise an algorithmic exchange of information between the two subsystems. Elsewhere, we have argued that higher-level representations can be instrumental to lowering functional barriers between CAD, CAE and process planning. In this paper, we argue our view in more detail by a case study, and focus in particular on the nature and structure of the information required to solve both the shape design as well as the performance analysis. The domain we consider in this case study is structural steel design. When approached within traditional engineering practice, this area of design is mature and well-understood. But when departing from the usual repertoire of standard beams and joints to connect them, there is a transition to the frontiers in structural analysis, and many challenging problems remain open.