Prof Patrick de Wilde from Free University of Brussels, Belgium visited WIT and presented a seminar entitled ‘Conceptual Design of Structures’.

This seminar was mainly directed to architectural engineers facing critical design decisions in the phase of so-called “conceptual design”. The resulting design must yield a structure showing a sound behaviour in both the serviceability limit state (SLS) and in the ultimate limit state (ULS), also meaning that three essential criteria should be satisfied: strength, stiffness and stability (the latter including, if relevant, acceptable dynamic behaviour). However, the question very often remains open as to which of the three criteria is overruling the other ones. This seminar, which was a synthesis of the work of a research group headed by Prof de Wilde, tried to show that a conceptual design methodology can be developed, using the concept of morphological indicators. This methodology gives an answer to the question that very often arises when designing lightweight structures; “design for strength” or “design for stiffness”?