par Vilquin, Thomas
Référence International Conference on Structures and Architecture(juillet 2013: Université de Minho, Guimarães, Portugal), Structures and Architecture, CRC Press, Leiden
Publication Publié, 2013-07-01
Publication dans des actes
Résumé : Structural design should be in the hands of architects, for at least 2 reasons. One is that including the development of a structural concept amidst architectural design as a whole allows the architect undertaking the form of the structure that will be necessary, and to organically merge it with the formal intentions. Secondly, thanks to such a sensible design, one can achieve a structure (that accounts for the major part of the weight of a building) comprising a moderated amount of matter (and thus energy, as well). Through that mastering of the consumption of resources, sustainability is promoted.But how to teach structural design to architecture students? The problem is that the generation of building engineers the present teachers are part of was directly thrown into the computer era. Indeed, numerical models were accurate enough for structural dimensioning. Thus, the methods we could think of at first are all analytical and numerical that is, totally inadequate for architecture students.Then we incidentally became aware of the use of physical models in pre-computer times, which seemed interesting because it was using a language architects are familiar with. Besides, it seemed fitter than graphostatics, because it allows easily apprehending 3-dimensional effects, as well as structures that do not work mainly in traction/compression, making it applicable to virtually the whole spectrum of structural concepts a student could come with. On the other hand, it does not provide absolute quantitative results, but the goal here is morphological design (including its proportions), and not dimensioning.Yet, it appeared that this method was then mainly used by engineers, with focus on material properties representation (with costly materials like resins) and displacement and stress measurement. The method was also used by architects (for instance, professor Jean-François Pirson in Liège), but the corresponding publications center more on the philosophy of it rather than its actual application. Finally, references could be found about pedagogical demonstration models, but they led to solid, expensive materials, unpractical for testing numerous structural alternatives.The conclusion was that just an exhumation of the technique would not be appropriate: a translation had to be performed. This proved possible by exploring through experimentation itself the conditions of its righteous application. The various questions at hand were: what are the general rules to be respected? what part of the structure has to be modeled in order to study a given structural element? And at what scale? what technologies could be thought of in order to easily and efficiently model the structure, its connexions and the loads? what are the methods of analysis of the models?Some answers could be highlighted.A peculiar feature has been to combine the physical model with a simple, 2D numerical one, providing extra information about the internal efforts.As a conclusion, learning to correctly apprehend the structural dimension of their project through a physical model has significantly empowered the students on that ground, in a way that could be transferred further to their later practice.