Concepts in the mechanics of thin structures

This writing is meant to restitute a year later, to the best of my recollection the contents of a series of six lectures I gave in Udine, at the Centro Internationale di Scienze Meccaniche, within the framework of the Course on Classical and Advanced Theo-Ties of Thin Structures: Mechanical and Mathematical Aspects (June 5-9 2006). For this reason, I have made an effort to keep my presentation style informal and colloquial, even when, here and there, I have added some complementing material. There axe three parts. In the Premiss, I try and explain why and how, to my taste, the mechanics of thin structures should be presented; in particular, I introduce. the direct and deductive approaches and I collect a few bits of history of the latter, in its two main variants, the asymptotic method and the method of internal constraints, Section 2 is devoted to an exposition of the method of formal scaling, a unified approach to classic rod mid plate theories that is an outgrowth of the method of internal constraints. Finally, in Section 3, 1 discuss how to best approximate the stress field in a linearly elastic structure-like body, by exploiting the freedom in the choice of reactive stress fields that maintain the constraints.