In solid mechanics, engineers and scientists are faced to a large class of nonsmooth phenomena. A common feature to these problems is that they are unilateral, in the sense that their formulation and modelling require a systematic use of inequalities.

This colloquium is a joint-meeting of two groups. The first one (Limit states of materials and structures-direct methods) is active in plastic limit analysis and its powerful extension to variable repeated loadings called shakedown analysis. The second one (Unilateral Problems in Structural Analysis) is more focused on the formulation of the unilateral problems and in the quest of the most appropriate solution technique in areas such as contact and adherence, friction, interfaces and no-tension materials.

Emphasis will be put on creative ideas, as opposed to technicalities and to purely numerical contributions.