This work is devoted to the study of the existence of “regular” solutions for a one-dimensional problem with unilateral constrained gradient in Perfect-Plasticity. The particularity of this problem consists in the fact, that the tools usually employed to prove the Inf-Sup equality between the displacement problem and the stress problem do not work. In a first part, we establish this equality by the mean of a penalty method which employs the theory of the convex functions of measures. In a second part, we find the regular limit loads, between which the displacement problem possesses at least a solution which is in W1,1W^{1,1}, verifiyng the boundary conditions and the constraint on the gradient. We give an example where these loads are infinite. Ce travail est consacré à l’étude de l’existence de solutions régulières pour un problème unidimensionnel, avec un gradient contraint unilatéral en Plasticité Parfaite. La particularité de ce problème réside en ceci que, les outils habituellement employés pour montrer l'égalité entre les problèmes en déplacement et en contrainte ne fonctionnent plus. Dans une première partie, on établit cette égalité au moyen d’une méthode de pénalité, qui utilise la théorie des fonctions convexes de mesure. Dans un deuxième temps, on trouve les charges limites régulières, en deça desquelles le problème en déplacement admet des solutions qui sont dans W1,1W^{1,1}, et qui vérifient les conditions aux bords et la contrainte sur le gradient. On donne aussi un exemple où ces charges limites sont infinies.

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Thierry Astruc

Laboratoire d’Analyse Non-Linéaire Appliquée, UFR Sciences et Techniques Université de Toulon et du Var, BP 132, 83130 La Garde cedex, France

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T. Astruc. “Existence of Regular Solutions for a One-Dimensional Simplified Perfect-Plastic Problem with a Unilateral Gradient Constraint.” Journal of Convex Analysis 4 (1997), No. 2, 257–280. https://doi.org/10.68381/jca04013