Smooth dependence on parameters of solutions and contact regions for an obstacle problem

We consider a class of variational inequalities which includes a model of a beam compressed by a force λ and unilaterally supported by a connected obstacle at the height h. A smooth dependence on parameters λ and h of solutions and intervals of their contact with the obstacle is proved in a neighbourhood of a given solution. The basic idea is to show local equivalence of the inequality with a suitable equation and to apply the implicit function theorem to this equation.  2003 Elsevier Inc. All rights reserved.