Unilateral problems for nonlinearly elastic plates and shallow shells

Using the topological degree for pseudo-monotone operators of type (S+), we establish a general existence result for variational inequalities of von Karman type, which model unilateral problems for nonlinearly elastic plates. Then, we give a reduced operatorial form of Marguerre-von Karman equations for nonlinearly elastic shallow shells and get a new existence result for this model.