On the analysis of membranes stretched over a unilateral support by B.E.M.

The resolution of membranes stretched over a unilateral, frictionless, rigid (or deformable obstacle) is considered by employing BE methods and performing a suitable domain discretization of the unknown support reaction. As in the case of domain-type techniques algebraic formulations in the form of a linear complementarity problem are obtained, whose coefficient matrices are shown to be symmetric negative definite 'up to the discretization errors'. The problem could also be solved by making a constrained Trefftz functional stationary, from which, by means of an indirect BE method, a linear complementarity problem with a symmetric coefficient matrix follows directly.