Abstract
In this paper, we use uniform quartic polynomial splines to develop a new method, which is used for computing approximations to the solution and its first, second as well as third derivatives for a system of fourth order boundary value problems associated with obstacle, unilateral and contact problems. It is shown that the present method is of order two and gives approximations which are better than those produced by other collocation and finite difference methods. Numerical examples are presented to illustrate the applicability of the new method.