A VARIATIONAL INEQUALITY AND QUADRATIC-PROGRAMMING APPROACH TO THE SEPARATION PROBLEM OF STEEL BOLTED BRACKETS

A variational inequality and quadratic programming approach is herein proposed for the investigation of the separation problem of steel bolt ed brackets. By applying the classic unilateral contact law to describ e the separation process along the contact surfaces between the bracke t and the column flange, the continuous problem is formulated as a var iational inequality or as a quadratic programming problem. By applying an appropriate finite element discretization scheme, the discrete pro blem is formulated as a quadratic optimization problem with inequality constraints which, in turn, can be effectively treated numerically by means of an appropriate quadratic optimization algorithm. The applica bility and the effectiveness of the method is illustrated by means of a numerical application.