Discrete optimal design of elasto-plastic trusses using compliance and stability constraints

Abstract

In this paper two discrete optimization methods are presented for the minimum volume design of elasto-plastic trusses with given geometry. The design is based on given sets of discrete cross-sectional sizes. Both methods enable the use of the plastic reserve of the truss; the plastic deformations, however, are controlled by compliance constraints on plastic deformations. In the second solution method, the shakedown of the truss is also taken into consideration. The stability of the bars is also controlled by using permissible stresses for compression. The methods are based on continuous optimal elasto-plastic design methods and on the discrete optimization method of elastic trusses using segmental approach. By the iterative application of these methods, solution procedures that use standard linear programming have been developed.