BALDO

BALDO is a computer application that minimizes the volume of an aluminium I-bar. The design variables are the thickness, the length of the web and the flange.

The bar can be under generic law of axial force, shear force and bending moment in the OX and OY axes. The tensile condition takes elastic and linear behavior of the piece into account as much as the local instability of the flange and web or general buckling of the bar. All of those go into the formulation of reference stresses, which should not be surpassed and they should be calculated by the methods indicated in Section 3.4.6 in the manual.

The resulting problem to minimize the cross-sectional area under tensile conditions is non-linear, and BALDO resolves it by means of the following three methods:

• Method of efficient directions
• Method of sequence of linear problems
• Method of sequence of quadratic problems

The codification of these algorithms in code DOT (VR&D Inc., 1995) has been used in BALDO for resolving the problems.