Multicriterion optimization of the box section of the main girder of the bridge crane

Abstract

The paper considers the problem of optimization of the box section of the main girder of the bridge crane for the case of placing the rail above the web plate. The method of Lagrange multipliers was used as the methodology for determination of optimum dependencies of geometrical parameters of the box section. The criteria of strength, local stability of plates, lateral stability of the girder, dynamic stiffness, deflection and cost effectiveness were simultaneously applied as the constraint functions. The results were obtained in explicit form, which is very favourable for discussion of solutions. Verification of the obtained results of geometrical parameters was carried out through numerical examples.