Design enhancement of thin-walled steel beams with improved stiffness and reduced weight

Abstract

Thin-walled beams have been extensively applied for engineering field, such as automotive industry and architecture industry, etc. In modern industry, those light stiffened structures are always preferred by designers or engineers. This paper presents an enhanced design of the thin-walled beam structures which employed 'self-made' rib stiffeners to provide higher stiffness compared to the general designs. The presented method can also be used to develop light structures without losing the stiffness. Three typical thin-walled beam structures are presented in this paper based on their cross section shapes – the L-section beam, the box section beam, and the Z-section beam. The improved designs for the three types of beams are demonstrated and structural analyses results prove that with the rib stiffeners, the ameliorated structures can significantly enhance the torsional stiffness while keeping the bending stiffness. Effects of the rib's shape, size, position, and number on the beam's global stiffness are discussed through a parametric study on the L-section beam and an optimised design is achieved for such beams. Following the design methods, the weight of the presented thin-walled beams can be reduced down to 60%.