Design of steel I-beams curved in plan to BS 5950

Abstract

This paper is concerned with the strength design of class 1 and class 2 steel I-beams that are curved in plan under vertical (or transverse) loading. It proposes and exemplifies straightforward lower bound interaction equations for designing steel I-beams curved in plan against combined bending and torsion actions, which are both easy to use and consistent with the corresponding methods of BS 5950 for designing steel members subjected to bending. The interaction equations incorporate the significant effects of the included angle and the secondary minor axis bending and torsion actions, and allow for different configurations of lateral bracing. The use of the proposed interaction equations will facilitate the strength design of steel I-beams curved in plan, and lead to safe and more economical structures.