Behaviour and design of horizontally curved steel beams

Abstract

This paper investigates the behaviour of I-beams curved in plan, and a proposed design method to estimate the ultimate strength of such beams subjected to gravity loading. First, a finite element method for analysing inelastic large-displacement behaviour of a horizontally curved I-beam is presented. The load-displacement and ultimate strength results generated by the finite element method are compared with the theoretical and experimental results published in the literature. The accuracy of the finite element analysis approach is thus established. An investigation is then followed to study the effects of residual stresses and radius of curvature-to-span length ratios on the ultimate strength behaviour of horizontally curved I-beams. An approximate equation is derived and proposed to evaluate the ultimate moment capacity of curved I-beams for several loading and boundary conditions. Based on the derived equation, standard charts are generated for the evaluation of ultimate strength of I-beams with different horizontal curvatures and span-lengths. Behaviour of curved beams with intermediate restraints is also studied both experimentally and analytically. © 1994.