12.02: High strength steel I‐section arches: Inelastic lateral buckling and moment capacity

Abstract

ABSTRACTLittle research has been reported about high strength steel (HSS) arches and no adequate code provisions are available for their strength design although HSS structures are increasingly used in engineering construction. This paper presents an investigation of global inelastic lateral‐torsional buckling and strength of HSS I‐section arches using a validated finite element model. HSS arches in uniform bending are considered and the yield strength of the HSS used in the investigation is 460MPa, 690MPa, and 960MPa. Initial out‐of‐plane bow and twist imperfections and residual stresses are included in the investigation. It is demonstrated that the HSS influences inelastic lateral‐torsional buckling and strength of HSS arches significantly. The high yield strength of the HSS increases the moment capacity of HSS arches and reduces the difference between their inelastic and elastic lateral‐torsional buckling moments. Formulas for the dimensionless capacity of HSS arches in uniform bending, which is consistent with those in AS4100‐1998 and in Eurocode 3 for mild steel members, are developed. It is shown that the predictions of the new formulas for the dimensionless moment capacities of HSS arches in uniform bending agree with the finite element results very well.