Method For Determining the Cross-Sectional Resistance of Transversely Corrugated Cold-Formed Steel Arches Under Compression

Transversely corrugated cold-formed steel (CFS) arch elements are widely used as self-supporting building roofs. The transverse corrugations and the unusual cross-section shapes complicate the design of such members under compressive loading. Since the current Eurocode does not cover the design rules for CFS arches with transverse corrugations, the objective of this study is to develop a method for determining the effective cross-section of such members under compression load. In total 36 stiffness tests and 27 compression tests were carried out on the corrugated CFS arches with different thicknesses and curvatures. Steel arch profiles with thickness of 1.5 mm has 55% higher ultimate load value than the profiles with 1.1 mm thickness due to a bigger effective area to resist the axial compressive forces. The smaller the steel arch radius is, the more susceptible it is to buckle and stability failure due to the eccentricity of compression load along the curvature. The stiffness is directly proportional to the thickness and inversely proportional to the radius of the steel arches. Based on the thickness and the radius, the correction factors between 0.90 and 1.37 are proposed for determining the resistance of curved steel arches with corrugations. The method developed in this research can be used for designing similar types of arches.