Experimental and analytical analysis of spot-welded cold form steel built up section under axial compression

ABSTRACT

The widespread adoption of Cold-Formed Steel (CFS) sections for constructing cost-effective housing and lightweight industrial structures is attributed to their ease of assembly and earthquake-resistant properties. Substantial research efforts have focused on enhancing the cost efficiency of structures by utilizing assembled CFS sections. The effectiveness of these BU-C sections relies on their ability to function in a composite manner, a function influenced by the type and arrangement of connections. The study encompasses both experimental and finite element analysis, involving 27 axial compression tests. These tests were conducted on specimens with varying cross-sections and thicknesses, each tested at different pitches. The experimental findings indicate a significant increase in axial compression load when number of pitch is increased. An ABAQUS-based Finite Element Model (FEM) was formulated and validated against the experimental data, demonstrating consistency in both axial compression load and buckling behavior. This authenticated FEM was subsequently employed for a parametric investigation, exploring the impact of pitch, spot welding thickness, and length on the axial compression capacity of BU-C. The observation was that an increase in pitch enhances the composite behavior of CFS BU-C, leading to a corresponding augmentation in compression capacity.

Keywords
Cold formed steel Sections; Built Up Channels; Spot Welding; Finite Element Model