1) The document studies the behavior of cold formed steel built-up columns under uniaxial compression loading using bolted and welded connections.
2) Six cold formed steel columns (three bolted, three welded) were tested and the welded columns showed 40% higher load capacity than manual calculations while bolted showed 28% higher.
3) Both bolted and welded columns performed better than manual calculations that did not consider connections. Welded connections provided higher strength than bolted connections.
4) The study shows that cold formed built-up columns can be an effective and economic alternative to hot rolled sections for lighter loads.