Flexural effect of flange width variation of ferrocement-cold-formed steel section as a composite beam

Abstract

Structural Composite beams are known to be economical since the savings in steel can reach up to 50% by weight over non-composite beams. The composite action can be achieved by achieving the shear connection between the beam and the concrete using the shear connectors, however, the composite construction have been well established for hot-rolled steel members and yet to be studied and researched for cold formed steel beams. This paper presents the ability of the cold formed lipped C-channel section to be used as a composite beam with Ferrocement slab. The shear connection is developed by using shear bolts size 12mm diameter which were being tested and proven to create adequate shear connection. Three variations of the ferrocement flange were tested for bending and compared with the bending capacity of the bare coldformed steel beam. British standards 5950-3.1 and 5950-5 were used for analytical calculation to validate the laboratory results. The laboratory results showed significant increase in the flexural strength of the composite beam compared with the bare cold form steel beam. However, this increase dropped as the width of the beam’s flange increased. Experimentally, the results show the significant increase in the flexural strength of the composite beam when compared with the bare cold-formed steel beam of 75.9%, 84.9% and 119% for the CF200, CF250 and CF300 respectively. Theoretically, the increase in the flexural strength of the composite beam when compared with the bare cold-formed steel beam was 52.9%, 62% and 73.8%. This study has also the effect of using the ferrocement in delaying the cracking of the beam by providing more stress resistance in the flange that reached 33.24 N/mm2