LEXURAL CAPACITY OF COMPOSITE BEAMS USING TRUSS BEAMS

An experimental study was made to assess the flexural capacity of Composite Beams using Truss beams under two point loading with span 2m. Beam consist of top and bottom chord with cold formed light gauge steel plate ( width 100 mm and thickness varying from 1.5mm to 2mm) and light gauge angle section welded at the ends of the plate. Top and bottom chord members were connected by steel rods of diameter 8mm making inclined connections with horizontal using Fe 250 g rade steel at both faces of angle s. Truss was filled with M25 concrete to form a Composite Beam. A comparitive study was made between truss beam and composite beam to assess the ultimate load carrying capacity, Flexural strength, Ultimate Deflection, di splacement ductility. Tests were conducted on truss beams and composite beams for different thickness. From the result it was observed that for truss beams as the thickness varied from 1.5mm to 2mm load carrying capacity increased by 1.08 times but when t he same truss beam encased by concrete load carrying capacity raised by 2.26 times. When concrete was encased and thickness was increased load carrying capacity increased by 2.6 times. As the thickness increases from 1.5 to 2mm displacement ductility fact or increased by 4.8% for truss beam but when concrete is encased displacement ductility factor get increased by 76.47% . Flexural strength of composite beam is 2.46 times more than truss beam when the thickness of light gauge cold formed steel plate is 2m m and when the thickness of light gauge cold formed steel plate is 1.5mm Flexural strength of composite beam is 2.27 times more than the flexural strength of truss beam. A marginal increase in load carrying capacity, flexural strength, displacement ductil ity occurs after encasing concrete