Steelworks

Research Paper by N.Balasubramanian,R.B.Karthika and Dr.R.Thenmozhi
Government College Of Technology, Coimbatore-641 013, India

ABSTRACT
This paper comprises of the experimental study of eight double skinned concrete filled steel tubular (DSCFT ) beam columns of concentrically placed circular sections filled with self compacting concrete. Tests on the specimens were made by applying eccentric loads. The main experimental parameters for beam-columns were slenderness ratio and load eccentricity. Testing of specimens investigates the behaviour on load deflection, confinement effect, and the strength of the columns. The experimental observations were shown by load-deflection curves. Various characteristics such as strength, stiffness, ductility and failure mode are discussed. The predicted load versus deformation relationships are in good agreement with beam-column test results. The DSCFT columns in-filled with SCC show good strength and ductility. Modified equations are suggested to find the ultimate compressive strength of DSCFT columns filled with SCC.

Keywords : Composite; Double skinned concrete filled steel tubular columns; D/t thickness, fabrication and casting, load deflection, ductility.

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In BS8110, it states that secondary reinforcement should be provided for beams exceeding 750mm deep at a distance measured 2/3 depth from the tension face. Experimental works revealed that at or close to mid-depth of deep beams, the maximum width of cracks arising from flexure may be about two to three times larger than the width of the same crack at the level of surface where the crack originally forms.

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