Desai, R. K.
Design aids for reinforced concrete circular columns with high strength steel - Vol.97(4), Apr - Mumbai ACC LTD 2023 - 17-26p.
Circular reinforced concrete columns provide good aesthetics. Circular columns will have same moments of inertia about any diametrical axes, resulting in same strength and stiffness about any of the diametrical axes of bending. Interaction curves are an inevitable requirement for design of columns subjected to axial load and moments. Design aids are available for Fe-415 and Fe-500 grades of steel in many text books and handbooks. Design aids published by Bureau of Indian Standards have been very useful for the designers from the past four decades. However, the design aids in the form of interaction curves for columns with high strength steels like Fe-550 and Fe-600 grades are scarce. With the availability of high strength steels, the usage of the same is increasing. Considering this requirement, an attempt is made in this paper to derive the required mathematical formulae and suggest a systematic step by step procedure to formulate interaction curves for circular columns with any grade of steel. As the procedure suggested involves iterative computations using a systematic approach, it is wellsuited to be developed as a computer program. The typical output of such a program has been validated and presented for circular columns for HYSD Fe-600 grade of steel in the form of interaction curves. The mathematical formulae and the step by step procedure suggested can be easily modified for circular columns subjected to axial tension and moment. The formulae and step by step procedure presented here are so generic in nature that, once the design stress-strain curve of steel is known, interaction curves can be plotted for any grade of steel including mild steel, high yield strength deformed (HYSD) bars and thermo-mechanically treated (TMT) bars.
Civil Engineering
Design aids for reinforced concrete circular columns with high strength steel - Vol.97(4), Apr - Mumbai ACC LTD 2023 - 17-26p.
Circular reinforced concrete columns provide good aesthetics. Circular columns will have same moments of inertia about any diametrical axes, resulting in same strength and stiffness about any of the diametrical axes of bending. Interaction curves are an inevitable requirement for design of columns subjected to axial load and moments. Design aids are available for Fe-415 and Fe-500 grades of steel in many text books and handbooks. Design aids published by Bureau of Indian Standards have been very useful for the designers from the past four decades. However, the design aids in the form of interaction curves for columns with high strength steels like Fe-550 and Fe-600 grades are scarce. With the availability of high strength steels, the usage of the same is increasing. Considering this requirement, an attempt is made in this paper to derive the required mathematical formulae and suggest a systematic step by step procedure to formulate interaction curves for circular columns with any grade of steel. As the procedure suggested involves iterative computations using a systematic approach, it is wellsuited to be developed as a computer program. The typical output of such a program has been validated and presented for circular columns for HYSD Fe-600 grade of steel in the form of interaction curves. The mathematical formulae and the step by step procedure suggested can be easily modified for circular columns subjected to axial tension and moment. The formulae and step by step procedure presented here are so generic in nature that, once the design stress-strain curve of steel is known, interaction curves can be plotted for any grade of steel including mild steel, high yield strength deformed (HYSD) bars and thermo-mechanically treated (TMT) bars.
Civil Engineering