Indian design code for slender reinforced concrete columns

• Main Author: Lau, Lewis Kah Cheong.
• Other Authors: Chuang Poon Hwei
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Civil engineering::Structures and design
• Online Access: http://hdl.handle.net/10356/52799
• Institution: Nanyang Technological University

This report evaluates the Indian design code IS 456:2000 for slender reinforced concrete columns, by analyzing the failure loads of pinned-ended columns under short term loading and uniaxial bending. The report also aims to study the influences of parameters such as slenderness ratio, eccentricity ratio, concrete strength, reinforcement strength and steel ratio. 150 columns in seven experimental investigations carried out in the past by other researchers were analyzed. The slenderness ratio of the columns ranged from 29.35 to 115.00, eccentricity ratio from 0.00 to 1.00, reinforcement ratio from 0.64% to 5.24%, compressive concrete strength from 16.2MPa to 97MPa, and steel yield strength of 271MPa to 625MPa. When compared to experimental results, the failure loads predicted by IS 456:2000 are found to be unconservative, specifically in slender columns with high eccentricity ratio and low length-to-depth ratio, the code is found to overestimate load capacity. When compared to other codes of practice, namely BS 8110 and EC 2, and theoretical methods, namely transformation method and P-delta method, IS 456:2000 gives the least conservative predictions. IS 456:2000 also demonstrates a decrease in the failure loads when there is an increase in slenderness ratio, an increase in load eccentricities, a decrease in compressive concrete strength and a decrease in steel reinforcement ratio. These behaviours are consistent with the other codes of practice and theoretical methods.