Abstract

In concrete fire resistance design, the mechanical performance of both reinforced and non-reinforced concrete is pivotal. This research evaluates the influence of different elevated temperatures and exposure time on the mechanical properties of Reinforced Concrete Beam (RCB).The compressive, split tensile and flexural strengths of M15 concrete mix, reinforced with 12mm steel bar were tested at different aging days 7,14 and 28days with varying temperature of 0 oC,100oC, 150oC, 200oC and 250oC respectively. Linear model was developed. The result reveals that the overall strength of concrete reduces with increase temperature. The compressive strengths obtained at varying temperature at 28days are 15.2N/mm2 , 14.21N/mm2 ,13.97N/mm2 and 11.05N/mm2 respectively, split tensile strengths are 2N/mm2 , 1.85N/mm2 , 1.71N/mm2 , 1.3N/mm2 and 1.53N/mm2 also Flexural Strength are 4N/mm2 , 3.65N/mm2 , 3.06N/mm2 and 2.77N/mm2 . The model provides insight to the relationship between temperature and the strength. These models could be incorporated into codes for reinforced concrete structures.

Copyright of the paper named above is hereby assigned and transferred to the Nigerian Journal of Applied Science and Innovative Technology published by College of Engineering, Bells University of Technology, Nigeria.