Home > Published Issues > 2014 > Volume 3, No. 3, August 2014 >

Studies on Post Peak Flexural Strength of Concrete under Sustained Elevated Temperatures

K Anbuvelan
Department of Civil Engineering, Jerusalem College of Engineering, Chennai- 600100, India

Abstract—Concrete behavior upon exposure to high temperature or fire is determined by cement matrix, aggregate, moisture content, pore structure, and applied loading in addition to temperature increase rate as well as maximum temperature reached. Plain concrete mixtures exposed to heat showed evidence of surface spalling and cracking. The manifestation of such effects was exacerbated by low permeability and high brittleness of the low water-cement ratio concrete mixture used. Effect of heat and temperature upon concrete is attributed to internal pressure caused by water evaporation. Typically, water vapor is not drained through concrete pours at a fast rate so that internal pressure below the point of potential damage to the microstructure is reduced. Incorporation of Polypropylene fibers in Concrete, reduces the spalling and cracking. This was achieved via melting and consequently, creating added escape routes for vapor pressure. In this work an attempt has been made to study the effect of exposure to elevated temperature upon fibrillated polypropylene fiber reinforced concrete. The percentage of fiber considered for these investigations are 0.0%, 0.1%, 0.2% and 0.3% by volume of concrete mix at 100¡ãC, 150¡ãC, 200¡ãC and 250¡ãC for a sustained duration of 2 h, 4 h and 6 h, of exposure. The tests have been carried out as per recommended procedures of relevant codes and previous investigators. The results are compared and conclusions are arrived.

Keywords: Flexural strength, Fiber Reinforced Concrete, Polypropylene fiber, Sustained elevated temperature
Cite: K Anbuvelan, "Studies on Post Peak Flexural Strength of Concrete under Sustained Elevated Temperatures," International Journal of Structural and Civil Engineering Research, vol. 3, no. 3, pp. 133-141, 2014.