Effect of curing, fibre content and exposures on compressive strength and elasticity of UHPC

• Published in: Advances in cement research 2015-01, Vol.27 (4), p.233-239
• Main Authors: Ahmad, Shamsad, Hakeem, Ibrahim, Azad, Abul Kalam
• Format: Article
• Language: English
• ISSN: 0951-7197; 1751-7605
• DOI: 10.1680/adcr.13.00090

The paper presents an experimental study on the evaluation of the compressive strength and modulus of elasticity of ultra-high performance concrete (UHPC) prepared with varying steel fibre contents, cured in water and exposed in air, and subjected to three exposure conditions (after 28 d of curing): laboratory environment, alternate heating–cooling cycles (heating at 60°C for 2 d and then cooling at room temperature for 2 d), and alternate wet–dry cycles (wetting for 2 d in aggressive salt solution and then drying at 30°C for 2 d). The test results indicate that: (a) although water-curing is better than exposure in air in improving the strength, the difference is not significant, particularly at a higher fibre content, (b) an increase in the fibre content can improve the strength and modulus of elasticity up to a certain extent, but beyond that an increase in the fibre content is not proportionally beneficial and (c) the effect of 6-month exposure to wet–dry and heating–cooling cycles on the strength and modulus of elasticity is negligible; indeed, the heating–cooling cycled specimens have strength and modulus of elasticity higher than the specimens not subjected to the cyclic exposures.