Suitability of cement combinations for carbonation resistance of structural concrete

Abstract

Purpose

This paper aims to assess the suitability of cement combination containing CEM I, fly ash, silica fume and metakaolin for durability design against carbonation-induced corrosion in concrete.

Design/methodology/approach

Cube compressive strengths at 28 days and accelerated carbonation depths at 28 days and at various exposure ages were determined at the water/cement ratios of 0.35, 0.50 and 0.65. To assess their suitability for carbonation-induced corrosion, the material costs and embodied carbon dioxide (eCO₂) contents of the concretes at equivalent performance were compared.

Findings

Cement combination concretes achieved equal carbonation resistance with CEM I at higher compressive strengths, lower water/cement ratios and higher cement contents. The comparison of the concretes, at equivalent performance, based on the carbonation-induced corrosion exposure classes XC3 and XC4 (Table A.4 of BS 8500-1), shows that ternary and more binary cement concretes have lower costs and eCO₂ contents than those recommended in Table A.6 of BS 8500-1.

Research limitations/implications

This analysis is limited to a working life of 50 years. Further research is needed to verify the suitability of the cement combinations for a working life of 100 years and for the other aspects of durability design covered in BS 8500.

Practical implications

Cement combination concretes have lower eCO₂ content. Hence, when they are cheaper than CEM I concrete at equivalent performance, they would make concrete construction more economic and environmentally compatible.

Originality/value

This research suggests the inclusion of metakaolin and ternary cement combination concretes in BS 8500 for durability design against carbonation-induced corrosion.

Citation

Olufemi Folagbade, S. and David Newlands, M. (2014), "Suitability of cement combinations for carbonation resistance of structural concrete", Journal of Engineering, Design and Technology, Vol. 12 No. 4, pp. 423-439. https://doi.org/10.1108/JEDT-08-2012-0033