Preliminar Assessments for Decreasing Cement Content on Concretes Made with Recycled Aggregates
B.L. Damineli, J.M. Pablos
Abstract. Nowadays, Construction and Demolition Waste (CDW) are produced in large volumes every day. Thinking in decreasing landfill disposal, the inclusion of these wastes as recycled aggregates in concrete is an effective strategy since the volume of aggregates required are high. So, this is one of the most studied ways for developing more sustainable concretes. However, the replacement of natural aggregates by recycled aggregates (RA) in concrete often signify an increase in cement content. Considering that cement production is the heaviest environmental burden of concrete, the real sustainability of using RA can be put under check. Increasing cement content is more prejudicial than the disposal of construction waste, at least in places where space for landfills are not a problem. Besides of environmental impact, costs increase too. This study presents preliminary a simple strategy – packing and dispersion of aggregates – that could allow decreasing cement content even using RA in concrete mixtures. Some concretes using current dosage method were designed, with natural aggregates and replacing them by recycled ones. In a third step, mixture with RA were optimized by packing and dispersion of particles. There were achieved concretes with very similar ratio “cement content / compressive strength” (here called Binder Intensity), which signifies same cement use efficiency. A better use of RA depends, rather than their quality, also from better concrete design methods.
Keywords
Concrete, Binder Index, CO2, Recycled Aggregates
Published online , 8 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: B.L. Damineli, J.M. Pablos, ‘Preliminar Assessments for Decreasing Cement Content on Concretes Made with Recycled Aggregates’, Materials Research Proceedings, Vol. 7, pp 725-732, 2018
DOI: https://dx.doi.org/10.21741/9781945291838-70
The article was published as article 70 of the book Non-Conventional Materials and Technologies
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