Behaviour and Properties of Eco-Cement Pastes Elaborated with Recycled Concrete Powder from Construction and Demolition Wastes

Thumbnail Image
Files
materials-14-01299-v2.pdf (4.19 MB)
Identifiers
URI: http://hdl.handle.net/11556/1101
ESSN: 1996-1944
DOI: 10.3390/ma14051299
Publication date
2021-03-08
Authors
Advisors
Journal Title
Journal ISSN
Volume Title
Publisher
Multidisciplinary Digital Publishing Institute (MDPI)
Citations
Google Scholar
Export
Research Projects
Organizational Units
Journal Issue
Abstract
This work analyses the influence of fine concrete fractions (<5 mm) of different natures —calcareous (HcG) and siliceous (HsT)—obtained from construction and demolition waste (C&DW) on the behaviour of blended cement pastes with partial replacements between 5 and 10%. The two C&DW fractions were characterised by different instrumental techniques. Subsequently, their limefixing capacity and the physico-mechanical properties of the blended cement pastes were analysed. Lastly, the environmental benefits of reusing these fine wastes in the manufacture of future ecoefficient cement pastes were examined. The results show that HsT and HcG exhibit weak pozzolanic activity, owing to their low reactive silica and alumina content. Despite this, the new cement pastes meet the physical and mechanical requirements of the existing regulations for common cements. It should be highlighted that the blended cement pastes initially showed a coarser pore network, but then they underwent a refinement process between 2 and 28 days, along with a gain in compressive strength, possibly due to the double pozzolanic and filler effect of the wastes. The environmental viability of the blended cements was evaluated in a Life Cycle Assessment (LCA) concluding that the overall environmental impact could be reduced in the same proportion of the replacement rate. This is in line with the Circular Economy goals and the 2030 Agenda for Sustainable Development.
Description
Keywords
Construction and demolition waste , Supplementary cementitious materials , Circular economy , Eco-efficient cements
Type
journal article
Citation
Caneda-Martínez, Laura, Manuel Monasterio, Jaime Moreno-Juez, Sagrario Martínez-Ramírez, Rosario García, and Moisés Frías. “Behaviour and Properties of Eco-Cement Pastes Elaborated with Recycled Concrete Powder from Construction and Demolition Wastes.” Materials 14, no. 5 (March 8, 2021): 1299. doi:10.3390/ma14051299.