The Water Footprint of Low Emission Advanced Performance Concrete

Increasing population results in significant concrete demand for housing and infrastructure. On the other hand, concrete has several potential environmental impacts including global warming due to CO₂ emissions and energy demand and water scarcity due to water consumption for its production. Therefore, it is crucial to assess environmental concerns in concrete production for sustainable construction. Low emissions advanced performance (LEAP) concrete uses fillers – fine particulates that are inert when mixed with water and cement – as binder replacement to reduce CO₂ emissions and energy consumption. The dilution of binder by a high amount of filler can be compensated by reducing the volume of mixing water needed to achieve concrete desired rheological behavior through packing techniques combined with chemical admixtures -superplasticizers- for adequate particle dispersion. This technology achieves the required compressive strength and rheology while reducing cement’s CO₂ emissions. This study estimates and compares the water to produce LEAP and conventional concrete in order to complement their environmental profile. Water for aggregates and cement production is considered in addition to mixing water. The results are estimated in ranges to include variations due to technological routes. Primary data are used for the LEAP and conventional concrete formulations and data from the industry are used for the water activities other than concrete mixing. The results show LEAP concrete to have slightly lower water consumption than conventional concrete which together with low CO₂ emissions suggests that this is a potential solution for sustainable construction, however, further analysis is needed.