Synergetic effect of biomass fly ash on improvement of high-volume coal fly ash concrete properties

Sustainable construction is high on the agenda, especially regarding building materials. Using of by-products or waste materials from other economic sectors as cement replacement material in concrete production seems to be a more sustainable option than applying ordinary Portland cement concrete. The main aim of this work was to evaluate the performance of biomass fly ash (BFA) when used as cement replacement material and as an alkalinity reserve material in high-volume fly ash concrete (HVFAC). Therefore, several compositions of concrete including BFA were tested for compressive strength, water absorption, accelerated carbonation, and chloride penetration resistance. It was noted that when small amounts of BFA were used, HVFAC properties were improved, compared with a high-volume coal fly ash concrete. These new concrete mixtures showed a positive contribution to the quality, durability and sustainability of HVFAC.The authors wish to thank the Portuguese Foundation for Science and Technology (FCT) and the Eco-Construction and Rehabilitation Doctoral Program for supporting the PhD scholarship (reference PD/BD/ 52661/2014). This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R&D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE), under reference UIDB/ 04029/2020