Characterization of different biomass ashes as supplementary cementitious material to produce coating mortar

Despite being characterized as a renewable energy source, burning biomass is an environmental problem regarding the disposal of generated by-products. The present work aimed to determine the main properties of Rice Husk Ash, Sugarcane Bagasse Ash and Eucalyptus Chip Ash to evaluate their impacts on the production of ecological mortars with lower cement consumption levels. Therefore, the physicalchemical characterization of biomass ashes and flexural and compressive strength tests, dynamic elastic modulus and capillary water absorption of the mortars produced with 10, 20 and 30% substitution, by mass, of Portland cement were carried out for each of the biomass ashes. It was found that the chemical and mineralogical characteristics presented by the biomass ashes had a significant impact on the results obtained. Considering the high levels of amorphous silica, RHA allowed high levels of substitution without affecting the mortar's physical and mechanical parameters. Although not very reactive, SCBA and ECA maintained the performance of mortars at low levels of incorporation, acting as filling materials (fillers). The results are encouraging for paving the way in terms of using different biomass ashes in rendering mortars. (c) 2021 Elsevier Ltd. All rights reserved.