Effects of olive residue biomass fly ash as filler in self-compacting concrete

Fine materials, such as fly ash from coal combustion, have been used to reduce the amount of superplasticizer and to manufacture concrete with standard properties. Because of the pozzolanic contribution of conventional fly ash concrete, fly ash can also be used as a partial substitute for cement. However, no results have ever been published on the use of fly ash as filler. This paper presents the results on the use of fly ash from the combustion of agricultural olive residue pellets as filler in self-compacting concrete. This study analyzed the characteristics of biomass fly ash, which was then used to manufacture specimens and obtain the optimal fly-ash dosage for the concrete. The properties of the reference concrete made with conventional filler and the biomass fly ash concrete were compared, as well as their compressive strength after 3, 7, and 28 days. The laboratory tests showed that the biomass fly ash concrete had a compressive strength that was equal to or greater than that of the reference concrete. These results clearly indicate that biomass fly ash can be used to manufacture high-quality self-compacting concrete. (C) 2012 Elsevier Ltd. All rights reserved.