Characterization of optimum fluidized bed combustion ash-based geopolymer concrete

Abstract

The fluidized bed combustion (FBC) ash was evaluated for value-added use in the production of geopolymer concrete where alkali aluminosilicate hydrates are the primary binder constituents. The FBC was supplemented with other raw materials in order to achieve chemical balance, and they were milled with CO2 and air to evaluate the benefit from CO2 uptake. An experimental study on the properties of the optimum FBC ash-based hydraulic cement and the concrete fabricated from it was conducted. Also, the corresponding properties of Portland cement concrete were also investigated as the reference group. For the FBC ash-based cement, tests were performed to measure the CO2 uptake and heat of hydration; for FBC ash-based hydraulic cement concrete, measurements were made on the compressive strength of hardened material, residual compressive strength after immersion in boiling water and sulfates resistance. The results of this study suggest that, the FBC ash-based geopolymer with the mechanicochemical aviation can provide desired mechanical attributes, sulfates resistance when compared with normal Portland cement concrete.