A detailed procedure of mix design for fly ash based geopolymer concrete

The engineering properties of fly ash-based geopolymer concrete have been studied previously but very little work has been conducted on mix design procedures that may be suitable for this new type of concrete. This study proposes a method for selecting the mix proportions of geopolymer concrete which may be suitable for concrete containing fly ash to be used as a cementitious material. Using a flow chart, the paper first describes the procedure in general and then illustrates it using an example. A range of mixes were made to test the method varying water-to-geopolymer solid ratio. It was found that certain basic principles established for conventional concrete still apply for geopolymer concrete mix designs. A simple graphical relationship between 28-day and 7- day compressive strengths of geopolymer concrete is also presented.