Effect of mix composition on workability and compressive strength of self-compacting geopolymer concrete

Concrete performance expectation has risen to satisfy the ever increasing societal needs alongside with the advancement of technology. Self-compacting geopolymer concrete (SCGC) is an improved way of concreting execution that does not need compaction and it is made by complete elimination of ordinary Portland cement content. This paper reports results of an experimental study on workability and development of compressive strength of SCGC prepared by thermal reaction of low calcium fly ash with sodium hydroxide, sodium silicate and super plasticizer. The effects of water to geopolymer solids on fresh properties such as filling ability, passing ability and resistance to segregation were studied. The fresh properties were assessed using slump flow, V-funnel, L-box and J-ring test methods. The basic requirements for flowability and resistance to segregation for self compacting according to European Federation of National Associations Representing Producers and Applicators of Specialist Building Products for Concrete (EFNARC) were satisfied. This paper also reports the effects of curing duration and temperature on the compressive strength development. The compressive strength of 51 MPa was obtained for self compacting geopolymer concrete cured at 70 °C for 48 h with water to geopolymer solids ratio of 0.33.