Effects of Curing Temperature and Superplasticizer on Workability and Compressive Strength of Self- Compacting Geopolymer Concrete

This experimental work focuses on the effects of super
plasticizer and curing temperature on the workability and
compressive strength of self-compacting geopolymer concrete
(SCGC). SCGC is an improved way of concreting execution that
does not require compaction and is made by complete elimination of ordinary portland cement content. The parameters investigated were superplasticizer (SP) dosage and curing temperature. SCGC were synthesized from low calcium fly ash,activated by combinations of sodium hydroxide and sodium silicate solutions, and by incorporation of superplasticizer for self compactability. The SP dosages were 3%, 4%, 5%, 6% and 7% and the different curing temperatures were 60oC, 70oC, 80oC and 90oC. The effects of SP dosage on workability properties such as
filling ability, passing ability and resistance to segregation were evaluated. The fresh properties were measured using slump flow,T-50 V-funnel, L-Box and J-ring test methods. The essential workability requirements for self compactability according to European Federation of National Associations Representing Producers and Applicators of Specialist Building Products for Concrete (EFNARC) were satisfied. Results showed that the workability and compressive strength improved with the increase in Super plasticizer dosage. An increase in strength was observed
with the increase in curing temperature up to 70oC. However, the strength decreased when the curing temperature increased
beyond 70oC. The compressive strength of 51.52MPa was
obtained for SCGC with SP dosage of 6% and cured at 70oC
oven temperature.