Effect of Curing Temperatures and NAOH Concentrations on Compressive Strength of Geopolymer Pastes Produced From Elaziğ Ferrochrome Slag
Recently, an increasing interest has been appeared for geopolymer as a binding material because of the benefits
that it brings via, using of industrial waste materials such as ferrochrome slag, fly ash, blast furnace slag and reduction in
greenhouse gas emission caused by cement production. The objective of the present work is to investigate effect of different
NaOH concentrations and curing conditions on mechanical properties geopolymer pastes produced from Elazığ ferrochrome
slag (EFS). EFS was alkali activated with NaOH solutions prepared with different molarities (8, 10, 12, 14 and 16M).
Liquid/binder ratio was determined as 0.28 experimentally. Specimens produced in this way were cured at 50, 100, 150°C
and laboratory conditions for 72h. For each specimen produced using this different parameters, the change in compressive
strength was determined with time (3 to 28 day) for geopolymer pastes which were both cured in laboratory conditions and
cured in oven three different curing temperatures. Additionally, ultrasonic pulse velocity values of geopolymer paste samples
were obtained. The values obtained from compressive strength tests proved that there is an significant effect of different
curing temperatures on mechanical properties of samples. It was also observed that the molarity of NaOH has a considerable
effect on compressive strength. Overall results indicated that the mechanical properties of EFS based geopolymer pastes
were significantly affected by different molarity of NaOH and curing temperatures.
Keywords - Geopolymer paste, Elazığ ferrochrome slag, compressive strength, UPV