TY - GEN
T1 - Effect of Type of Sand on the Flowability and Compressive Strength of Slag-Fly Ash Blended Geopolymer Mortar
AU - Hwalla, Joud
AU - El-Hassan, Hilal
AU - Assaad, Joseph J.
AU - El-Maaddawy, Tamer
AU - Bawab, Jad
N1 - Publisher Copyright:
© 2023, Avestia Publishing. All rights reserved.
PY - 2023
Y1 - 2023
N2 - This paper investigates the influence of the type of fine aggregates on the properties of slag-fly ash blended geopolymer mortar. Twelve mixes were prepared with two types of sand: desert dune sand (DS) and crushed dolomitic limestone sand (CS). Different alkaline activator solution-to-binder (0.50, 0.60, and 0.65) and binder-to-sand ratios (1:2, 1:3, and 1:4) were considered to analyze their effect on the performance of the geopolymer mortar. The properties under investigation included the amount of additional water needed to maintain a flow of 150 ± 2 mm and the 7-and 14-day compressive strengths. Experimental test results showed that an increase in fine aggregates content resulted in a higher additional water demand, regardless of the type of sand used. As a result, the mortar compressive strength decreased by up to 29% compared to mixes with the lowest binder-to-sand ratios (1:2 for DS mixes and 1:3 for CS mixes). An increase in the alkaline activator solution-to-binder ratio reduced the additional water needed to satisfy the target flowability but increased the overall liquid-to-binder ratio. Meanwhile, for optimum compressive strength, DS-based mixes comprised B:S and AAS/B ratios of 1:2 and 0.60, respectively, while those of CS-based mixes were 1:3 and 0.65, respectively. Compared to mixes made with CS, those incorporating DS required the addition of more water to maintain the flowability and experienced up to 81% loss in compressive strength; still, DS-based mixes achieved 14-day compressive strengths exceeding 28 MPa. The experimental findings advocate the use of DS as fine aggregates in the production of slag-fly ash blended geopolymer mortar to be utilized in various construction applications.
AB - This paper investigates the influence of the type of fine aggregates on the properties of slag-fly ash blended geopolymer mortar. Twelve mixes were prepared with two types of sand: desert dune sand (DS) and crushed dolomitic limestone sand (CS). Different alkaline activator solution-to-binder (0.50, 0.60, and 0.65) and binder-to-sand ratios (1:2, 1:3, and 1:4) were considered to analyze their effect on the performance of the geopolymer mortar. The properties under investigation included the amount of additional water needed to maintain a flow of 150 ± 2 mm and the 7-and 14-day compressive strengths. Experimental test results showed that an increase in fine aggregates content resulted in a higher additional water demand, regardless of the type of sand used. As a result, the mortar compressive strength decreased by up to 29% compared to mixes with the lowest binder-to-sand ratios (1:2 for DS mixes and 1:3 for CS mixes). An increase in the alkaline activator solution-to-binder ratio reduced the additional water needed to satisfy the target flowability but increased the overall liquid-to-binder ratio. Meanwhile, for optimum compressive strength, DS-based mixes comprised B:S and AAS/B ratios of 1:2 and 0.60, respectively, while those of CS-based mixes were 1:3 and 0.65, respectively. Compared to mixes made with CS, those incorporating DS required the addition of more water to maintain the flowability and experienced up to 81% loss in compressive strength; still, DS-based mixes achieved 14-day compressive strengths exceeding 28 MPa. The experimental findings advocate the use of DS as fine aggregates in the production of slag-fly ash blended geopolymer mortar to be utilized in various construction applications.
KW - compressive strength
KW - dune sand
KW - flow
KW - fly ash
KW - geopolymer
KW - limestone
KW - mortar
KW - slag
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U2 - 10.11159/iccste23.115
DO - 10.11159/iccste23.115
M3 - Conference contribution
AN - SCOPUS:85166190183
SN - 9781990800221
T3 - International Conference on Civil, Structural and Transportation Engineering
BT - Proceedings of the 8th International Conference on Civil, Structural and Transportation Engineering, ICCSTE 2023
PB - Avestia Publishing
T2 - 8th International Conference on Civil, Structural and Transportation Engineering, ICCSTE 2023
Y2 - 4 June 2023 through 6 June 2023
ER -