Abstract—This study investigates the mechanical and
microstructural characterization of alkali-activated fly ash/slag
(AAFS) mortars with various ratios of fly ash to slag. The
liquid/binder ratios of 0.35, 0.5 and 0.65 are considered for the
AAFS mortars. 4% Sodium oxide (Na2O) concentration of
cementitious material weight in mixture and liquid sodium
silicate with modulus ratio (mass ratio of SiO2 to Na2O) of 1
were used as alkaline activators to alkali-activate various fly
ash/slag ratios. Compressive strength test, water absorption test,
drying shrinkage test, scanning electron microscopy (SEM) and
X-ray diffraction (XRD) analysis were conducted. Test results
reveal that both fly ash/slag ratio and the liquid/binder ratio are
two significant factors influencing the mechanical and
microstructural characterization of AAFS mortars. The
hydration products of AAFS mortars are mainly amorphous
alkaline aluminosilicate and low-crystalline calcium silicate
hydrate gel.
Index Terms—Alkali-activated fly ash/slag, liquid/binder
ratio, scanning electron microscopy (SEM), X-ray diffraction
(XRD).
Maochieh Chi is with the Department of Fire Science, WuFeng
University, Chiayi County, 621 Taiwan (e-mail: jackchi@wfu.edu.tw).
Yenchun Liu is with the Graduate School of Opto-Mechatronics and
Materials, WuFeng University, Chiayi County, 621 Taiwan (e-mail:
blliu@wfu.edu.tw).
Ran Huang is with the Department of Harbour and River Engineering,
National Taiwan Ocean University, Keelung, 200 Taiwan (e-mail:
ranhuang@mail.ntou.edu.tw).
[PDF]
Cite: Maochieh Chi, Yenchun Liu, and Ran Huang, "Mechanical and Microstructural Characterization of
Alkali-Activated Materials Based on Fly Ash and Slag," International Journal of Engineering and Technology vol. 7, no. 1, pp. 59-64, 2015.
