Utilization of waste glass in alkali activated slag/fly ash blends: reaction process, microstructure, and chloride diffusion behavior

Figures & data

Figure 1. X-ray diffractogram of (a) GGBS; (b) FA; (c) GP.

Table 1. Chemical composition and physical properties of waste glass, GGBS, and Fly ash.

Chemical composition	GP (wt. %)	GGBS (wt. %)	FA (wt. %)
Na2O	14.69	/	/
MgO	1.30	8.61	1.10
Al2O3	1.90	13.31	27.17
SiO2	68.73	29.63	51.75
SO3	0.10	2.70	1.10
K2O	0.70	0.40	1.90
CaO	11.99	43.04	5.90
TiO2	0.10	1.50	1.80
MnO		0.40	0.10
Fe2O3	0.40	0.40	8.29
P2O5		/	0.90
Cl	0.10	/	/
LOI^a (1000 °C)	1.36	1.25	2.24
Specific density (g/cm^3)	2.52	2.96	2.38
BET Specific surface area (m^2/g)	0.99	0.37	0.82

^a LOI: loss on ignition at 1000 °C.

Figure 2. The particle size distribution of GGBS, FA, and GP.

Table 2. Formulations of the mortar samples.

Sample	L/S ratio^a	NaOH (mol/L)	GGBS (wt. %)	FA (wt. %)	GP (wt. %)
Ref	0.4	4	70	30	0
GP10	0.4	4	70	20	10
GP20	0.4	4	70	10	20
GP30	0.4	4	70	0	30

^a L/S ratio: liquid to solid ratio.

Solid = Weight (GGBS + FA + GP).

Table 3. The elemental molar ratio of samples (without activator).

Sample	Al/Si	Na/Si	Ca/Si	Na/Al	Mg/Al
Ref	0.28	0	0.94	0	0.93
GP10	0.23	0.08	0.92	0.32	1.09
GP20	0.18	0.14	0.89	0.78	1.32
GP30	0.14	0.21	0.87	1.47	1.66

Figure 3. Accelerated chloride penetration test: (a) AAM samples; (b) Immersed setup.

Figure 4. (a) Normalized heat evolutions of paste mixtures; (b) Normalized peak height and time to reach the reaction peak.

Figure 5. XRD pattern of GGBS/FA paste mixtures with different GP replacement at 28 days.

Figure 6. (a) Thermogravimetry (TG) curves of paste mixtures at 28 days; (b) Differential thermogravimetry (DTG) curves of paste mixtures at 28 days.

Figure 7. (a) The pore size distribution of AAM pastes; (b) Cumulative pore volume of AAM pastes.

Table 4. Chloride leaching results of AAM mortars in different depths to exposure surface (unit: mg/mL).

Depth	GP30		GP20		GP10		Ref
	Cl content	Std Dev^a	Cl content	Std Dev	Cl content	Std Dev	Cl content	Std Dev
1 cm	241.20	0.75	288.04	0.88	286.88	1.68	259.76	1.21
2 cm	13.15	0.27	20.81	0.67	26.06	0.14	32.27	0.35
3 cm	12.36	0.33	16.46	0.36	15.25	0.07	19.94	0.26
4 cm	9.50	0.29	13.10	0.16	12.19	0.31	23.01	0.28
5 cm	8.38	0.11	9.55	0.26	11.36	0.04	10.11	0.03

^a Std Dev: standard deviation.

Figure 8. Chloride penetration of AAMs mortars (a) Ref; (b) GP10; (c) GP20; (d) GP30.

Table 5. Apparent chloride diffusion coefficients of AAMs mortars.

Sample ID	De (×10^-12 m^2/s)	Cs (mass %)	Ci (mass %)	SSE^a
Ref	28.26	0.0512	0	0.000052
GP10	25.42	0.048	0.0001	0.000044
GP20	22.38	0.0465	0.0002	0.000049
GP30	20.36	0.0329	0.0003	0.000032

^a Sum of square errors.

Figure 9. Chloride transport in AAM mortars.