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Application of alkali-activated industrial waste 373
Figure 13.9 The effect of SF addition on the compressive strength of one-part geopolymer
binders prepared from alkali thermal activated RM: (A) 10% Na 2 O series; (B) 15% Na 2 O
series (Ye et al., 2016).
cured under different conditions. Reactivity of the GC was good for powders with
2
fineness higher than 2000 cm /g. The 5M-NaOH activated samples showed high
mechanical performance for curing temperatures of 40 and 60 C: 30 50 MPa was
reached after 56 days of curing. For 5M-KOH series, strength development was
similar and 60 MPa was obtained for 56 days and 40 C for powder with
2
4170 cm /g fineness.
Redden and Neithalath (2014) tested the durability of GC geopolymers under
moisture conditions and found that gels formed when GC was the only precursor,
were unstable and a strength loss was observed. The hydrolytic instability was
attributed to decomposition of sodium silicate gel. However, when MK and BFS
