The quantification of the amount of calcium hydroxide present in the cement pastes with different silica fume contents is more efficient through the mass loss analysis via TGA. Fig. 9 shows the TGA results for the different samples. It is observed a pronounced reduction in the amount of calcium hydroxide for replacements of up to 10% cement with the silica fume relative to the sample without replacement. For replacement contents greater than 10%, a reduction is also observed in the calcium hydroxide mass but at lower rates, suggesting a saturation amount in this phase. The mass loss in the samples with 20% replacement by quartz and by SCBA are also shown for comparison. It is observed that quartz has very low effect on reducing the amount of Ca(OH)2 formation. Most of the effect can be attributed to the lower cement content that will lead to lower hydratatio byproduct instead of pozzolanic activity. However, it is observed that the amount of calcium hydroxide in the sample with 20% SCBA is lower than the amount observed in the sample with replacement by quartz and higher than the sample with only 10% replacement by silica fume. This confirms that SCBA has slight more pozzolanic activity than pure quartz but significantly less than silica fume.