The reactivity of SCBA, silica fume, quartz, and different mixtures
of silica fume and quartz was evaluated on the basis of the
variation in the electrical conductivity in a calcium hydroxide solution.
Each test was conducted with 5 g of the sample, the solution
was constantly stirred, and the test temperature was maintained at
80 C. The solution was kept isolated from the environment to
prevent carbonation. The curve showing the SCBA conductivity
variation was corrected to take into account the effect of ions from
the sample in the results following the procedure previously
adopted for a similar residue [15].