Inhibitive effectiveness study of pozzolanic materials on natural aggregates alkali-silica reactivity

In the hydropower project development and construction in Xizang, China, close attention must be paid to testing for potential alkali-silica reactive activity of aggregates and the effectiveness of inhibition measures.Taking natural volcanic materials and natural sand-gravel aggregates from Xizang as research subjects, this study investigated the influence of pozzolanic materials on the alkali-silica reaction expansion rate of natural sand-gravel aggregates using the petrographic method and mortar bar rapid test.The effectiveness of three cementitious system inhibition measures, single-doped fly ash, single-doped pozzolanic materials, and composite-doped fly ash-pozzolanic materials were comparatively analyzed.The results showed that the inhibitory effect of fly ash on the alkali-silica reactive activity of these aggregates outperforms that of pozzolanic materials.Furthermore, the novel composite admixture formed by blending fly ash and pozzolanic materials exhibits adjustable inhibitory efficacy against alkali-silica reactivity, which varies with the mass percentage ratio of the two components.