Effect of metakaolin particle size on the inhibition of alkali-silica reaction

In this paper the influence of particle size distri¬bution of metakaolin on its ability to prevent the reaction between the cement alkali and silica filler is investigated. Following the procedure of ac¬celerated tests the linear strains in the samples of fine-grained concrete were measured when part of the aggregate was replaced with 5, 10 and 15% of metakaolin from different manufacturers. It was established that the substitution of fine aggregate with only 5% of metakaolin, over 90% whereof consisted of particles under 15 μm in size, resulted in a 42 per cent lower expansion strain; but when coarser metakaolin was used, with 90% of the particles under 40 μm in size, these deformations were reduced by 23% only.

Author: Yu.A. Sorvacheva, T.M. Petrova

Section: Concrete

Keywords: alkali-silica reaction, metakaolin, particle size distribution