Alkali-silica reaction in concrete with natural aggregates from northern Poland

Abstract

Quaternary fluvioglacial gravels, used as aggregate in concrete production, were studied. The studies aimed at verifying the thesis, that certain components of concrete are responsible for the decrease in the concrete quality. The test concrete bars were prepared using gravel as aggregate. The bars were investigated by optical microscope and electron microprobe especially at the surface contacts of the potentially reactive mineral substances (chalcedony, opal, tridymite, fine-crystalline quartz), susceptible to alkalis present in the cement. The studies showed the formation of substances typical to those formed from reactions of alkalis with various types of silica; these substances lowered the quality of the concrete.