Experimental study of the salt solution erosing influence on strength of concrete with recycled coarse aggregate

Abstract

There are carried out the experimental study of the loss of the recycled concrete’s strength depending on the recycled coarse aggregate substitution ratio, quantity of the fly ash and age of the concrete through investigation of the concrete’s compressive strength. It is shown that compared with natural gravel, the recycled coarse aggregates accumulate damages at crushing process and have a lot of micro cracks. In addition, the surface of gravel is wrapped in porous adhesive mortar which provides corrosion resistance of concrete deterioration. With the amount of recycled coarse aggregate increasing, the compressive strength of recycled concrete decreases. The addition of fly ash, which creates a compaction effect, helps improve the erosion resistance of recycled concrete. It is shown that positive effect of aging of recycled concrete is significantly higher than negative effect of salt solution erosion, so with time the strength of recycled concrete is increased.