Chloride resistance and improvement of fully recycled cementitious materials with both recycled aggregate and recycled powder

Reusing recycled aggregate (RA) and recycled powder (RP) for fully recycled mortar can effectively reduce the amount of construction and demolition waste. This work studied the chloride transport and resistance improvement of fully recycled mortar incorporating both RA and RP. The results showed that RP had certain nucleation and filler effects. . The addition of RA or RP had an increase in chloride diffusion of mortar. Including RA improved the chloride binding capacity, but mixing RP reduced the chloride binding capacity. At equal waste powder content, recycled paste powder blended mortar owned superior chloride binding capacity to recycled mortar/concrete powder blended mortar. The chloride diffusion of fully recycled mortar with both RA and RP were much higher than that of plain mortar. Mixing various RPs could reduce chloride diffusion of fully recycled mortar, and a significant decrease in chloride diffusion occurred as silica fume or metakaolin was incorporated.

Automated summary

Reusing recycled aggregate (RA) and recycled powder (RP) for fully recycled mortar can effectively reduce construction and demolition waste. This study investigated the chloride transport and resistance improvement of fully recycled mortar incorporating both RA and RP. The results showed that RP had nucleation and filler effects. The addition of RA or RP increased chloride diffusion in mortar. Including RA improved the chloride binding capacity, while mixing RP reduced it. Mixture of various RPs reduced chloride diffusion in fully recycled mortar, with significant decrease seen when adding silica fume or metakaolin.