Abrasion Resistance Improvement of Recycled Aggregate Pervious Concrete with Granulated Blast Furnace Slag and Copper Slag

The poor abrasion resistance of recycled aggregate pervious concrete (RAPC) limits its application. Granulated blast furnace slag (GBFS) and copper slag (CS) were used as mineral admixtures to replace cement in RAPC for improving the abrasion resistance. At the 10% GBFS replacement level, 5% to 25% of CS was added in RAPC respectively, which reduced the consumption of the cement. The effects of GBFS and CS on paste fluidity, porosity, permeability, compressive strength and abrasion resistance were evaluated. RAPC exhibited an excellent abrasion resistance after adding GBFS and CS. In this case, 10% blended amount was the optimal amount of GBFS and CS. Compared with the single cement group, the abrasion resistance increased by 38.78%, which is mainly because the fayalite in CS supplies good abrasion resistance, whereas the GBFS also plays an important role. The mechanism was studied via X-ray diffraction analysis and microhardness. The porosity and permeability of the RAPC increased with the CS replacement level. Moreover, the leaching concentration of heavy metal ions in the prepared RAPC was significantly low, indicating that RAPC could be applied safely. The results not only provides a feasible technical means for the large-scale utilisation of CS but also presents a theoretical basis for the improvement of RAPC abrasion resistance.