Mechanical properties, corrosion resistance and microstructural analysis of recycled aggregate concrete made with ceramic wall waste and ultrafine ceria

This study examines how incorporating ultrafine cerium dioxide particles (UFCe) into recycled coarse aggregate concrete affects its physical, mechanical, and long-term properties. No analogous research exists about the impact of ultrafine cerium dioxide particles on various characteristics of concrete containing recycled aggregates (RCA). UFCe was employed, and its mean particle size was 350 nm in different doses (0.0, 0.5, 1.0, and 1.5 % by cement weight) to explore its effect on the properties of concrete containing 25 % coarse aggregates (RCA) prepared from ceramic wall waste. The setting time, slump flow, porosity, water absorption, compressive and tensile strengths, electrical resistance, chloride penetration resistance, corrosion resistance, and microstructure analysis were investigated. The findings indicated that UFCe significantly enhanced the compressive and tensile strength while decreasing water absorption and pore ratio comparison to the control mixture after 90 days of curing. Moreover, all mixtures displayed significantly lower chloride penetration depth and corrosion rate than the reference mixture. The inclusion of UFCe additionally improved the microstructure due to the enhancement of the ultrafine particle hydration process. On the other hand, the optimum improvement of mechanical strength, durability properties, and microstructure was recorded at a UFCe replacement rate of 0.5 %. For example, the compressive and tensile strengths increased by 33 % and 9 %, respectively, while the total water absorption and migration coefficient were reduced by 42 % and 67 % at 90 days, respectively, compared with the reference sample.