A new mesoscopic calculation model of chloride ion erosion in recycled coarse aggregate concrete (RAC): Characteristic fractal dimension of pore structure and service life prediction

This research investigates the influence of water-cement ratio and recycled aggregate content on the chlorine erosion resistance of RAC by conducting a combination of experimental and theoretical analysis. In addition, a mathematical equation is developed to represent the chloride ion transport mechanism in RAC, taking into account fluid mechanics, energy conservation, and pore structure evolution characteristics. Furthermore, mathematical analysis and modeling are used to forecast the life of the chloride ion erosion process. The results show that both the recycled coarse aggregate replacement rate and the water-cement ratio adversely affect the chloride erosion resistance of RAC. The chloride diffusion coefficient model based on pore structure characteristic parameters exhibits high prediction accuracy. This model helps increase the use of recycled aggregates and fosters the growth of the circular economy in the construction industry sector by offering a theoretical foundation for evaluating and maintaining the durability of RAC.