Method for establishing multiscale prediction model for chloride ion diffusion coefficient of saturated recycled concrete

The invention discloses a method for establishing a multiscale prediction model for the chloride ion diffusion coefficient of saturated recycled concrete. According to the method, the recycled concrete is treated as a cement-based composite material composed of different scale materials, cement paste is hardened at a small scale at first and gradually transited to the recycled concrete at a largescale, and the multiscale prediction model for the chloride ion diffusion coefficient of the saturated recycled concrete is gradually established. According to the method, the influences of differentcompositions of the recycled concrete on diffusion of chloride ions at the nano-scale, fine-scale, microscale and macroscale are considered, according to the multiscale composition of the recycled concrete, the small scale is gradually transited to the large scale, the multiscale prediction models for the chloride ion diffusion coefficients of the hardened cement paste, new mortar and the recycledconcrete are provided in s