Modeling of chloride diffusion in concrete containing low-calcium fly ash

► A model to predict chloride ingress in fly ash blended concrete is proposed. ► The model consists of a hydration model and a chloride diffusion model. ► The evolution of properties of concrete is obtained from the hydration model. ► The results from the hydration model are used for predicting chloride ingress. ► The proposed model can be used for durability design of marine structures.