Study on the Model Construction for Predicting the Expansion Behavior of Concrete Using Expansive Additives (Part 2) : A Simulation Model for Expansion of Hardened Cement Paste Taking Into Account Particle Size Distribution

In this study, we constructed an expansion strain calculation model of hardened cement paste (CP) mixed with expansive additives (EA). First, the reaction rate of EA was determined based on previous research results and stoichiometry. And then the expansion strain and restrained stress were calculated using a rule of mixture model. As a result, the stress in the CP was much higher than the tensile strength. This suggests that the apparent elastic modulus of CP is very small at the very early age. Furthermore, the effect of particle size on the expansion strain was analytically clarified.