Research on the early age mechanical properties of concrete based on hydration kinetics

Abstract. In the era of advanced construction techniques, the enhancement and regulation of the functionality of concrete, a widely utilized construction material, has gained significant prominence. The study delves into the exploration of the properties and heat reaction behavior during hydration of various composite cementitious materials with the incorporation of three distinct mineral additives: microspheres, cellulose, and early strength shrinkage reducing agent for early strength enhancement. Analyzing the impact of cement hydration reactions on the early-age performance of concrete, the Krstulovic-Dabic hydration kinetics model was utilized to simulate and study the hydration process of the composite cementitious system in concrete. The findings reveal that the introduction of microspheres and cellulose hinders the advancement of early-age strength in concrete, whereas the utilization of an early strength shrinkage reducing agent proves to be beneficial in enhancing early-age strength. Enhancing the hydration reaction rate is observed with the addition of early strength shrinkage reducing agent, whereas the presence of microspheres and cellulose slows down this process. The rate of hydration reaction accelerates, resulting in a greater early-age strength of the concrete.