Parametric modeling of autogenous shrinkage of sodium silicate-activated slag

In this study, a simple modeling scheme was employed to observe the autogenous shrinkage of sodium silicate-activated slag (SSAS)- one of the most widely used alkali-activated materials. The model parameters, including internal relative humidity, saturation degree of pores, capillary pressure, bulk modulus, and hydration degree were experimentally obtained. The mechanism of SSAS shrinkage was explored using the obtained modeling parameters, which may have some physical quantities, and was discussed comparatively with the shrinkage characteristics of OPC. The results indicated that the most important factors influencing the large shrinkage of SSAS were the high capillary pressure and creep-like behavior, which correlated with pore formation, rather than the stiffness of the matrix and the hydrate type.