ABSTRACT
Abstract The compensation effects for autogenous shrinkage of two types of high-fluidity mortar containing different binders prepared by adding with two types of expansive additives at various additive content were experimentally studied. The results indicated that any expansive additive has the compensation effect for autogenous shrinkage, especially a free-lime rich calcium sulfoaluminate based-expansive additive has larger compensation effect for autogenous shrinkage than conventional calcium sulfoaluminate based-expansive additives, and that the effect of the mortar prepared with the same additive content of the expansive additive on the expanded volume varies according to the type of binder. Keywords: Autogenous shrinkage, Expansive additive, High-fluidity mortar
1. Introduction
Since high-fluidity concrete prepared using a high-performance AE water-reducing agent and a segregation-controlling agent (thickening agent) has very high fluidity without segregation of the components, the workability of concrete can be remarkably improved. Such a type of concrete as this is generally prepared at so low water/binder ratio that the powder contents are high. The autogenous shrinkage is, therefore, increased[l].
