The influence of stone powder origin and superplasticizer type in the drying shrinkage of RPC

Abstract

In the presented study, the combined effect of stone powder from mineral rocks (basic and acidic) and superplasticizers (naphthaleneand polycarboxylate-based) on drying shrinkage processes and moisture loss in Reactive Powder Concrete (RPC) is considered. Due to the peculiarities of the RPC structure, the moisture shrinkage is not restrained by the coarse skeleton and is completely determined by the characteristics of a hardening cement matrix modified with mineral additives. The paper shows that the balance of forces of internal interaction in the solid and liquid phases during the formation of the cement matrix is greatly influenced by stone powder and its origin. It has been established that the shrinkage of the RPCs with NF-based Polyplast SP-1 is higher than with PCB-based Glenium Ace 30. It was also found that shrinkage processes in RPC containing stone powder from granite and quartz sand do not always correspond to the internal moisture loss rate. Perhaps, due to the high strength of the RPC with stone powder from the listed rocks, a resistance to volumetric change increases during moisture loss, which in turn leads to a decrease in shrinkage deformations.