Influence of calcium stearate on the properties of self-consolidating concretes

Moisture and water transfer into concrete can be considered as a major threat to the durability of concrete. Damp-proofing admixtures like calcium stearate (CS) can provide a water repellent layer along the capillary pores. As a result, water and moisture transfer into concrete will be restricted by means of this layer. Accordingly, this research studied the effects of CS on the properties fresh and hardened self-consolidating concrete (SCCs). The evaluation of fresh concrete properties demonstrated that the density of fresh SCCs, passing and filling ability were reduced due to incorporation of CS. Moreover, reduction in density and compressive strength of the hardened concrete can be deemed as the major impacts of CS on mechanical properties of SCCs. In fact, the last-mentioned parameters were decreased by respectively 4% and 30% due to inclusion of 7kg/m3 CS. Furthermore, utilizing CS can not be taken into account as a constructive approach to improve the durability chracteristics under hydrostatic condition. Because no considerable improvement can to be detected in the results of electrical resistivity and rapid chloride migration tests. Eventually, CS drastically enhanced the permeability of the concrete under non-hydrostatic condition. To be more precise, addition of   7kg/m3   of CS decreased the final depth of capillary water absorption, short and long-term water absorption by respectively 60%, 65% and 15%.