Low-heat steaming treatment of concrete with polycarboxylate superplasticizers
Recommendations for quantity of polycarboxylate water-reducing admixtures, for the properties of Portland cement as well as the curing regimes is presented in order to reduce the Portland cement amount, to improve the transfer and design strength and durability of prefabricated structures. On the basis of experimental studies the parameters of low-heat steaming treatment of concrete with a polycarboxylate superplasticizer were stated: the duration of pre-exposure 2.5–3 hours, the rate of temperature rise 7°C/hour, the temperature of isothermal exposure 40–50 °C. The results obtained can be used in the production of precast prestressed sub-rail structures as well as other reinforced concrete structures with high performance characteristics at concrete plants with double or single mold turnover per day.