The effect of plasticizing admixture on the physical and mechanical properties of concrete with limestone cement

The article analyzes the effect of plasticizing admixture content on the physical and mechanical properties of concrete made of 50 % coarse aggregate. The plasticizer dosage levels proposed by the manufacturer (0.2 % – 1.2 %) were examined and the optimum plasticizer dose (0.8 % – 1.0 %) was established. The use of limestone Portland cement and the optimum content (0.8 % – 1.0 %) of plasticizing admixture in the production of concrete increases the compressive strength, density, frost resistance, whereas the water absorption is reduced. The test results have revealed that plasticizing admixture insufficient or overdosing can reduce the physical-mechanical properties of concrete. With the optimum content of plasticizing admixture durable and frost resistant concrete can be obtained