Mechanical and thermal properties of lightweight concretes with vermiculite and EPS using air-entraining agent

• We compare mechanical properties of lightweight concrete with vermiculite and EPS.
• Lower amount of lightweight aggregate and air-entraining provides higher strength.
• Vermiculite lightweight concrete has lower thermal conductivity than with EPS.
• EPS lightweight concrete has higher strength and is lighter than with vermiculite.

This study aimed to compare mechanical and thermal properties of lightweight aggregate concrete with two kinds of lightweight aggregates, vermiculite and Expanded Polystyrene (EPS) and using air-entraining agent and superplasticizer admixture. For better reliability, a statistical analysis of the results compressive strength and density was used. The factors of the 22 full factorial design were: amount of lightweight aggregate (55% and 65%) and quantity of air-entraining agent (0.5% and 1.0%). The results showed that the addition of air-entraining agent left the lightweight concretes even lighter, but less resistant. EPS lightweight concrete has higher strength and is lighter than with vermiculite. Vermiculite lightweight concrete had lower thermal conductivity than with EPS. The better lightweight aggregate content was 55%.