Experimental Study on Mechanical and Thermal Behavior of Foamed Concrete

Abstract

Foamed concrete possesses characteristics such as high strength-to-weight ratio and low density. Foamed concrete reduces dead loads on the structure,saves energy and lowers the labour cost during construction. Foam concrete consists of cement, fly ash, water and air voids. The foaming agent used to generate foam is sodium lauryl ether sulphate. Foam concrete can have 10% to 70% air, which results in a material that is light-weight but may compromise the compressive strength and durability properties. Although it has been shown in the research that less connected air voids yield a lower reduction in compressive strength, with the increase in air voids the thermal resistance in increased. The properties like compressive strength and thermal resistance are studied. Six batches of Foamed concrete were prepared with varying air content 15%, 17%, and 20%. The foamed concrete cube and slab are used for compression and thermal testing. The dry density of foamed concrete varies from 860 kg/m3 to 1245 kg/m3, and the compressive strength varies from 2.5 - 6.5 MPa. In this research, the Dry density, compressive strength and thermal conductivity of foamed concrete is compared with the clay bricks. If foamed concrete blocks are used instead of clay bricks, almost 50% of the dead load of the building can be reduced. The thermal conductivity of foamed concrete varies from 0.021 - 0.035 W/mK. Key outcomes revealed that foamed concrete has good potential to be used for lightweight structural applications for low-rise buildings owing to its evolution of mechanical properties, transport properties and thermal resistance.