Effects of Foam Concrete Density on the Mechanical Properties of Foam Concrete

Various research projects have been conducted to study the mechanical properties of foam concrete. They have characterized the microstructure of foam concrete and improved the properties of this material. The following study investigates the effects of specimen density on the mechanical properties of foam concrete.

Foam concrete is a lightweight material with high fluidity and thermal insulation properties. It also has high strength to weight ratio, low permeability, and good fire resistance. It is a low-density material, weighing less than two thousand pounds per cubic foot. It is mainly composed of sand, cement, water, and fly ash. The density of foam concrete is dependent on the amount of these basic ingredients and the mixing regime.

The physical characteristics of M-2, a mixture composition containing fly ash and cement, are shown in Table 8. The strength, compressive strength, and impact toughness of M-2 correlated with strain rate. The ultimate compressive strength and energy absorption capacity increased with density.

The impact toughness of M-2 showed a strong correlation with the peak stress value. The peak stress value increased with increasing strain rate and impact velocity. The dynamic compressive strength was correlated with the strain rate when 10-100 s-1. The relationship between the strain rate and the dynamic ultimate compressive strength was similar to that of traditional concrete.

The structural characteristics of foam concrete were investigated using scanning electron microscopy. Images were obtained using a Quanta 250 FEG (Applied Precision Ltd., Bratislava, Slovakia) operating in low-vacuum mode. This technique provided detailed images of non-conductive specimens without the need for a sputter coating.