Effect of foam temperature on foam stability of foamed concrete and stabilization mechanisms

In this study, a novel method for increasing foam stability based on adjusting the temperature of surfactant solution used to prepare foam (foam temperature) is presented. The effect of foam temperature on the compressive strength, and stability of the foamed concrete was studied. Meanwhile, laser displacement sensors, X-ray computed tomography, automated surface tensiometer, and electron microscopy were adopted to explore the action mechanisms. Experimental results reveal that the method of adjusting the proper foam temperature can decrease the surface tension of surfactant, reduce the diameters of bubbles, and retard bubble coarsening, thus enhancing the foam stability. The fresh foamed concrete with a foam temperature at 20 °C displays the highest stability level. The foamed concrete with a foam temperature at 20 °C possesses a more uniform pore structure, which explains the reasons for the better properties of foamed concrete.