Modeling the dependence of the foam concrete structural quality coefficient on the speed and duration of mixing the foam concrete mixture

Abstract

Experimental studies of the technological factors’ influence on the physical and mechanical properties of foam concrete were carried out. Additive Portland cement was used as a binder. Finely ground quartz sand of fractions 0.08-0.16 and 0.16-0.315 mm was used as a filler. Protein foaming agent Arecom-4 was used as a foaming agent. The porization time of the aerated concrete mixture was controlled using a stopwatch, and the rotation speed of the vertical rotor mixer shaft was controlled with a digital photo-tachometer. In the experiments, the following factors were varied: mixture porization time, mixing speed. The main characteristics of foam concrete were determined by testing the prototypes or their fragments according to the methods of the relevant regulatory documents using verified equipment. In the research laboratory of the DSTU, the studies on the influence of the speed and duration of mixing the foam concrete mixture on the density, strength and coefficient of the resulting foam concrete structural quality were carried out. The article presents the experimental dependences of the investigated characteristics on the speed and time of mixing the foam concrete mixture. The parameters of density and strength show a monotonic decline during pore formation, while the structural quality coefficient exhibits its maximum. The behavior of density, strength, coefficient of structural quality can be described in a single model using the parameters that reflect bonds loosening, a general decrease in the number of bonds in the material and the bonds’ change spatial distribution.