Analysis of the mode of squeezing out excess water for mixing concrete mixture in the process of peristaltic compaction

For the formation of a mixture of a given workability of the optimal conditions for the hydration of the binder, it is necessary to use concrete mixtures with a high moisture content. However, in order to optimize the properties of concrete, to obtain ultimate strength, it is necessary to remove excess mixing water. The physical and mechanical properties of concrete will be in direct proportion to the amount of residual mixing water [1, 2]. If the concrete mixture is compacted by squeezing out a certain amount of free water, then the strength of concrete will be in inverse functional dependence on the residual W/C, since it is this that determines the porosity of cement stone and concrete. Therefore, in order to obtain concrete of extremely high strength and density, the pre-laid mixture must be additionally compacted under conditions of maximum concrete dehydration. With complete mold tightness, the mixture is compacted only due to a slight decrease in the volume of entrained air, i.e. the effect of vibro-shock-peristaltic compaction will be insignificant. This effect will increase with an increase in the water permeability of the mold walls, since in the presence of filtration holes, free water under the action of the difference in pressure inside the mold and outside it will begin to move towards the filtration holes [3].