Calculation of the close packing of fine aggregate on the basis of screening for fine grained concrete
The paper considers the calculation of the maximum packing density of fine aggregate. The selection of the granulometric composition of the aggregate is given. The bulk densities and packing densities of standard screening fractions were determined. The content of each fraction in the mixture and the packing density of the aggregate mixture are calculated by the introduction of a subsequent finer fraction. Topological calculation of sandstone screening was performed. The results of sieving of sandstone screening are presented. The high-density grain composition of aggregate for fine-grained concrete is obtained. The compositions of concrete mixtures have been designed. The volume ratio of aggregate and cement paste in the concrete mix, the average mass size of the aggregate grains in the mixture, the volume fractions of cement and water in the concrete mixture are determined. The physicomechanical characteristics of fine-grained concrete of various compositions with a high density aggregate are shown. Results of testing the control samples for compressive strength are given. The density of the obtained samples was determined. Conclusions are drawn on the work.
Keywords: Fine-grained concrete, fine aggregate, granulometry, screenings, sandstone, highdensity aggregate