The mechanical and rheological  properties of concrete depend to a great extent upon the type of realized structure which can be viewed from the aspect of the relationship of the space  between the grains in the aggregate and the quantity of the the cement paste in the concrete. The influence of the degree of filling of the cavities in the aggregate with the paste (k_e) on the consistency type has to view in the light of the realized structure of concrete taking into consideration the particle size distribution and water-cement ratio. Generally, with the increase of the degree of filling of the cavities in the aggregate with the cement paste from 0.9 to 2.5 the consistency of concrete changes from stiff to very fluid. The maximum values of compressive strength are realized when the degree of filling of the cavities in the aggregate that can be considered as optimal is within the relatively narrow limits, and then the value of the parameter ranges between 1.2 to 1.4.