Increasing the strength and durability of small-piece products from hyperpressed concrete

The article considers the lack of production of products from hyperpressed concrete. At a high intensity of pressing in concrete, deformations of the elastic aftereffect are manifested. The magnitude of the deformations of the elastic aftereffect at the intensity of pressing 6, 12, 24 MPa is established. Methods have been established to reduce the effect of elastic aftereffect deformation on the strength and durability of hyperpressed concrete. An increase in the structural strength of hyperpressed concrete at the age of 4, 6 and 8 hours with reinforcement with basalt fibers by about 320 % was revealed. The structure of hyperpressed concrete reinforced with basalt fiber was studied. The issue of the complex use of reinforcing fibers and a plasticizing additive in order to prevent destructive processes occurring in hyper-pressed concrete at high pressing intensity is considered. An increase in tensile strength during splitting of hyperpressed concrete by 16 % was established with the combined use of basalt fibers and a plasticizing additive. The durability of hyper-pressed fiber-reinforced concrete was assessed by its frost resistance. A significant decrease in the water absorption of hyperpressed concrete has been established with the combined use of basalt fibers and a plasticizing additive. The absence of the influence of destructive processes during alternate freezing and thawing on the strength of hyper-pressed concrete with a high intensity of pressing with a change in recipe-technological factors was revealed. A material with a frost resistance grade of over FI 400 was obtained.