of composites (materials that are heterogeneous in
their composition). Usually, researchers consider
polystructural composites, i.e. systems composed of
many structures (Selyaev, 1993; 2. Selyaev, 1986).
The mechanical characteristics of fiber
reinforcement are usually much higher than the
mechanical characteristics (Skudra, 1975).
When creating thin-walled structures of transport
structures, composite material from a concrete
matrix and reinforcing elements should be used, as
which either fibers in the form of separate rods, or
fine-mesh grids, or sections of steel fibers are used
(Kurbatov, 1980; Kurbatov, 1980). These randomly
arranged fibers lead to a significant increase in crack
resistance, and also improve the resistance of the
composite to the action of tensile stresses. Quite a
lot of works and publications have been devoted to
the study of various issues of the behavior of fiber-
reinforced concrete, and, as follows from (Nekrasov,
1925), these issues were investigated by Professor
V.P. Nekrasov at the beginning of the XX century.
Over the past three decades, extensive studies
have been conducted on the mechanical
characteristics of concrete, dispersed reinforced with
both steel and synthetic fiber. Professor Stepanova
D.S. (Stepanova, 1975), studying fiber concrete,
determines the dispersion of the fiber filler (the
degree of crushing and dispersal of reinforcement in
the structure) through the ratio between the total
surface of the fiber reinforcement and the volume of
reinforced concrete. And in the work of Tsiskreli
G.D. (Tsiskreli, 1954), dispersion refers to the ratio
between the percentage of fiber reinforcement and
the diameter of fiber reinforcement. Moreover,
despite the differences in the terminology used, it
was concluded that with an increase in the
dispersion index, the work of fiber-reinforced
concrete under tension improves, which delays the
appearance of cracks.
It is possible to note different directions of
research on the work of fiber-reinforced structures:
− study of the adhesion of the filler to concrete
depending on its saturation with fibers, (works
by Kravinskis V.K., Vylegzhanin V.P.
(Vylegzhanin, 1982; Kravinskis, 1979));
− study of structural characteristics of steel fiber
concrete, (works of Kopatsky A.V., Lobanov
I.A. (Lobanov, 1976; Kopatsky, 1979));
− study of the dependence of the parameters of
fiber reinforcement and the properties of the
concrete matrix, as well as the selection of the
optimal composition of the steel-fiber concrete
mixture according to certain parameters
(works by Polyakova L.G., Ovchinnikov I.G.,
Rabinovich F.N. (Ovchinnikov, 1990;
Rabinovich, 1985));
− study of the location of reinforcing fibers on
the properties of fiber-reinforced concrete)
works by Browns Ya.A., Nagevich Yu.M.,
Lagutina G.E., Lavrinev P.G. (Browns, 1986;
Lavrinev, 1983; Rodov, 1980)).
Obviously, this is not a complete list of modern
research directions for such materials and structures
made of them. At the moment, it has been revealed
that the presence of fiber slows down the crack
opening process from 6 to 20 times, depending on
the reinforcement parameters, the loading level
compared to traditional reinforced concrete (with the
same percentage of reinforcement) (Grigoriev, 1983;
Kadysh, 1982; Kurbatov, 1982; Pavlov, 1976;
Varakin, 2020).
This leads to the conclusion about the
effectiveness of using a composite based on a
concrete matrix and steel fiber in the manufacture of
thin-walled structures of transport structures (it is
characteristic that with thick-walled structures, the
advantages of fiber reinforcement are leveled).
In transport construction, flexible pavement has
been widely used for quite a long time, which,
unfortunately, have a short service life in severe
operating conditions. In Russia, many regions are
characterized by a sharply continental climate. It is
characterized by the freezing of soils to a
considerable depth, the presence of permafrost
zones. In this case, rigid structures of pavement
provide long service life. Building structures in the
form of thin-walled plates have become widespread
in various industries. Walls of premises, road
pavement, airfield coverings, regulatory structures
made according to the scheme of rigid plates and
slabs are widely used in modern construction.
In transport construction, plates are used as a
coating on highways with high traffic intensity, with
embankments of poor soils, on urban roads, in areas
where heavy machinery is used, as a coating of
runways at airfields, etc. Road pavement in the form
of plates of fiber-reinforced concrete has a number
of significant advantages compared to flexible
pavement:
− changes in external temperature influences
practically do not affect the stability of
mechanical properties;
−
the use of such coatings provides a longer
service life before major repairs;
− with increasing age of fiber-reinforced
concrete, its strength increases;