PSI - Issue 81

Orest Polishchuk et al. / Procedia Structural Integrity 81 (2026) 316–320

317

concretes. The most heavily loaded and functionally critical areas of highways, which are subject to intensive traffic impact, include exits from highways, technical stop sections, public transport boarding areas, road junction nodes, intersections, as well as crossings with tram and railway tracks. For pavement construction in these zones, it is advisable to use high-strength concretes with dispersed reinforcement. The choice of reinforcing fiber plays a key role in shaping the performance properties of fiber-reinforced concrete (Lau et al. (2020); Hussain (2020); Małek et al. (2021); Kabashi et al. (2021)) . Different types of fibers possess specific physical and mechanical characteristics that determine the appropriateness of their use in particular structures, taking into account loading conditions, durability, crack resistance, and exposure to aggressive environments. In road construction, the permeability and density of concrete have a decisive influence on its durability, often even greater than the type of cement used. The implementation of efficient technologies and materials makes it possible to address important issues related to the restoration of concrete and reinforced concrete structures (Korniychuck et al. (2024), as well as their production with specified properties (Dovbenko et al. (2024)). The effectiveness of introducing modern and diverse technologies and materials into construction requires comprehensive research (Dvorkin et al. (2021); Surianinov et al. (2022)). Such materials are a family of concrete composites, which can contain dispersed fibers from different materials (steel, polypropylene, basalt, glass, carbon, kevlar, etc.) that form a spatial reinforcing framework across the entire cross-section of the structure (Drobyshynets et al. (2024)). Fiber concretes have high tensile and flexural strength, crack resistance, frost resistance and low abrasion resistance, which is very important for floor structures and road pavements (Pombo et al. (2022)). Since cement is a key component in the production of concrete and reinforced concrete structures, its corrosion resistance largely determines the durability of the structures and materials based on it. The most common forms of chemical aggression affecting concrete structures include cement leaching, the action of sulfates, and exposure to natural waters with a low acid content (Xu et al. (2022); Taheri et al. (2020); Yu et al. (2023); Song et al. (2020)). It is worth noting that in road construction, the permeability and density of concrete have an even greater impact on its durability than the type of cement used. One of the methods of protecting concrete from corrosion is the addition of fiber to the mix. Moreover, modern concrete protection technologies make it possible to enhance the resistance of the cement matrix to destruction even under the influence of multiple adverse environmental factors. The impact of an aggressive environment intensifies when the structures are subjected to loads. When selecting the type and size of fiber, its length should be at least equal to the diameter of the largest coarse aggregate particle. Highways and industrial floors are an integral part of industrial construction. They are critical structures that contribute to the uniform distribution of moving and static loads on the subgrade soils. According to the principle of mechanical operation, they represent a beam on an elastic base. Fiber concrete is widely used to ensure the high-performance characteristics of road pavements and industrial floors. 2. Methodology of experimental studies For the production of samples of all series, fine-grained concrete of class C25/30 was used. Was used as Portland cement CEM II/A-S 42.5 R produced by CRH Ukraine (Volyn Cement PJSC, Ukraine), crushed granite breakstone of a 5 – 10 mm fraction, natural quartz sand of a 0 – 2 mm fraction , the water-reducing admixture MC- PowerFlow т3200 manufactured by MC -Bauchemie, Bottrop, Germany, steel hooked-end fibers (SFs) produced by Stalkanat-Silur, Ukraine, and polypropylene fibers (PFs) produced by PoliArm Ukraine. Polypropylene fiber was used for the second series, while combined polypropylene and steel fibers were used for the third series (Fig. 1). The cubes and prisms of all three series were cast in horizontal metal cassette molds. The formation of the samples for all three series was carried out under laboratory conditions. After 5 days, the concrete reached its initial strength. The formwork was then removed, and the samples were demolded. Further curing was carried out in a humid environment: the samples were covered with fabric and kept moist for 14 days. After that, the samples were stored under normal temperature and humidity conditions in the laboratory (Fig. 2). The corrosion resistance of fiber-reinforced concrete was determined using cubic specimens mea suring 10 × 10 × 10 cm by assessing the change in their compressive strength after 28 days of curing under normal conditions and subsequent exposure to an aggressive environment: acid environment (pH = 3), which was obtained by mixing sulfuric acid and distilled water , alkaline environment (pH = 13) which was obtained by mixing sodium hydroxide and distilled water, kerosene - water – kerosene mixture (pH = 5) which was obtained by mixing kerosene and distilled water. The pH was determined using indicator strips. The Nomenclature CEM I CEM III/A-S 42.5 N CEM ІІ CEM II/A-S 42.5 N with slag SP superplasticizer (air-entraining agent) PFs polypropylene fiber SFs steel fiber