INFLUENCE OF MODIFIERS AND POLYMER FIBER ON THE STRENGTH OF CONCRETE OF RIGID PAVEMENTS

Abstract

he paper presents the results of comprehensive experimental research aimed at developing modified fiber concretes for use in rigid cement concrete road pavements. The main objective of the study was to investigate the effect of polymer fibers and a combination of chemical additives, including superplasticizer, air-entraining and colmatation additives, on the basic physical and mechanical properties of fiber concrete. The research methodology was based on experimental-statistical modeling using a symmetric four-factor model of experiments to systematically evaluate the influence and interaction of the selected components.

The obtained data indicate that the inclusion of polymer fiber in the amount of up to 3 kg/m³ contributes to a significant increase in tensile strength in bending, reaching values up to 11.0 MPa, while having an insignificant effect on compressive strength. As a result of experimental studies, the optimal compositions of concrete mixtures were determined, providing an average density in the range of 2.3-2.4 g/cm³, water absorption of no more than 1.7% and compressive strength of more than 55 MPa. These parameters meet and exceed the requirements for high-strength road concretes.

According to the experimental results, the developed modified fiber concretes can be recommended for use in the construction of road pavements of I and II categories, where increased mechanical characteristics and durability are important. The frost resistance and durability are planned for further study.