Modification of conditions and properties of dispersed reinforcing fiber during construction and operation of asphalt concrete pavements

Abstract

Purpose: Identification of deformation presence or absence, fiber destruction in manufacturing asphalt concrete mixes contain ning polymer fiber.Methodology: Initial dispersed reinforcing fiber made of thermoplastic fiber-forming polymer and mineral thread, fiber extracted from asphalt concrete, and fiber exposed to weather conditions are investigated using a weatherometer IP-1-3. Аn MIM-10 metallographic microscope is used for the metallographic analysis. The infrared spectrophotometer SPECORD M-80 is used for the material identification. Physicochemical tests of fiber are carried out in a certified laboratory "Khimvolokno".Research findings: Dispersed reinforcing fiber made of thermoplastic fiber-forming polymers show deformation in compacting the asphalt-concrete mix at impact points of mineral material grains. At the same time, mineral fiber used as a dispersed reinforcement is not subjected to such deformation. The fiber properties are not affected by natural and climatic factors. It is found that natural and climatic factors do not cause the fiber destruction in dispersed reinforcement. The properties of reinforcing fiber slightly change, which allows them to perform a reinforcing function throughout the established service life of asphalt concrete pavements. Indentation of mineral material grains into fiber made of thermoplastic polymers leads to fiber jamming by grains, that prevents them from being pulled out, that, in turn, increases strength and rheological properties of asphalt concrete.Value: The analysis of chemical fiber characteristics is requireв to satisfy the growing interest in dispersed reinforcement of asphalt concrete. The quality of polymer fiber used for reinforcement can be changed under the influence of external factors and affect the quality of road pavements.