Concrete for road paving using fibre and recycled aggregates

Abstract

Wartime requires innovative approaches to the development of materials and structures capable of providing increased reliability, compressive strength, bending strength, as well as impact strength for the protection of critical infrastructure facilities, in particular energy and transport systems. In the laboratory of the Department of Roads and Airfields, experimental studies of concrete are carried out with the aim of creating materials that meet the requirements of modern conditions. During the period of new construction and reconstruction of new buildings, there is a great need for automobile roads. In the study of concrete for highways, we used metal, basalt and polymer fiber, as well as chemical additives. Based on the conducted research, with a number of additives from the Mapei company (superplasticizer, anti-corrosion additive, clogging additive, air-entraining additive, fiber), the following results were obtained: mobility of the concrete mixture in the range from 8 to 18 cm (S-3); air entrainment - from 3 to 4%, which will allow to obtain frost-resistant concrete; compressive strength for 28 days - ≥55 mPa, with water absorption up to 2%. The requirements of regulatory documents allow the use of secondary materials for the concrete of the base of the upper layer of the road surface. That is, crushed structures in fractions: up to 10 mm; 10-20 mm; 20-40 mm. They can be used after laboratory studies, physical and mechanical characteristics and development of recommendations. These results make it possible to create concrete with significantly increased operational characteristics, which are necessary to ensure the reliability of objects in wartime conditions.