Assesment of strength in concretes substituted with scraped asphalt pavement for coarse aggregate

Reusing damaged asphalt pavement that is removed during maintenance-repair and renewal of deteriorated roadways helps to reduce the need for natural materials and to preserve natural aggregate resources and the environment. This study aims to promote recycling and using of scraped paving materials gained during renewal of asphalt roadways in field concrete and thus contribute to cut down natural aggregate usage. In this dissertation, substitutability of scraped asphalt materials for coarse aggregate in concrete is studied and the behaviors of field concretes substituted with various proportions of scraped asphalt materials under different temperature conditions are investigated. The size of scraped asphalt materials used in experiments was 4–22.4 mm and they were substituted for coarse aggregate in 5%, 10%, 20% and 30% proportions. CEM II 42.5 R Portland cement was used for concrete mix and cement dosage was 350 kg/m3. Experiments were carried out on concrete samples substituted with scraped asphalt materials in rates of 5%, 10%, 20% and 30% for coarse aggregate under both damaged and undamaged conditions. For fresh concrete, slump values and weight per unit of volume were calculated; for samples that were hardened and oven-dried at various temperatures, weight per unit of volume, ultrasonic pulse velocity, pressure strength and bending strength values were calculated and finally values of modulus of elasticity were found for both.