Assessment of Mechanical Properties and Durability of Concrete Pavement Made with Recycled Concrete Aggregate and Recycled Waste PET

In this research, the mechanical properties of concrete in the conditions of using natural aggregates and comparing the results with the replacement of recycled aggregates with values of 10, 20, 30 and 40% have been investigated. In the first part of the study, the results showed that the specific gravity of concrete in the presence of 40% of recycled sand and gravel was 1.02% and 2.38%, respectively. Also, in terms of compressive strength, the lowest decrease in compressive strength occurred in 10% of recycled sand and the highest decrease in compressive strength occurred in 40% of recycled sand. Then, the mechanical properties of ordinary concrete with concrete containing waste plastic (PET) were compared with 2, 4, 6, 8 and 10% of concrete volume. In this regard, the results of the study indicate a decrease in compressive strength of concrete compared to control concrete. In this regard, the lowest reduction in compressive strength was 2.01% in the presence of 2% waste plastic (PET) and the highest reduction in compressive strength was 16.39% in the presence of 10% waste plastic (PET). Regarding flexural strength, the results showed an increase in flexural strength; So that the lowest increase in flexural strength of 6.27% occurred in the presence of 2% waste plastic (PET) and the highest increase in flexural strength of 39.49% occurred in the presence of 10% waste plastic (PET). In the end, the results showed that increasing the presence of waste plastic (PET) has led to a decrease in water absorption of samples. In this regard, the lowest decrease in water absorption by 5.26% and the highest decrease in water absorption by 23.08% occurred in the presence of 2 and 10% waste plastic (PET), respectively.