INVESTIGATING THE EFFECT OF ADDING PET SCUM ON THE MECHANICAL PROPERTIES AND DURABILITY OF CONCRETE BLOCK PAVEMENT

One of the biggest environmental challenges in metropolitan areas around the world is removing or recycling waste materials. Waste management is an important issue in every country, while the use of plastics is increasing. Obviously, the effectiveness of sustainable development depends largely on the reduction of destructive activities to the environment and today, the use of renewable energies is a hot topic. One of the ways to reduce the degradation of nature is the use of waste in the industry, which is growing in the construction and concrete industry as one of the most widely used building materials. Considering the disadvantages of asphalt pavement such as increased environmental pollution, high costs due to the price of oil, and viscoelasticity of bitumen, block pavements were put forward as an alternative. This paper examines the effect of addition of PET scum on the mechanical properties and durability of concrete pavements in traffic. Concrete paving blocks were produced with 3%, 5%, 10%, 15%, and 20% replacement aggregates with PET. The method of production of concrete paving blocks was in the form of two-layered masonry and the test performed on concrete specimens included VB test, compressive strength, tensile strength, flexural strength, ultrasonic waves, freeze-thaw resistance, and wear resistance. The results showed that by replacing aggregate with plastic up to about 3%, some parameters such as tensile and flexural strength were improved; however, beyond 5%, the mechanical properties decreased gradually. Also, the results showed that the use of plastic in low percentages did not have much effect on the abrasion resistance and the freeze-thaw resistance. This is despite the fact that the velocity of ultrasonic pulse waves did not change significantly at low replacement levels. Also, the results of mechanical tests and durability of concrete paving blocks with 3% plastic aggregates was able to meet all the requirements of the relevant standards.