Modern construction practices increasingly recognize the importance of developing alternative methods and materials that can reduce the negative ecological impact of the construction sector. By utilizing recycling processes, the need for the exploitation of natural materials, which are non-renewable resources, is reduced, thereby minimizing waste and contributing to environmental protection. Six students were engaged in the students' internship, conducted with the collaboration of Dzemal Bijedic University of Mostar and Makerspace Garaza. They were introduced to green construction concepts and PET waste recycling.
The experiment is conducted with recycled PET bottles to explore using fibre reinforcement in concrete, which can increase the material's strength and durability. The plastic strips were produced using a filament extruder with widths up to 1 cm. Secondary processing with a PET bottle cutter resulted in fibres with a thickness of 1.8 mm. Since the recommended fibre diameter for concrete mixtures is 0.2 mm, further processing was conducted with a 3D printer to reduce the thickness to the target diameter of 0.2 mm. The final product is the bundle of fibre cut into 3 cm length fibre.
After the production process, the concrete mixtures will be prepared. Besides the reference mixture, the mix with 1% plastic PET fibres and 1% commercial polypropylene fibres was ready. The aim is to compare the concrete reinforcement of plastic PET fibres with commercial fibres. The evaluation will be through fresh concrete properties and hardened concrete properties such as compressive strength, flexural strength, freeze resistance, freeze-thaw and salt resistance, and water impermeability.
