Recycling plastic waste has always been vital for sustainability, besides exploiting that waste to improve the mechanical properties of concrete mixtures which contribute effectively in the field of civil engineering applications. In this research, the enhancement of compressive, tensile and flexural strength of concrete mixtures was explored using both adding plastic fibers and HP-570 super-plasticizer. Plastic waste, as fibers, was mixed with an Ordinary Portland cement for a total volume of concrete of 0.5, 1, 1.5 and 2%, then the HP-570 super-plasticizer was added and the procedure was re-done. At the age of 28 days of curing, the compression strength was increased by (13.2%) while both tensile and flexural strengths were increased significantly by (117.4%) and (207.5%) respectively when using the plastic as fiber with 2%. Further improvement was gained by adding the HP-570 super-plasticizer for the concrete mixture.

Concrete is the most popular construction material and has a relatively high compressive strength and it does not crack under its own weight, but its tensile strength is much lower compared to its compressive strength. The compressive strength can be changed according to the water to cement ratio during concrete formation or mixing, while the tensile strength rises when additives are used, concrete needs reinforcing steel, and added to plain concrete, resulting in reinforced concrete. In other terms, concrete consists of sand or fine aggregate, gravel (which is a coarse aggregate), water, and cement (which is considered a bonding material), and it is a brittle material that needs reinforcement and also some admixtures to improve its low tensile resist. This research aims to increase and improve some mechanical properties of concrete by using waste tiles as coarse aggregate. The study includes replacing normal aggregates with waste tile and using them as crushed aggregate with 25, 50, 75, and 100% replacement. Studies show increment in compressive and tensile strength and flexural strength by using waste tile aggregate compared with ordinary concrete; compressive strength increased from 34.1 MPa for reference mixes without waste tiles to 39.8 MPa using waste tiles. The study included improving all mixes with polycarboxylate superplasticizer and gaining high strength concrete, especially mixes with 50, 75, and 100% waste tile aggregate; the compressive strength with totally waste tile replacement gave the highest value of compressive strength, which was 57.5 MPa, tensile and flexural strength also increased by using waste tile aggregate, and 100% replacement shows optimum values of mechanical properties in this study.