THE MECHANICAL PROPERTIES OF CRUMB RUBBER STEEL FIBER CONCRETE (CRSFC)

Waste materials can be used in concrete as part of replacement material. Currently, 4 billion tires are abandoned in landfills, with 1 billion generated annually and 1.2 billion dumped without treatment by 2030. The number of waste tires is continually increasing, because of the growing use of transport vehicles. Therefore, effectively reusing waste tires as crumb rubber in the mix of concrete can save energy and protect the environment, while the use of steel fiber in the concrete will help enhance its properties. The aim this research to producing the steel fiber crumb rubber concrete (CRSFC) and to balance the issues of strength loss and sustainability. Crumb rubber is used as sand replacement in the mix concrete in the following proportions: 0%, 5%, 10%, 15%, and 20%, while steel fiber is added in the following proportions: 0.5% by volume. Slump, compressive strength, dry density, water absorption, ultrasonic pulse velocity, and rebound hammer tests are performed on the concrete after curing. As the percentage of CRSFC increased, the slump value and dry density decreased while the water absorption increased. Steel fiber helps increase compressive strength by 33 % over normal concrete. The optimum percentage of crumb rubber in CRSFC as a sand replacement is approximately 5% to 10% by volume. In summary, incorporating crumb rubber and steel fibers into concrete can result in a more eco-friendly and resilient construction material.