This research aimed to study the behaviour of concrete after adding recyclable waste materials into the mixture. According to a number of studies and reports widely published on crumb rubber and poly (ethylene terephthalate) (PET) fibre, both materials were of interest for this study. Based on a structured mixing of 7 different proportions of crumb rubber with 2 different proportions of PET fibre, samples of 108 concrete cylinders were collected for testing on compressive strength. Flexibility and ductility were tested on 6 specimens of concrete beams, and the strain contour of 6 reinforced concrete beams of 2 meters length were evaluated. As a result, it was found that concrete with recycled materials had lower compressive strength than conventional concrete. Moreover, the finding in terms of flexibility, energy dissipation, and strain capacity revealed that adding PET fibre and crumb rubber significantly improved the performance of conventional concrete.
