Effect of using ground waste tire rubber as fine aggregate on the behaviour of concrete mixes

The development of environmentally accepted methods of used tire disposal is one of the greatest challenges that waste management experts face today. Using of wastes and by-products as concrete aggregate has attained great potential in the last few tears. The aim of this work is to investigate the possibility of the usage of ground waste tire rubber (GWTR) in the civil construction as a partial replacement for fine aggregates and the influence of these wastes on the properties of ordinary concrete. The cement content for concrete mixes is 300, 400 and 500 kg/m(3). The total fine aggregate (TFA) in all mixes is sand., which is partiallyreplaced by GWTR particles. The percentages by volume of GWTR/TFA are 5\%, 10\%, 15\% and 20\%. The physical and mechanical properties of rubberized concrete are compared with those of ordinary concrete mixes. Also, three treated materials, polyvinyl acetate, silica fume and sodium hydroxide (PVA, SF and NaOH) are used for treatment the ground waste tire rubber to improve the interface friction between rubber particles and cement matrix. The results show that the mass density (bulk density) of hardened rubberized concrete decreases with increasing rubber content, this is an advantage for that concrete application. Also concrete specimens containing rubber particles are much tougher than those without rubber particles. The damping ratio of the rubberized concrete containing 20\% rubber is much higher than those of normal concrete by 63.2\%. Rubberized concrete incorporating treated rubber particles gives better results than concrete incorporating normal rubber.