Effect of Impact Load on Concrete Containing Recycled Tire Rubber Aggregate With and Without Fire Exposure

Abstract

Over one billion tires are disposed into the environment each year and this has become a major environmental issue in the globe. Recycling of these waste tire rubbers in concrete has gained attention from researchers all around the world. In this study, the impact resistance of rubberized concrete exposed to fire is investigated experimentally in the laboratory. For that purpose, sixty specimens were made with five different mixes replacing their sand content partially with different percentages of tire rubber by weight ratios of 0% control, 6%, 12%, 18% and 24%. The water/cement ratio was kept constant at 0.393 in all the mixes. In each mix, fifteen concrete specimens with the size of (150 x 150 x 73) mm were prepared to expose to fire. Every three specimens were gradually exposed to fire for four various durations of (0, 15, 30, and 45) minutes. Each specimen was then tested in a drop-weight impact machine by dropping 2240-gr and 4500-gr hammers from heights of 280 mm and 450 mm. The average impact energy of three identical specimens required for the occurrence of the final fracture was calculated. The investigational results are compared with results of control samples. It is found that the impact energy considerably increased with an increase of the rubber replacement. It is, also, noted that any increase in the burning period of specimens results in a reduction of the impact energy and more early crushing of the rubberized concrete.

Investigation on the effect of Polyethylene Terephthalate (PET) fiber and crumb rubber on energy absorption capacity of concrete

“…This explains the effect of crumb rubber and PET fiber on concrete to prevent sudden collapse, as shown in the result of the OPC having a 0.45 mm width for the first crack at the second blow, then failing at the fourth blow with a 1.1 mm width, which means there is no long time between the first crack appearance and when the failure occurred. In contrast, the presence of crumb rubber and PET fiber decreases the width of the first crack and makes it between 0.05 and 0.15 mm because of the ability of rubber particles to prevent the cracks from growing and stopping early full separation of the concrete (Muhammad & Abdul-Kadir, 2020). In addition, the property of PET fiber to bridging cracks, as well as its longest time between the first crack and failure as RU20P, Fig.…”