Dynamic response of rubberized concrete columns with and without FRP confinement subjected to lateral impact

This study experimentally investigates the impact response of rubberized concrete columns subjected to lateral impact. A pendulum impact testing apparatus was used to test the concrete columns with varied rubber contents including 0%, 15%, and 30%. Fine and coarse aggregates were replaced by crumb rubber with particle sizes of 2-5 mm and 5-7 mm, respectively. The experimental results have shown that the rubberized concrete columns significantly reduce the peak impact force (27%-40%) and thus mitigate the risk of injury and even death if rubberized concrete is used in roadside barriers. In addition, the rubberized concrete columns were more flexible than the normal concrete columns. They could deflect twice the reference columns before failure. Rubberized concrete significantly increased the impact energy absorption. The columns with 15% and 30% crumb rubber showed an increase in the impact energy absorption by 58% and 63% as compared to the reference columns. The rubberized concrete column confined with FRP outperformed the reference columns in terms of both the energy absorption and load carrying capacity. Therefore, rubberized concrete is a better alternative and recommended for the use in roadside barriers to achieve better impact energy absorption capacity and reduce the maximum impact force under vehicle collisions.