Observations on Rubberized Concrete Behavior

As a possible solution to the problem of scrap-tire disposal, an experimental study was conducted to examine the potential use of tire chips and crumb rubber as aggregate substitutes in portland-cement concrete mixes. In this study, strength, durability, and toughness as well as workability, unit weight, and volume change were examined. Rubberized concrete was found to possess acceptable workability and a smaller unit weight than plain concrete. Volume change of rubberized concrete specimens containing 38, 25, and 19-mm rubber aggregates was found to be larger than that of plain concrete. Rubberized concrete specimens exhibited lower compressive and splitting-tensile strength than did plain concrete specimens. However, rubberized concrete did not demonstrate a brittle failure, but rather a ductile, plastic failure, and had the ability to absorb a large amount of plastic energy under compressive and tensile loads. A mathematical model is used to describe quantitatively the effects of rubber aggregates on the compressive and splitting-tensile strength reduction of concrete.