Changes in flexural, tensile and impact characteristics of kerb concrete due to the addition of tyre-derived aggregates and polypropylene fibres

Abstract

Kerb is an integral part of the roadway that provides structural support and facilitates drainage. When constructed over expansive soils, they face additional tensile stresses due to swelling and shrinkage caused by seasonal moisture variations. Tree roots can also exert additional tensile stresses that need to be absorbed by the kerb. Due to the relatively low deformation tolerance of concrete, premature failures are common. This study, a rigorous laboratory investigation, evaluates the effect of adding tyre-derived aggregate (TDA) and recycled polypropylene fibre on tensile strength, deformation tolerance, flexural toughness and impact resistance of concrete for potential use in road kerb construction. The effect of replacing natural coarse aggregates with recycled concrete aggregates has also been investigated. It has shown that TDA can improve deflection tolerance and polypropylene fibres can help resist larger tensile stresses. 5 % rubber with 0.66 % polypropylene fibres could be used as effective solutions in areas prone to expansive soil movement and tree root migrations.