Behaviour of FRP-Confined Rubberised Concrete with Internal Recycled Tyre Steel Fibres

Abstract

This paper examines the use of Fibre Reinforced Polymer (FRP) confinement at enhancing the compressive strength and deformation capacity of Rubberised Concrete (RuC) with high rubber contents. To achieve this, a total of 20 cylinders (100 × 200 mm) are examined and tested in uniaxial compression. 40% of the natural aggregate (coarse and fine) of the RuC mixes was replaced by rubber particles recovered from waste tyres. 18 of these cylinders were externally confined with different layers (0, 2 and 4) of Aramid Fibre Reinforced Polymer (AFRP) sheets. The addition of different dosages (0, 20 and 40 kg/m3) of Recycled Tyre Steel Fibres (RTSF) in some of the unconfined and confined RuC cylinders is also investigated. The results indicate that adding RTSF in the confined RuC specimens enhanced the axial strain by less than 25%, thus being substantially ineffective. However, the use of 40 kg/m3 of RTSF in unconfined RuC enhanced the concrete deformability by 50% over normal plain concrete. This unconfined RuC with RTSF has large deformability, a property that could be utilized to build semi-rigid concrete pavements.