Centrifuge modelling of ultra-thin High Strength Steel Fibre Reinforced Concrete Pavements

Ultra-Thin Continuously Reinforced Concrete Pavements (UTCRCP) is an innovative pavement type that consists of a 50 mm High Strength Steel Fibre Reinforced Concrete (HS-SFRC) layer overlain on a pavement substructure. The thickness results in a flexural stiffness significantly smaller than for conventional concrete pavements. In this paper, the conceptual understanding of the response of UTCRCP to traffic loading was investigated using centrifuge modelling. Simplified pavement models were subjected to a bidirectional moving axle load. The results indicated that axle loading, and not single wheel loading, should be used to investigate the response of UTCRCP as there is significant interaction in substructure deformation caused by the wheels on the ends of an axle. Due to the flexural toughness of the highly reinforced concrete layer, a gap forms between the ultra-thin HS-SFCR overlay and its substructure. Brittle, cemented bases between the HS-SFRC overlay and subgrade should be used with caution, as the flexible nature of the layers above and below the stabilized layer may result in rapid degeneration of the brittle layer.