Performance based design of bonded whitetopping overlays

Abstract

This paper proposes a new performance based design method for bonded concrete overlays of existing asphalt pavements. Important input parameters such as the residual bearing capacity of the hot mix asphalt (HMA) layer and its thickness, the temperature-dependent interface bonding properties between the existing HMA and the new concrete layer, the climatic conditions and the traffic loads are being characterised. The implementation of temperature-dependent elastic modulus of the HMA and interface bonding properties in the design model allows for a more realistic determination of the overlay thickness and the design life. Further, a design catalogue was derived based on the results from a number of pavement structure analysis with varying parameters. For a given expected number of heavy goods vehicles (HGV) passes, the thickness of the existing HMA and its residual bearing capacity it is possible to determine the required concrete overlay thickness.