Design and Construction of Seamless Pavement on Westlink M7, Sydney, Australia

Abstract

In contemporary practice continuously reinforced concrete pavements (CRCP) are terminated and anchored at each bridge approach. An approach slab, jointed at each end, provides the CRCP to bridge abutment link. This transition is not always smooth as the provision of transverse joints can lead to discontinuities in the carriageway profile, particularly if the approach embankment settles. The seamless pavement is an enhancement that eliminates transverse joints and provides a reinforced concrete connection between the CRCP and the bridge deck. This results in improved ride quality for highway users and reduced maintenance costs. Additionally, it eliminates the need for pavement anchors behind each abutment, thereby reducing the pavement cost and minimizing construction activities in an area that is generally on the critical path. The seamless connection between CRCP and bridge deck must accommodate the stresses induced by shrinkage, creep, thermal strain, embankment settlement and traffic loads. Numerical models developed to analyse these parameters compare well with the results of post construction monitoring. This correlation has confirmed the validity of initial design assumptions and has, through further development, resulted in a simplified construction method for the closure pour.