Bridges

Castlereagh Road is a key transport corridor in Western Sydney which was constrained by the existing rail overbridge at Penrith on the Sydney Trains Main Western Line adjacent to the Great Western Highway. A new bridge spanning 40m across the through lanes of traffic, additional turning lanes and shared user paths was required to increase the capacity of this corridor. Critically the bridge was required to be installed and reopened in a 5-day rail possession during the December 2019 Christmas holidays. Only limited access to the rail corridor prior to the installation dates was provided and minimising impacts on rail and road services was key to the success of the project. To overcome the above challenges an alternative Self-Propelled Modular Transport (SPMT) methodology was developed. This alternative solution was utilised to move the bridge inclusive of the reinforced concrete abutments, superstructure and pre-installed rail fixtures on the bridge deck from an off-line assembly yard to its final position on the pre-installed piled foundation within +/- 2mm tolerance.

Significant engineering and design input was required to inform the construction methodology and to manage deformation and resulting stresses built up during construction, transport and installation. The expected stresses and deflections of the integral bridge structure were assessed against predetermined threshold values from the initial lift and transportation through to final placement in order to develop and operate an SPMT system to safely move the bridge into position. The alternate SPMT methodology allowed the bridge to be constructed outside the rail corridor and eliminated works over live traffic on one of the busiest traffic corridors in Sydney. This change improved the safety of our workforce, the road and rail users and the wider public significantly. The introduction of the Self-Propelled Modular Transport System allowed opening the new Castlereagh Road Rail Bridge ahead of schedule. A detailed discussion of the construction methodology and key engineering and design aspects of the bridge construction, transportation and installation are provided herein.