The Sydney Yard Access Bridge was one of the early and enabling package of works for the Sydney Metro City and Southwest projects – it runs over the New South Wales (NSW) country rail lines and has allowed for construction of the new Central Station.

The bridge crosses five inter-city rail lines that had never been closed under a single possession. During full closure, the main girders and cross girders were installed within the 54 hour possession window.

BG&E provided the detailed design of the Sydney Yard Access Bridge and the associated civil works and drainage design. The access bridge stretches across Regent Street in Surry Hills and is 140 metres long and eight metres wide with complex vertical and horizontal geometry.

Due to the fixed start and end points of the structure and the need to clear the overhead wires while maintaining a maximum grade, our team developed a box girder solution which enabled the grade to be achieved and the structural design to be carried by a two metre deep steel box through- girder solution.

The tracks below meant the location of the piers was highly constrained. Minimum offsets from rail centre lines further restricted their physical location. The final position resulted in skews of 66 degrees to the deck. BG&E recommended a ladder deck system to ensure the cross members of the deck could remain perpendicular to the main girders, which mitigated any issues commonly associated with high skews.