Our award-winning Bridge team delivered the detailed design for 19 bridges and viaducts as part of the $2.6 billion Sydney Gateway project on a heavily constrained brownfield site.

BG&E was engaged by the John Holland Seymour Whyte JV (JHSW JV) to deliver this transformational project. This critical infrastructure includes a new above-ground, toll-free connection from St Peters interchange to Sydney’s international and domestic airports, considerably improving connectivity for surrounding precincts and reducing commuting times.

The scope of our work included a 545 metre long viaduct, bridges with spans up to 100 metres that comprise network arches, steel composite box girders, and continuous Super-T bridges. Airport Drive, a crucial roadway running circumferentially around Sydney International Airport, links the Domestic and International Terminals. BG&E’s selection of a network arch bridge resulted in a minimised and shallow abutment footprint which prevented disruptions of Airport Drive during construction. This Australian-first network arch bridge maximised sustainability targets for the project as the efficient network-hanger geometry resulted in significantly reduced steel tonnage compared to other steel bridge structures.

BG&E further optimised the design by eliminating the transverse bracing, traditionally used to connect the tops of longitudinal arches or trusses, by adopting advanced finite element buckling analysis to Eurocodes. The removal of overhead bracing simplified the construction of the 45 degree skewed bridge deck – providing unlimited overhead clearance for trucks and resulting in a pleasing signature structure to be enjoyed by visitors and Sydney siders alike.

BG&E contributed to the John Holland Seymour Whyte Joint Venture (JHSW JV), which delivered the design and build of the multi billion dollar project.

BG&E Scope

• Detailed design of the 21 bridges (across 13 bridge locations) within a radius of 2.5 kilometres, which is one of the most congested and complex bridge projects in the world.
• Design services for temporary works and durability, particularly when related to complex steel structure construction.
• Geotechnical services, including pile inspections over 400 bored and CFA piles to validate, and assumed ground conditions with actual ground conditions.

Construction of the Sydney Gateway commenced in 2021 and reached completion in 2024.