Aurecon was appointed by steelwork contractor, Alfasi, to provide design engineering services for the long-span curved steel roof of the terminus building – which is approximately 180m long and 30m high with an elegant freeform curved profile.
One of the major challenges that Aurecon faced during the project was the complex interface between the temporary works, the permanent roof and the supporting substructures.
The trusses are supported by only nine groups of slender raking columns. The V-trusses are interconnected transversely by secondary trusses and complex stability systems, working together to form an efficient three-dimensional structure.
Aurecon’s scope of work comprised two major tasks; performing erection engineering of the roof and designing the temporary works. This included assisting Alfasi in developing the erection sequence, assessing transient stresses and movements, determining fabrication geometries, and designing support for the steelwork during all phases of erection.
These analytically demanding tasks were tackled collaboratively by the Aurecon project team in the Sydney, Hong Kong, Bangkok and Brisbane offices, with the innovative use of sophisticated analysis tools.
Several critical juncturesrequired innovation to achieve the desired construction programme. For example, the layout of the temporary towers needed to be adapted by the inclusion of low level truss members to make allowance for the tower cranes and other construction activities that simultaneously occur during erection.
This innovation solved the problem in a cost effective way with minimal impact on the substructure and the temporary works.
Additionally, staged construction analysis of the WKT roof has added significant value for Alfasi. For example, the initial analysis predicted that the erection method originally considered – a strand-jacking erection method – would overstress the truss members. As a result, Aurecon worked closely with Alfasi to develop an improved erection sequence.
Through extensive communication and collaboration between Aurecon, Alfasi and other parties, a suitable solution was successfully designed to achieve our client's vision.