Brought to you by
Dr Dilum Fernando
Novel Hybrid Bridge System
Associate Professor, University of Queensland; PhD (Civil), University of Queensland
Traditional bridge construction techniques are expensive and time-consuming. Formwork, a site presence of months or years, and labour-intensive processes all add to the costs for stakeholders.
The materials typically used in bridge construction have a high embodied energy and thus a high impact on the environment.
A University of Queensland (UQ) team led by Dr Dilum Fernando attempted to address these issues by developing a novel double-skin tubular arch (DSTA) bridge system.
The project won the BERD-FEUP Prize for World Innovation in Bridge Engineering.
A DSTA bridge consists of double skin tubular (DST) members, including DST beams, DST columns and DST arches. These hybrid DST members consist of an outer tube made of fibre-reinforced polymer and an inner tube made of steel, with the space in between filled with concrete.
The two tubes can be concentrically located to form a section form more suitable for columns or eccentrically located to form a section form more suitable for beams.
Hybrid DST members can be constructed in-situ or precast, with the two tubes functioning as the stay-in-place form.
Fernando’s award-winning innovation has the potential to complete major bridge works projects that could last years in just three days. The new bridge design can be prefabricated, transported on a semi-trailer and erected without the need for specialised heavy-lifting equipment.
A case study demonstrated that building a railway bridge overpass in Brisbane using this technology would take just 78 hours and save $120 million over the traditional build cost.
A 12.5-m span prototype DSTA bridge was designed and constructed at the UQ structures laboratory. During testing, it showed excellent performance against static and dynamic loading. Advanced numerical modelling approaches, as well as simplified design approaches, were developed to design the systems.
The project won the BERD-FEUP Prize for World Innovation in Bridge Engineering, beating entries from around the world, including from industry giants such as TY Lin and Laing O’Rourke, as well as top universities such as ETH Zurich and the University of California, Berkeley.