We are pleased to say that in 2013, we won a national Australian award for our galvanising work.
As part of the Adelaide Rail Electrification project, a number of commuter rail stations have been upgraded, which included major redevelopments of both the Elizabeth and Munno Para stations along the northern Gawler line.
On the southern line, a 5.7km dual track extension to Seaford required the construction of two major rail stations at Seaford and Seaford Meadows.
An important requirement of the design for these projects was to develop stations which created safe, attractive and welcoming transport infrastructure that is user friendly and comfortable.
Each station required a fully enclosed pedestrian overpass with lift towers and enclosed stairs – all of which were 4 x 4m in cross section, not usually a design which is conducive to hot dip galvanising.
Where was Galvanising Used?
All structural steelwork for the butterfly roof platform canopies, and the fully enclosed pedestrian overpasses, lift towers and enclosed stairs was hot dip galvanised, as well as the ancillary steelwork including sign gantries over the rail tracks, lighting towers, bike sheds and decorative screens.
In what way does Hot Dip Galvanising add value to the project?
A key requirement was for the stations to be attractive and welcoming while complementing the surrounding environment. Hot dip galvanising with its protective patina blends with the surroundings while providing a neutral base to highlight accent painting and signage. The high hardness and durability afforded will significantly reduce the ongoing maintenance costs by resisting attempts at vandalism; a major concern given they are high traffic amenities which provide idle time while waiting for trains.
What challenges were faced?
The fully enclosed pedestrian overpasses, lift towers and enclosed stairs are 4m x 4m in cross section, requiring early intervention to ensure they could be broken down sufficiently to enable hot dip galvanising. Segments were up to 3.6 to 3.8m high, up to 10m in length and weighed up to 5 tonne, thus comprising large double dips. At the height of the fabrication programme, significant numbers of the segments had to be accommodated without impacting on general lead times for the wider customer base.
With both the chords and braces being large section RHS, adequate draining and venting was a major consideration. Not only did this have the potential to impact on galvanising productivity, excessive dip times would significantly compromise quality and potentially result in stress relief and straightness issues. The double pipe columns of the platform canopies also required early consideration of the design, particularly those with the large downpipe spigots, to ensure they could be adequately dipped in terms of size and provision of a quality outcome.
How were these challenges overcome?
The challenges posed by the design of key components were identified with all stakeholders at the earliest opportunity to ensure fabrication detailing was commensurate with achieving a quality result (starting with making sure that all sections and segments could be comfortably dipped).
Once fabrication commenced, Korvest Galvanisers was in constant contact with the fabricators, particularly with respect to the draining and venting of the large RHS frame segments for the pedestrian overpasses, lift towers and access stairs.
Initial concerns over the adequacy of shop repair when welding the segments together were allayed with the assistance of the GAA technical note on this topic.
Describe how Teamwork existed on the project?
The vision of hot dip galvanising for long term corrosion protection and low maintenance costs in a high traffic public space required early collaboration of all stakeholders given the oversize nature of key components with respect to galvanising capacity.
The fabricators actively sought the involvement of Korvest Galvanisers during fabrication and regular contact was maintained to ensure that there were no issues with drainage and venting of the large RHS sections.
This also allowed a clear understanding of the ongoing fabrication schedule, so that the volume of large double dips could be readily accommodated as required without impacting on general market lead times.
These rail stations demonstrate that, particularly with respect to the pedestrian overpasses, lift towers and access stairs, it is not always possible to break components down into single dip sections, but that, if all parties embrace the use of double dipping as a solution, the long term benefits afforded by hot dip galvanising can be realised.
Active promotion of these projects (with the knowledge that the design and fabrication concepts were repeatedly used with great success on four separate rail stations) enhances the potential for hot dip galvanising to actively compete against other systems where previously they may have been considered the only viable corrosion protection option.
Given that structures of this size are generally associated with large scale projects this has the potential to significantly increase the demand for hot dip galvanising. Previously it has been the case that the (assumed) size limit placed on critical components by hot dip galvanising plant capacity has over-ridden the choice of corrosion protection system on the bulk of the project.
With each of the rail stations being highly visible, the potential to increase the promotion of hot dip galvanising is also enhanced.
The Adelaide Rail Electrification project, of which these rail stations are an integral part, is a key initiative by the SA State Government to promote the use of public transport, providing significant environmental benefits.
With a key requirement of the rail station projects being the provision of attractive and welcoming structures to promote patronage, hot dip galvanising provides a vital contribution to the overall project aesthetics.
The major rail station upgrades and developments associated with the Adelaide Rail electrification project successfully demonstrate that oversize components on large scale projects, otherwise considered too big for existing plant capacity, can be hot dip galvanised satisfactorily.
This has the potential to significantly increase the use of hot dip galvanising given that the largest components can often be the limiting factor when considering corrosion protection alternatives.
The design of these modern projects show how galvanising offers a long service free life to constructions designed not just for industrial or mining applications, but for commercial or public locations too.