When our member The Fletcher Construction Company invited the Auckland branch of Engineering New Zealand to take a peek behind the scenes of The New Zealand International Convention Center (NZICC) and Hobson Street Hotel construction, I jumped at the opportunity.
And believe me when I say, the tour didn’t disappoint – showing many of our members in action!
Setting new records, NZICC uses 8500 tonnes of structural steelwork to create over 32,500 square meters of building space. Steel work counts for over half the material to make it the dominant backbone of the structure with close to 5000 tonnes installed.
In 2015, The Fletcher Construction Company won this massive $477 million construction contract, which also included the Hobson Street Hotel. Following strong tender competition between local, overseas and combinations of both; CH Steel was selected to deliver steelworks – a joint venture between our member Whangarei based Culham Engineering and American owned, Thailand-based Herrick Corporation. With the Hobson Street Hotel upper floor steel work awarded to another of our members – Manukau based Grayson Engineering.
The decision making of Fletcher for fabrication saw a new business model emerge for the New Zealand steel construction procurement landscape. And naturally, created considerable debate and disappointment compared to a fully locally manufactured option. However, looking beyond this contentious start – congratulations must be given to the involved teams for the technical feats achieved so far, especially our involved members.
Flexible design mixed with a uniquely Kiwi feel
Using a very flexible design concept the architects created a multi-purpose facility – five times bigger than the current largest convention centre in New Zealand. Capable of hosting around 4,000 people and providing over 1,300 car parks, its transparent, open design features high ceilings, panoramic views and dynamic spaces.
Its design challenges were no doubt best met with steel construction.
It was also great to see that the building façade and interior art boasted undertones of New Zealand’s identity – a move that should strike a chord with future visitors and users of the space.
Managing logistical challenges
Located in the heart of Auckland City next to extremely busy roads with traffic flow, noise and transmission beam restrictions – it’s not hard to see that there have been many barriers that have needed to be overcome for this project.
Careful planning was required to achieve site access for heavy cranes, and the availability of them in a constrained building market added to the task. This was demonstrated with typical twin crane heavy steel construction work lifts of 50 tonnes – with the heaviest 150 tonnes lift for the assembled walkway over Hobson Street still to come!
Structural engineering challenges
This structure is built strong. Its largest steel columns spanning the exhibition floor level capable of carrying loads over 3500 tonnes each – the equivalent of stopping the Saturn V moon rocket from launching!
Maximum plate thickness of 100mm, provided a formidable welding challenge and QA task. With local fabrication done to (AS/NZS) ISO 3834 – the welding fabrication QA system now commonly used as part of the SFC scheme. Although bolting on site is the dominant structural joint connection method, some complex full penetration site welding has been required which has been subjected to stringent third party inspection.
The heavy plate thickness has also posed challenges in getting the high loads across the connections. And to our knowledge, Grade 10.9 Tension Control Bolt (TCB) bolts were used for the first time in New Zealand to overcome this. Commonly used in Europe and the US – site feedback has provided confidence in the connection quality assurance process going forward.
Steel work tolerances to match are incredibly tight. Especially for some horizontal braces where +/- 1mm and for large pinned Buckling Restraint Braces (BRB) where +/- 4mm is expected.
The BRB’s used were also individually designed and fabricated in the US, requiring performance testing that could only be done overseas. The forward planning and logistics effort required were huge.
Health, safety and environment worker welfare
While the site currently employs ‘only’ 500 employees it shortly will swell to 1,300 with the installation of services – a new aspect that will need careful environmental awareness and management.
H&S was evident everywhere including our own induction with strict PPE requirements. It was also great to see thought was given to the lunch and rest facilities for workers set up in one of the lower car park floors to provide shelter from noise, dust and the weather. Of particular note, were the H&S messages on the underside of the four cranes – showing that Fletcher Construction Company is demonstrating their safety message to everyone.
A well organised site
No doubt, the takeaway impression on the tour was that the site is run professionally for both the convention centre and the Hobson Street Hotel.
Like many projects – start up delays have put the crews in catch up mode, but it’s been indicated they’re on track to finish as scheduled and that the business model of mixing imports with local steel fabrication is delivering the required steelwork to specification and on time.
Seeing the International Institute of Welding (IIW) AS/NZS/ISO 3834 based welding fabrication certification system at work in such a massive local industry led project demonstrates international best practice being used.
Achieving this through our HERA Certification Ltd for certification of the local fabricators and international certification of the overseas’ contribution via IIW partners.
Strong expertise overcomes challenges
The NZICC tour amidst its steel construction phase not only highlighted the immense challenges faced by one of the largest building projects, but how structural steel and a team of dedicated people has successfully handled them.
Should another visit be organised, I’d make sure you’re part of it – it’s well worth your time! Special thanks must also be given to our guides Barnabas Ilko from Fletcher, Richard Archbold from Warren and Mahoney Architects and Richard Built from Beca for delivering the two fully booked tours. As well as to the Engineering NZ and Young Engineers Auckland branches who’ve organised this for the second time as part of ‘Celebrating Branch Centennial’ with the assistance of Branch Administrator Natalie.