To achieve the tall slender structural design of the 12 storey building required the ingenious use of over 700 tonnes of steel. As planned, once it made it to the crucial bracing third level the building process literally took off. Temporary steel bracing structures and ultra smart sequencing of floor construction turned design and time challenges into an exacting art.

Scott Delacy of George Grant Engineering and John Abercrombie of Hawkins Construction discussed the special features of this project, and the inventive solutions.  The biggest challenge was getting it to level three from where clever bracing and erection methodology enabled the rest of the construction to take off at speed.

“ The pressure was on to level three. From there there’s been a floor going up each week. Together, as a team, we nailed every challenge,” said Delacy.

The whole hotel structure, steel frame and comflor metal decking, is 80% steel – and a central core of concrete walls provides the main lateral load resistance. Due to issues with getting the concrete walls out of the ground, and the need to keep the structure progressing, additional temporary steel bracing was put in to stabilise the floor structure until the concrete walls could catch up.  So the steel rocketed up leaving a whole in the middle of the building till the concrete wall could be poured. This had to be very tightly managed.

The in-situ concrete core was done with a large Peri formwork system. (A versatile system with few components that met the demands of the job in a very simple way.) Normally the central walls would have been poured with the rest of the floor structure built off that to provide stability – but to meet all the requirements of the design this proved to be a fast and ingenious solution. This could not have been achieved, as Abercombie described, without “smart programming and great teamwork.”

A second issue for smart programming was the special welding required for the stunning building façade. The large diagonal “V” columns that zig zag from the ground floor to level 3 are impressive, making it a very striking building.

The big “V” CHS columns required tricky configuration to achieve their dramatic sculpted form.  Here composite beams, 100% x ray tested for compliance were used.  Decorative glass fibre reinforced concrete panels adorn the diagonal high strength CHS columns from ground to Level 3 and the north and south elevations.

“ This Novotel Hotel is a one off design – and part of building every building is to look at the plans, understand the engineer’s idea, and push your expertise to find the best way to make it work,” said Delacy.

Finding appropriate weld procedures specific to each application is part of that. For example, the two end concrete walls were joined by steel coupling beams that had to be welded together on site – working on very tight tolerances.

Currently the project is right on target for completion in April 2011. Structural steelwork and internal in-situ concrete core is up to Level 9, and poured to level 6.  Pre cast panels and curtain walling to the façade have commenced.  Floor pours are on a ten-day cycle, and internal cores every 6 days.

The outcome will be a brilliant 4 Star Plus hotel right in the airport terminal precinct – just what the tourism industry has needed for a long time. A building whose design (natural materials, façade transparency, and inspiring form) reflects the essential qualities of New Zealand’s heritage.

The elegant and contemporary Novotel will have 263 rooms, a gymnasium, a 150-seat restaurant and bar, 11 meeting rooms, a conference/function room for 300 people and an airline crew lounge.

The doors will be open right in time for the Rugby World Cup next year.

New Caledonia is a small country with a population of about 250,000. With the construction of 2 other major industrial projects underway at the time, fabrication capacity in the country was limited. Thus fabricating in New Zealand was economical and did not tread on the toes of New Caledonian industries.

The project’s success shows the calibre of New Zealand steel design and construction professionals who were able to design, procure, fabricate, paint and ship all the steelwork for a project overseas with exacting results – despite a very condensed time frame.  Ultimately it shows what can be achieved with real collaboration, strenuous effort and a positive attitude.

Steel was used for two clean up projects at the smelter as part of meeting new environmental emissions standards. The Shaker and Bessemer processes in the SLN Smelter produce harmful fumes and particulates. These had to be captured and “clean” air vented to the atmosphere.

Approximately 300 tonnes of ducting manufactured from Cor-ten plate steel, and 250 tonnes of structural steel for the towers and trestles to support them were shipped to Nouméa. The circular ducts, ranging from 800m to 1200m in diameter were designed to capture and transport dirty gases to a gas cleaning facility. The towers and trestles that support them are between 10m and 20m high.

Beca carried out the process, mechanical and civil/structural design, procured the equipment and steel, and was the direct New Zealand interface for the projects dealings with SLN.

“ Everything was precision designed. Even down to all material being able to fit inside standard shipping containers.” said Gareth Hancock, consultant at Beca, Auckland.

For Beca, the biggest challenge in the design of the ducts was the varying temperatures during the process cycles with gas temperatures up to 600 degrees celsius. This was overcome by incorporating expansion joints at various points and carrying out detailed stress analysis of the ducts. All structures and ducts had to withstand cyclone wind forces and were designed to New Caledonian regulations and French codes.

Economics both in time and cost made steel the structural support choice. Grade 300 steel was used for the critical strength and deformation required. “Cor-ten” steel was used for the elevated ducts due to the potential high temperatures of the gases.  The chemical composition of Cor-Ten steel provides high resistance to atmospheric corrosion.

Grayson Engineering was chosen for the projects as a fabricator highly experienced in both ducting work and structural steel. There was close collaboration between the two parties with regular, generally weekly, meetings. 

“ The quality of the drawings provided by Beca were great,” said David Moore of Grayson Engineering. This made quality control easier when the project unexpectedly came under extreme time pressure.

A worldwide shortage of Cor-ten steel at the time moved the goal posts dramatically. Despite this, Grayson Engineering was able to source material and draw on and co-ordinate other fabricators to meet the target dates of both projects in mid-2009.

The main trio dealing with the bulk of the plate cutting, fabrication and welding were Grayson Engineering (Auckland), Energyworks (New Plymouth) and TP Engineering (Auckland).  Other companies involved around the country were Jensen Steel Fabricators (Tauranga), PFS Engineers (Hamilton) and Kawerau Engineering (Kawerau.)

“ The most heartening thing about this project is the coming together of professionals with a can do attitude who want to make it happen” said David Moore of Grayson Engineering. “That we completed the fabrication to time, and that it all fitted exactly on site is a reflection of the diligence and attention to detail of everyone involved.”

And the willingness to work shifts around the clock!

“The work time was condensed dramatically – with the equivalent of 6 months work having to be completed in just three, ” said Tony Herewini of TP Engineering.

Quality management throughout was an absolute necessity. There was no room for error. If it did not fit on site in New Caledonia – it would have been a nightmare for sub subcontractors, with major cost implications given the high price of labour over there.

The result was a flawless perfect fit – on deadline!  It shows the level of expertise engrained in our local industry…..100% world standard operators.

There are two achievements of scale that make this an impressive project. Not only is the Contact Energy Bridge the longest steel ladder deck bridge in New Zealand – it also involved the largest application of aluminium coating in a single steel structure in Australasia. 10,000m2 of applied 220m aluminium metal spray protects the bridge from corrosion from the sulphur laden geothermal gas emissions below.

A massive earth fill over the steam pipes was considered at first. But when durable, lightweight flexible steel can be protected against even ferocious corrosive activity – no other option stacked up better than a steel ladder bridge. It was the smart, safe, and efficient choice all round.

Alastair Blackler from Fulton Hogan elaborated. “Steel was used for the bridge superstructure as it offered superior span lengths and lighter loads on the bridges spread footing foundations. This was important in maximising the clearance between the bridge and Contact Energy’s steam pipes and other infrastructure. Because the ladder girder style bridge is a simple pre-assembled form it is easy to construct. It significantly reduced the number of heavy lifts (up to 70t) to 14, or one per span. Constructing an alternative pre-stressed concrete Super Tee or Double Hollow Core Bridge would have required multiple heavy lifts for each span.”  Blackler also remarked on the importance of the high quality of the fabrication from Eastbridge. “ It helped us to exceed our programme targets during the on-site assembly and erection.”

According to Bruce Mellsop of Eastbridge, there were scale challenges in terms of tight production schedules. Only steel could deliver in the timeframe – but it required meticulous planning to keep on target. “ With 650 tonnes of pre-assembled steel, and with girders 28 metres long, delivery had to be made in a particular order so the builders can put it up with ease progressively.”

In the end this vast bridge was put up so quickly it was literally amazing. The pier structure of ladder bridges is designed to be simple and efficient, and the high strength to weight ratio of steel was an important factor in easy handling and speed.

As Mellsop pointed out, “Each span from pier to pier was bolted together on the ground, then craned into place in a matter of hours. This meant that the construction team could assemble and place a span each week.”
From an aesthetic point of view – few will see how remarkable the structure is from ground up. When all is complete, when you drive straight over State Highway One and come down to the Taupo-Rotorua intersection – now you will be instantly on a bridge to Waikato River for half a kilometer. “The public will barely perceive they are on a bridge.” said Mellsop.

This steel bridge construction project is a significant one for the industry – as it shows what can be achieved with steel with today’s modern fabrication technology combined with technically advanced protective coatings.

To meet the specifications of the New Zealand Transport Agency, the lifespan of the coating had to be 35 years to first maintenance. Aluminium matched that lifespan, with an expectation of lasting over 40 years before touch ups will be required.
Craig Ross of Napier Sandblasting explained some of the challenges of the biggest spray job in Australasia. “ The coating system in itself is not complicated to apply – but the scale of the job and the fact that aluminium can sometimes make equipment temperamental, meant a lot of late nights.”

New Zealand historical thinking about road bridge construction was totally avoided in the choice of steel for the superstructure of this project. We have been slow to follow the rising international trend. Instead, kiwi ingenuity was applied at all levels. As a result, steel ladder deck bridges may become as popular as they are globally as modern, urban, simple and architecturally striking solutions.

The sheer scale of the project is more easily seen by comparing it with a modern high-rise. The 20 story Deloitte Centre in Queen Street, Auckland is 34,000 square metres including the basement. Project Century covers 60,000 square metres – incorporating seven building. The largest being the Warehouse and packaging hall (at over 45,000 square metres) and the smallest being the brew house (at around 900 square metres.)

Scale aside, the really huge story behind what made the construction of this new brewery a world-class success -– is the extraordinary collaboration that took place.

As Mike Sullivan of D&H Steel Construction points out “ It doesn’t matter how well we perform in the factory, ultimately you are measured by what happens on site and how you work as a team. The interaction between Mainzeal, Beca and D&H showed how working together early in the design phase allows smart problem solving and creates considerable savings in time and costs.”

The project benefited not just from state of the art technology – but a commitment to making the most of everyone’s specific expertise from the earliest stages.

Mike Turner of Mainzeal agreed. “I was impressed with the Structural Steel trade. What was achieved by the “solutions based attitude” we all shared is one of the many success stories of the project.”

“Project Century” (as the project was known to all stakeholders) had to be the ultimate in collaboration for many reasons.

The imperative was to ensure it was sustainable from economic, social and environmental perspectives. With construction underway before design could be completed, the early focused teamwork allowed for creative solutions, quality management, and greatly reduced wastage – increasing the effective and economic use of steel. High-level collaboration was needed for problem solving complex and intricate tasks on the one hand, and at the other end of the scale – the sheer size of trusses.

Perhaps the most notable collaboration was the design and methodology input by D& H Steel Construction, Beca and Mainzeal into the 150m long multi span steel trusses in the warehouse: a process managed by Mainzeal.

The trusses were assembled on the ground and erected in 3 parts, 2 or 3 bays at a time. This required careful design of the splices, the lifting points and the exact placement of the 4 cranes. The steel frame consisted of 33 trusses spanning 150 meters, with two massive spine trusses
running the length of the building. The truss connections were designed and fabricated in a way that would accommodate the temporary deflections expected during the erection phase.

The stunning glass entrance façade is another impressive collaboration. D&H was engaged by Glass Metro Tech to design and build the steel structure to support the inclined glazed cylinder.

“ The accuracy required was to the millimeter and when you see the size and complexity of the glass structure you can appreciate why this tolerance had to be applied,” said Sullivan.

Also of note is the Tank Farm structure with no vertical columns. To erect this required some very innovative solutions.

Why was structural steel the obvious choice?

Structural steel played a significant part in this project along with precast and insitu concrete to form the structure. Steel was used primarily because the long spanning trusses could be erected faster than any other product. Also,as Turner points out “ Steel has the ability to transfer loads over a great distance – for example massive trusses supported by just two columns.” From a site point of view, steel is very convenient. Fabrication and painting is done off site, with only the erection process required.

Objectives and deadlines have been well met. The first test beer was produced in the new brewery plant on 15 September, with intentions to start producing and packaging product for retail sale in early 2010.

This project certainly passes the taste test and the ingenuity test brilliantly! Not only did the team develop a deep respect for each other’s expertise – but the whole industry can now celebrate what New Zealand specialists in this field can achieve. Worth raising a glass or two over! Cheers!

For this project, New Zealand structural engineers at Aurecon developed an advanced earthquake damage avoidance system, the first of its kind in the world.

The protected column base detail with ringfeeder springs

It has now been internationally recognised by the Institution of Structural Engineers (UK) in their 2009 Structural Awards. Aurecon (Wellington), structural designers for the project, have won “the Education or Healthcare Structure” category. The judges commented that Te Puni was “A worthy project bringing true innovation in the field of seismic design and economy to what could have otherwise been a very expensive building.”

The major structural engineering innovations that attracted the judges’ attention are located in the buildings’ clever bracing systems.  Conventional design of steel framed structures for seismic events has depended on member ductility and the acceptance of a certain amount of damage to frame members. In this new system, “connections” rather than frame members are the focal points for energy dissipation. The result is a structural design, where the steel frames themselves will escape significant seismic damage.

Sean Gledhill, Project Leader Aurecon shared his delight for the project, the talented team, and implications for New Zealand structural engineering as a whole. “The skills and knowledge in our industry are cutting edge.”  Gledhill enjoyed working with a dynamic design team including Geoff Sidewell, Dr Darrin Bell, and external peer reviewer, Dr Charles Clifton.

An elevational view of the structure during construction

It was crucial to the projects success that there was a high level of collaboration with all involved, especially with the design build contractor Hawkins Construction, who grasped the potential of the new technology immediately. “This damage avoidance system was presented, reviewed and constructed whilst other technologies were still in laboratory testing phases”, Gledhill said.

Steel was also crucial to the projects success. “The Te Puni project demonstrates how steel as a material can be manipulated to form complex parts and systems without a major impact on cost or speed of a project.”

 What logistical challenges set the scene for this innovation?

348 dormitories were to be built on a steep hill in a condensed 18-month program. That hill was 2km from a major seismic fault. To also meet the needs of the buildings secondary role as the University’s disaster operations centre, it was paramount to take earthquake protection to the max.

The clever response was to invent an economic system for the complete protection of the multi story steel framed buildings. “Basically” said Gledhill; ”it meant taking the ideology of base isolation you’d use on a hospital project and taking it into a steel frame building. We approached the problem in a different manner to traditional design. We considered where damage is normally allowed in a building, and brainstormed ways of protecting the primary frame. We used an enhanced jointing system at beam column joints as conceived by Dr Charles Clifton, when he worked at the Heavy Engineering Research Association (HERA), and created a column base protection device for frames.”

A sliding hinge joint

The Te Puni buildings are literally designed to “rock” – and not just in terms of being a great place to live.  The damage avoidance system involves a new form of foundation connection which allows the buildings to lift during an earthquake – then rock using railway damper technology to control movement in a controlled and safe manner. The joints between columns are allowed to slide, absorbing seismic energy. The movement is very small, but essential.

This technology is a step change in design philosophy. Whilst being safety compliant for earthquakes currently means “ a standard that ensures people can walk out alive” – this damage avoidance technology takes it to the new level of ensuring that the building “still functions” after an emergency.

The project also takes seismic design of flexible multi storey steel frame buildings in a new direction.  Developers now have the option to fully protect a steel building with similar performance to base isolation. There are now cost effective, sustainable and original solutions with applications for developers in seismic areas all around the world.

Designing a social place, and one that is safe for as many probabilities and improbabilities as you can imagine is part of leading architects and structural designers task. The kiwi ingenuity behind Te Puni shows that anything that can be made can be made better, smarter, safer.  Well done to all involved!

Architect: Architectus

Structural Engineer: Aurecon

Contractor: Hawkins Construction

Steel Constructor: MJH Engineering

 The AMP Society Building in Customhouse Quay Wellington is one of the cities most significant and distinctive historic buildings with a Category One rating with the New Zealand Historic places trust.

Architects Stephenson&Turner, had already designed an award winning entrance to the building and refurbished the upper floors, terrazzo stairwells and lifts. The next challenge was a practical one:  the need to create additional floor space for office accommodation. This would help the buildings inspiring 1920’s classical features meet the future by catering inventively for modern office needs.

The problem to counter was the fact that the existing ground floor was dominated by a double-height former reception area – so it was too imposing to be used as office space and too vast to be effectively air-conditioned. (You cannot blow air down six and a half metres.) The solution was creating a new mezzanine level. One which has turned out to be visually and structurally stunning – appearing light and airy as it hovers in space, yet with the extraordinary tensile strength of steel.

The mezzanine solution may seem an obvious one – but the limitations of a heritage site posed huge logistical challenges. How do you execute the heavy construction of a mezzanine floor when you cannot risk damage to heritage features, you cannot attach anything to ornate marble pillars, or spill or rip anything on original heritage carpet below? Whilst the only solution is to hang a floor off the floor above using high tensile stainless steel rods – how do you bring core structures in when the front door is out of bounds because the outside façade and the central space is heritage rated?

The expertise required to solve these challenges was considerable. For example, the main feature, the bridge between the floors (an all steel 3 dimensional truss) could not be adjusted on site. As Troy O’Donoghue of Stevensons Structural Engineers Ltd pointed out, the only alternative was bringing it through a double height window, then erecting the mezzanine floor inside like giant meccano.

“Between Fletchers Interiors, the Architects, Aurecon (previously Romulus Consulting Group) and ourselves – the whole team worked everything out exactly. The bridge between 2 floors just sneaked in the window with millimetres to spare”, he said. “We suspended it off the HIAB crane and poked it through at right angles to avoid hitting the tram wires.”

Structurally only steel could achieve the design objectives as Murray Robertson, architect from Stephenson&Turner, pointed out.

“There are many different grades of steel. It has great strength particularly when used in tension as we have on this project. We actually were able to create a lighter structure than we even thought possible when we started the project. The balustrade posts are only 50mm x 10mm and are at 1500mm spaces.”

Steel also provided opportunities to cleverly conceal services leaving a cleaner ceiling with only light and sprinklers visible. There is a lot going through the trusses and unusually for a New Zealand office space the new ceiling uses perforated steel tiles.   Integrated active chilled beams were also utilised. These contain the air supply, cooling and lights, all in one unit, and threaded through the trusses.

From an aesthetic point of view, steel was a brilliant modern contrast. The architects put something very new in a 1920’s classical space – and it worked beautifully.

 “The light elegant glass and steel structure was designed to provide a contemporary contrast to the solid robustness of the marble stone and bronze surrounding space. While the new structure contrasted with the existing it also had a rigid order that related to the classical columns and reflected the classical nature of the space.” Robertson explained.

“Mission accomplished” with not a scratch on any heritage spot, or a spot on any heritage carpet. Few would realise the lengths gone to achieve it – a testament to the expertise of all involved…..and the versatility of steel.

Wellington’s Chews Lane Precinct – Supreme Winner & Excellence Awards Winner

Construction of Chews Lane Precinct took place in a challenging urban environment, with very restricted access off Victoria Street. Heritage buildings have been imaginatively restored and retrofitted, and thoroughly contemporary new buildings seamlessly integrated.

The entire project involved two thirds of the city block and encompasses 19 retail stores, 15,000 square metres of office space, steel structured apartments and 200 car parks. The Chews Lane Apartments straddle two 8 floor concrete podia rising 12 levels to 20 floors.

Steel’s part: In the tower apartments ductile structural steel frames provided resistance to wind and seismic loads, while allowing the broadest possible openings to spectacular views. Working in structural steel also resulted in a faster construction programme. MJH Engineering Limited was the fabricator and erector.

Westfield Manukau City – Excellence Winner

The Westfield Shopping Centre expansion at Manukau City was a huge undertaking:  57 shops and kiosks, a Sky City Cinema Complex and on two levels under the cinemas – parking for 360 vehicles, with a separate structural steel car park for another 270 vehicles.

Steel’s part: D&H Steel Construction Limited provided the shop drawings and erected and fabricated a total of 1,800 tonnes of structural steel. Although concrete was considered, steel was the cost-effective and practical choice with its high strength to weight ratio, flexibility, and construction speed factor.

Auckland International Airport – Excellence Winner and Merit Winner.

More than 30 proposals were intensively studied before the best solution for Auckland International Airport’s expansion needs was identified: add a new floor to the existing Pier A.  This was accomplished while the airport kept running and more than 17,000 international passengers moved through the pier every day.

Steel’s Part: In such challenging conditions structural steel comes into its own.   Whole structural units were assembled in DH Steel’s workshop before being delivered to site, often during odd hours, where they were quickly erected with no interruption to airport operations.

OfficeMax Building  – Excellence Winner

The new OfficeMax building at Highbrook Business Park in Auckland was an exercise in raising the quality bar all round, and doing it smartly and cost-effectively. The modern warehouse is almost 15000 square metres with attached office space of over 4000 square metres. In the office section, a full height internal atrium provides natural light is a dramatic architectural feature.

Steel’s Part: The advice of steel fabricator and erector Enterprise Steel Limited was incorporated into the design of this 550 tonne steel structure. The result was an economical structure, a smooth rapid build, and a spacious warehouse/office complex made for minimal maintenance and maximum modernity.

Yealand’s Estate Winery – Merit Winner

Not only was the Yealand’s Winery designed to merge into the beautiful rolling landscape of Seddon (south of Blenheim), but a core strategy was to set the standard for Winery and Industrial “Green Building” in New Zealand. A full treatment facility enables waste to be irrigated back to the grapes without any negative environmental impact.

Steel’s Part: John Jones Steel Limited fabricated and erected 320 tonnes of steel. The stable, energy efficient, and inspiring environment created is sure to contribute to great Sauvignon Blanc and Pinot Noir….

Club Tower – Merit Winner

The Latitude group’s Club Tower in Christchurch is the first office development in the South Island to be certified under Green Star, receiving a 5 Green Star rating under Office Design. The building includes use of recycled steel in the structure, CO2 monitoring and control, and the use of a wide range of environmentally sustainable materials. Club Tower has thirteen levels, with stunning views across Christchurch City to the Southern Alps.

Steel’s Part:  John Jones Steel Limited fabricated and erected the steelwork.  The ability to recycle steel through many structural lives reduces the environmental impact of building structures.

Newmarket Rail Station is a critical part of “Project Dart”- Ontracks $600 million upgrade of Auckland’s rail network and the Auckland Regional Transport Authority’s programme for improving Rail Stations. At the gateway to Newmarket’s fashionable Broadway – this spacious world-class facility is a resolutely modern public building. The concourse structure is 5m above the track and the Southern Concourse roof is between 12.5m (centre) and 14m (outside edges) above the track level. The length of the building is approximately 37m. The architects, OPUS International Consultants, have reflected the futuristic urban appeal of highly efficient city rail transport services.

“Highly efficient” is also a hallmark of the construction of the building. A professional integrated approach to project management, the flexibility of steel construction on a challenging site, and the precise art of steel fabrication really came to the fore.

Steel constructors George Grant Engineering, Hawkins Infrastructure project managers and Opus engineers worked closely together with Ontrack for safety around trains – and the degree of collaboration on quality, environment, and health & safety management was exacting and impressive.

With all the high spec requirements, and the unusual challenges of a site with live trains running underneath, steel was a logical choice for many reasons. For strict earthquake and environmental safety standards alone, a steel structure has many significant advantages. The strength and lightness of steel framing, its ductility, and the processes of fabrication means steel can be engineered to meet precise requirements.

The limited access to the site by day, space restrictions on site, its closeness to live tracks, and with residential apartments within a stone’s throw on either side presented many organisational challenges. The engineers, architects and construction team developed a unique scheduling plan.

Work had to be carefully phased, and pieces of the steel structure brought in in segments. The versatility of steel, its strength combined with light weight, and its ability to be easily formed and joined, solved many logistical problems.

“Our only option was to shut trains down at night and drive up the track. We brought in roof rafters that were 26 metres long each, and tree heads for the rafter support structure that were 6 and ½ metres square” said Scott Delacey of George Grant Engineering.

Extremely large members were made in sections in the workshop and erected on site with high spec QA requirements calling for “near impossible weld procedures”.

“There was careful planning in the fabrication stage. We had to set up a jig in the workshop to build the “tree heads” – the column structures designed to support the roof. The only way to do it was to actually build each one upside down in the shop then take them to the site to erect.” Delacey pointed out.

On site, they stood 12 metre high columns, filled them with concrete, then welded “tree heads” on all, and on top of these, a rafter. In order to fit the roof structure on, everything needed to be exact within 2 millimetres.
The design and the projects unique challenges made steel the obvious choice for the structure. It is simply easier with steel than concrete to do things like make pipes look like flower heads, or to integrate with glass. Curves using steel beams bent to a certain radius or segmented curves or combinations of both can create members that follow the outlines of irregular facades, arches or domes.
As Delacey commented, “You can form steel. You can bend it, roll it, cut it and do all kinds of things with it. With concrete you have to pour it into the thing.”

The Newmarket Station is a great example of how great design, brilliant logistics, exacting attention to detail from all contractors, and the strategic choice of steel meant construction challenges were waded through without a hitch. The result is a very strong and uncompromising building that commuters will love.

The Deloitte Centre is a great example of how steel offers significant benefits in modern construction, particularly in city sites. The use of steel beams solved time and site constraints and was the flexible choice in achieving the architectural vision – creatively, technically, and practically.

Nick Clements of Steltech Structural Limited explained, “With Steel you can produce a much slimmer structure than concrete columns and beams, so it allows more floor space and a lighter feel to the whole structure. It also reduces the overall mass of the building which reduces the size and cost of
the foundations required. It is faster to erect, as there is no requirement for formwork or the time to cure concrete. Much of the steel fabrication is done off site so it reduces the manpower and time on site – making for a safer smoother flowing worksite.”

A major construction issue of the Deloitte Centre was the need to ensure that the building fitted with the facade of the historical Jean Batten Building. The old building’s stud height remains 2.7m yet sophisticated ceiling services have been installed through custom made welded steel beams.

Modern multi story buildings tend to have greater heights between floors due to the need for installing air conditioning and other services. With traditional construction methods the services would have to pass under the floor beams, but with welded steel beams the designer can pass services through the
beam webs saving this height.

Significant use of cut outs in the beam webs means all the services tucked neatly in the ceiling space with large ducts going right through big beams.

Steltech worked closely with the fabricators, D & H Steel Construction.

“The fabricator supplied us with electronic files for each different beam design that we fed through to our CNC profile-cutting machine to cut the holes,” Clement said. “Designers can now push how they use steel by thinking outside the square on how welded beams can be made to almost any shape
or size and with holes pretty much wherever they want them.”

Possibly the most powerful first impression to all who enter The Deloitte Centre is a result of the dramatic steel cantilever in the foyer. The long spanning capability of steel enables the creation of large and graceful areas of unobstructed space in multi-storey buildings. Here the effect is extraordinary. The architects, local firm Warren & Mahoney and international company Wood Bagot, have achieved their goal of a stunning urban frontage.

“The glazed canopy on Queen Street not only provides shelter to the footpath along the building boundary but is also a striking element at the main entrance. The primary structure consists of a 900mm deep steel box beam, which is 42 metres long. At the main entrance the dramatic box beam cantilevers a total of 12 metres. The glazing is supported off 14 large polished stainless steel arms, which in turn hold the canopy’s stainless steel spider fixings,” said Richard Voss, architect from Warren & Mahoney.

The whole building is based on pushing design boundaries from conventional to very modern, with the lowest possible environmental impact. As a result The Deloitte Centre is a smart and efficient building worthy of its 5 Star Green Star rating from the Green Building Council.

The double ventilated façade on Queen Street is part of the project’s “Green” objectives. As Voss explained, it reduces the solar gain on the West facing façade by virtue of the stack effect. The warm air rises in the 600mm wide glazed cavity to outlets at high level. Computational Fluid Dynamic (CFD) modelling was undertaken to predict the air movement speeds and heat patterns within the double ventilated façade. It will efficiently keep the tower warmer in winter and cooler in summer. Another green feature is the harvesting of rainwater from the building. This will be used to flush the toilets. Also, upper level interiors have 2.9m
studs reducing the need for artificial lighting.

Overall, The Deloitte Centre shows how steel construction offers new solutions and opportunities for architects to cost-effectively expand their artistic expression and meet today’s challenges for inspiring, smart, efficient, safe buildings.

The two storey steel trusses opening out to the courtyard

Design engineer Jeff Clendon of Holmes Consulting Group says that because the structure follows the height restriction plane, the building is partially cut into the ground and has different heights along its length. “The roofs and floor diaphragms span horizontally to distribute earthquake loads to a mixed system of concrete shear walls acting in the transverse, north-south direction, with moment-resisting steel frames acting in the longitudinal, east-west direction. The moment-resisting steel frames extend down the length of the building on the north and south facades, and essentially run from roof level down to level three, which is the lowest “ground” level. The level three diaphragm is connected to the surrounding ground by a series of rock anchors. Below this level, longitudinal basement walls distribute residual earthquake loads to the ground.

“With floor-to-floor heights being at a minimum, steel beam depths were critical; both the composite and non-composite beam design required non-standard solutions in critical areas to maintain head heights. A number of beams required haunches and steel plating to satisfy the design constraints. The roof is typically of lightweight construction, consisting of low-pitched membrane or iron roofing on timber packing over steel purlins and regular steel rafters, with posts to the concrete floors below.”

Prefabricated bathrooms still wrapped in plastic were on a critical path of the construction programme

SCNZ: “What was your biggest challenge in this project?”

Cliff Saunders: “The site resembles a quarry, with no setting down room. This meant we were in deliver-and-erect mode, craning the steelwork straight off the truck and bolting it into position immediately. We even did this with the three trusses, the two biggest of which were 18m long and 6.5m deep. We transported all three as one load, weighing a total of 15 tonnes, from Dunedin to site and got them up the same day. As the project advanced, each finished floor area became our setting down space for the next stage of steel.”

The building provides vehicle and pedestrian access to the adjacent Lakeside West and Lakeside Central West buildings via underground tunnels. The Quadrant Hotel is destined to be a designer 4 star hotel and construction is scheduled for completion by November 2009.