Building the foundation for an aluminium smelter furnace was never going to be an easy task. But carrying out the project between two fully operational aluminium furnaces, a casting bed and a hot metal carrier passage presented some additional challenges for Amalgamated Builders Ltd.
It is challenges like this which make commercial building all the more exciting, according to Amalgamated Builders Ltd director Bruce Middleton.
Mr Middleton managed the construction of the new furnace foundations — a Gold Reserve finalist in the Pacific Steel Industrial/Utility Project category in the 2008 RMB Commercial Project Awards — at Tiwai Point, near Bluff.
“Over the years we’ve had numerous challenging jobs which people said couldn’t be done, but we like to surprise!”
Amalgamated Builders, in conjunction with Brian Perry Civil, was able to offer an innovative and bold solution to meet the client’s programme without compromising the safety of New Zealand Aluminium Smelters personnel and equipment.
The foundation was constructed as an open-bottomed poured insitu concrete caisson with a specially designed steel shoe cast-in to the bottom edge.
This was constructed at the ground surface above the final position of the structure. By excavating under the perimeter walls from inside the caisson, the caisson sank under its own weight.
Two small diggers excavated at the foot of the walls, transferring the excavated materials to a central point where it was removed with a larger digger situated on a temporary working platform that straddled the caisson structure.
It’s not just tricky locations and molten materials which increase the challenge of commercial building. “Commercial sites are under the spotlight to a greater degree in terms of the Resource Management Act and health and safety requirements,” Mr Middleton says.
Working in the middle of the metal products area of the aluminium smelter required an extremely high standard of health and safety. All employees were required to wear extensive protective gear and to be involved in detailed job safety analysis and meetings for each phase of the work.
Mainzeal Property and Construction Ltd South Island construction manager Graeme Earl says a lot of work goes into meeting all the statutory standards for a commercial building project.
“The legislative requirements involved in commercial building can get quite complicated — compliance with the building code, local council regulations and air quality levels, to name just a few.”
Mr Earl was in charge of building the new Burwood Hospital Surgical Services Unit in Christchurch, which won the national 2007 RMB Commercial Project of the Year.
The need for efficient patient flow was the key requirement for the design of the unit to replace three small, outdated operating theatres and ancillary areas built in 1963.
The unit consists of four elective orthopaedic surgery theatres, a sterilisation unit, a 16-bed pre-op and recovery area, a 12-bed special care unit and a 30-bed surgical ward.
The building was a complex project with several specialised services, including medical gases, HEPA-filtration, humidification and provision for a large amount of clinical equipment installed separately by the client.
“Commercial projects often require more sophisticated services and construction techniques, as well as bigger toys to get the job done,” Mr Earl says.
“But the buzz of co-ordinating a large-scale project and all the different people and factors that involves — that’s what makes it exciting!”