Stevenson Concrete products played a key part in the construction of the Grand Atrium project, a stunning 8,500 square metre public space, at the Auckland War Memorial Museum.

 

The project began when two storeys were excavated, lined and waterproofed in the museum courtyard to create a new 200-space car park and basement storage area. The Grand Atrium structure has been built above this base with sheer walls lining the north, east and west sides. Steel structures form the four legs of a central cruciform structure, which is suspended in the middle of the grand atrium. This bowl shaped building is topped by an impressive low-rise glass and copper dome.

Stevenson Concrete put a great deal of work into developing the correct concrete mixes for this complex and challenging project. We developed a special concrete mix for the perimeter wall, which had two layers of concrete. The first layer was shotcreted and the second layer was a special mix applied between the shotcrete and a removable shutter. The second layer mix needed to be highly workable, with 160mm slump and small aggregate, to go through the tighter reinforcing. It was essentially self-compacting concrete.

Stevenson used a third generation super plasticiser, which is used in self-compacting concrete. Stevenson also supplied the self-compacting concrete mixes used to form an 18.4 metre length beam in two spans. In-situ concrete was pumped to cast the four beams, and Golden Bay Cement’s Microsilica 600 additive was used in the shotcrete mix provided for the excavated area of the new car park. This helped to reduce rebounding, as the shape of the wall was not even. The Microsilica added cohesion to the thicker mix.

 

Partners

  • Hawkins Construction
  • Bill Grace Limited (block work)
  • Stresscrete Dycor (precast flooring)
  • Salmond Reed Architects (heritage building conservation specialists)
  • Holmes Consulting (structural and civil engineering)
  • Connell Mott MacDonald (engineering)
  • Rider Hunt (quantity surveyors)