Kilmore Street Medical Centre, Christchurch

Thought to be the first building in New Zealand to use PRESSS technology for a steel structure, the Centre is being built using four pairs of structural steel frames, each vertically post-tensioned to the foundations with unbonded, high-strength steel bars. The frames are able to rock during earthquakes, with the post-tensioning providing a restoring force to help the building to return to centre.

The steel bars, at 75mm in diameter and with 4,311 kN capacity, are the heaviest in the Macalloy range. Four of these tendons (factory-wrapped in Denso Tape to resist corrosion) have been fed into each steel frame, coupled to 75mm starter bars already cast into the foundations and jacked at the top using a 300-tonne jack.

The three-level building is also designed to withstand a one-in-2,500-year seismic event. It will house more than 5000m2 of specialist medical facilities, including four operating theatres, patient rooms, and urology, radiology, orthopaedics and fertility clinics.