Housing more than 2,500 staff, the Spark site was the single biggest city office building platform in New Zealand at the time of construction. Four separate buildings, linked by a rooftop glazed atrium and flying bridges, make up more than 30,000m² of floor space.
Calibre Consulting provided a design solution involving a purpose-designed economical flat beam, precast floor system. By using pre and post stressing to minimise floor depth, we were able to incorporate the large ducting services required for 5-star Green rated buildings. The floor system also allowed us to include large cantilevers beyond the column lines, which creates the appearance of floating floors.
We also completed a sophisticated and dynamic analysis for seismic design, which led us to use precast concrete shear walls around the core of the building and allowed us to minimise the building’s column sizes. This innovative approach provides enhanced aesthetic appeal to the building, increasing the building’s commercial viability.
Other challenges included designing the atriums and flying bridges to allow for large differential movements between buildings induced by seismic events.