Alan MacDiarmid Building, Wellington

width=250New Zealand’s first multi-storey PRESSS building is a true collaborative effort that has seen the implementation of new technology in seismic and component-based concrete construction.

Opened in July 2010, the building comprises four suspended floors of science teaching and research space (with an associated heavy services demand) over a flexible entry floor teaching/conference area. This upper structure straddles an existing service tunnel with a basement each side, and fits between the existing surrounding buildings.

By utilising un-bonded post tensioning and rocking joints within the structure the PRESSS system (PRecast Seismic Structural System) is designed to ensure the building returns to upright without significant structural damage, even after a major seismic event.  The sustainability implications, in terms of life preservation and minimising the financial burden of potential repairs post earthquake, are immense.

Specifically, the PRESSS system reduces displacements under small earthquakes through its high, pre-rocking stiffness, while for larger seismic events potential damage is concentrated towards replaceable energy dissipaters, rather than throughout the structure. Furthermore, the flexibility in the superstructure, achieved at a fraction of the cost compared to a base isolated building, assists to reduce in-building accelerations once rocking occurs. In a science research building where the fit-out and services can be of higher value than the building itself, these features are of huge importance.

The PRESSS system uses prefabricated components meaning site operation is assembly focussed, resulting in improved quality control, reduced on-site waste and noise, as well as accelerated construction. Being demountable also allows for future deconstruction and re-erection elsewhere if required.