CULTURAL ICONS

VERY HIGH WINDS were factored into detailed computer modelling of Gallery of Modern Art's design by Bornhorst TTW, the company responsible for the structural, civil and facade engineering of the five-storey gallery.

The engineers analysed the building for various loadings and for earthquakes and high winds. Wind pressures used in the computer modelling were obtained from a scale model, which was then tested in a wind tunnel.

Richard Green, director of Bornhorst TTW, says that the engineers were keen to see how the structural steel roof, with its complicated curved shapes and large cantilevers and spans, would behave in high winds.

"We were concerned that the cantilever could start to vibrate with very high pressure on the roof and in high winds," he says.

As facade engineers on the gallery, the team handled four facades, each with a variety of interfaces and corners. The west-facing wall featured a black box' of black anodised aluminium sheet, while the north wall was glazed with timber and fixed battens for shade and cooling. Along the east side, the riverside terrace is heavily glazed, and the south has a so-called white box' of low iron star fire glass with a translucent interlayer. Material for each facade was sourced from specialist suppliers in the US and Italy.

The main building was a reinforced and pre-stressed concrete frame with spans up to 24 metres, required to support the loading of crowds and heavy sculptures.

Another challenge was in the design of the foundations. "Underneath part of the site there was very poor material, mainly because it was so near to the river," says Green. "We worked on a foundation design that would overcome this effect, to ensure the slab on the ground wouldn't settle."

For more details, contact Bornhorst TTW, c/o Taylor Thomson Whiting (NSW) Pty Ltd, 48 Chandos Street, St Leonards, NSW 2065, phone (02) 9439 7288. Email: ttwsyd@ttw.com.au.

Story by: Trendsideas