Technical Details fabric atrium wall
by David Dexter

The solution to overcome the complex 3-dimensional shape of the hotel atrium wall whilst maintaining the overall sail-like form of the building was to provide a series of shaped membrane panels that could be pattered to the defined geometry.

The membrane is constructed from 2 skins of PTFE coated fibreglass separated by an air gap of approximately 500mm and pre-tensioned over a series of trussed arches. These arches span up to 50 metres between the outer bedroom wings of the hotel which frame the atrium, and are aligned with the vertical geometry of the building. The double-curved membrane panels so formed are able to take positive wind pressures by spanning from truss to truss and negative wind pressures by spanning sideways. Additional cables have been provided running on the surface of the fabric to reduce the deflection of the membrane.

The trussed arches which can extend out from the supports by up to 13 metres are supported vertically at the 18th and 26th floors by a series of 52mm diameter cross-braced macaloy bars. Girders at these floors transfer the load to the core structure. These bars are then pre-tensioned to ensure that the whole structure remains in tension.

An expansion joint is provided for the full height of the building on the right hand side of the wall. This enables the building to 'breath' under wind loads and avoids the exertion of large horizontal loads on the relatively weak bedroom structures.

The resulting form is entirely appropriate for the building and its function with the fabric reducing solar gain into the atrium and providing an effective diffused light quality. It is also appropriate for the Middle-East region where its predicted lifespan and self-cleansing qualities should resist the aggressive environment.