Demountable Aluminium Dome

The dome is a 30 metre diameter hemisphere, completely demountable and easily portable. Designed to have a high load capacity it is constructed using 100mm diameter hollow aluminium tubes, which are up to 3.2m long and weigh only 16kg each.

Since our client regularly operates overseas, we needed to produce a design which would be accepted by European and North American authorities. To aid this we used Eurocode 9 for the aluminium design and followed accepted norms recommended by both UK and US standards for temporary structures.

We carefully detailed the connections to speed erection and dismantling while also simplifying fabrication. One aspect of this was the omission of welded end caps on the bars. Instead the tubes have been accurately laser cut to receive flat projecting plates.

The bars and node connections have been designed so they can be bolted at one end and left to hang free. This means one person can lift and bolt the bars into position, so reducing the number of people required to build the dome and avoid temporary props.

We used Oasys GSA to model the dome, running a non-linear p-delta analysis, which enabled us to consider robustness of the dome against snap-through failures. More than 250 load cases were considered in the analysis, which were repeated for numerous ground conditions.

The dome has been designed to support heavy loads of up to 500kg on each upper node, in various patterns in addition to strong winds. A total load carrying capacity of over 25 tonnes. The dome was conceived, designed, detailed and fabricated in only four months. Ready for its first use at Glastonbury Festival 2009.

aceaward
Winner of the Building Structures Award (small firm)
ACE Engineering Excellence Awards 2010

  • Client: Bassline Circus