Brighton i360 takes top structures award

The Institution of Structural Engineers has announced the winners of the 2017 Structural Awards; presenting the top Supreme Award for Structural Engineering Excellence to the winner in the Tall Structures category,  the British Airways i360 viewing tower in Brighton.

Standing 162m high and costing around £42m, the British Airways i360 attracted its share of controversy in Brighton as other parts of the city's seafront heritage stood decaying and unfunded. Initial teething trouble left the viewing pod and passengers stuck half way up the tower for several hours during one 'flight' after its opening in August 2016.

But the judges of this year's Structural Awards have only praise for the 3.9m diameter steel tower – the Guiness Record holder for 'world's most slender tower' – designed by Jacobs and built by Hollandia, Nardo Hoogendijk and JT Mackley & Co.

The tower was delivered by barge directly to the beach and erected by a top-down method without the use of cranes. It features purpose-designed perforated cladding to minimise vortex shedding, and sloshing liquid dampers to limit wind-induced dynamic movements. The judges said: 

'The tower comprises 17 ‘cans’, each weighing between 50 and 100 tonnes, which were jacked up one by one in a top-down method of construction by using a jacking frame. This avoided the use of unfeasibly large cranes, and ensured that all construction occurred safely at ground level. And you’ll be happy to know that over 60% of the energy used to lift the pod each time is recovered on its descent. A remarkable feat of engineering.'

The 2017 Structural Awards winners

Tall or Slender Structures: British Airways i360; Jacobs

Long Span Structures: San Mames stadium, cable roof extension, Bilbao; IDOM

Vehicle Bridges: Destructor Bridge, Bath; COWI

Pedestrian Bridges: Jet d'Eau, Geneva; INGENI

Small Projects: The Pump House, London; Webb Yates Engineers

Oustanding Value: ElevArch; Freyssinet/BHA

Click here for more on the winners