Deep underground a box has been built inside a box with special protections against vibrations from Crossrail and Northern line tunnels.
A new entertainment venue, the Outernet is being built next to Tottenham Court Road, and while most of the publicity has been on the above-ground visual effects, the heart of the Outernet is a 2,000 people venue built underground. The Crossrail tunnels next to the venue were built with a floating track to reduce vibrations, but the venue’s location includes closer than expected proximity to the tunnels, and also to the Northern line escalator box.
The main Outernet structure is conventional concrete and steel, but in order to stop the venue being affected by vibrations from the railway tunnels, they’ve had to build another box inside the concrete box with vibration absorbers.
The roof was built on the floor of the main structure, then lifted up to its final location on a series of jacks.
Last month, the construction firm, Skanska says that it has completed the final stage of the box within a box, lifting the 400-tonne steel and concrete roof into its final position 8 metres high using 14, 75-tonne jacks. After this, 70 perimeter columns were installed underneath so that the roof could be carefully released from the jacks onto the permanent columns.
The ‘box within a box’ is now structurally isolated from the rest of the basement structure.
The part of the Outernet that most people will see will be The Now Building, a live broadcast environment that will contain 360-degree, 8k enabled floor-to-ceiling screens.
The development has not been without controversy though, as part of the complex of buildings, it has seen the gutting of the old buildings lining Denmark Street, and while the facades will be retained, inside them will be modern, and music fans often like a bit of dirt in their venues that evolved organically rather than being built as part of a masterplan.
Just look at the reaction given to the demolition of the form jam factory, the Astoria, which was frankly, a ghastly germ-infested dump – and people loved it.
The Outernet London is on course to open next summer.