- Architect Undercurrent Architects
- Client Undercurrent Architects
Eckersley O’Callaghan designed a free-standing enclosure beaneath a working Network Rail viaduct. The highly non-linear geometry is made up of individually formed, full height elements, each a sandwich of Cor-ten and mild steel-wrapped insulation, fabricated off-site in China, shipped fully formed, craned onto site and bolted together.
Once all connected, the panels form a self-supporting rigid shell with a hidden truss spanning over the archway opening and delicate vierendeel braces stabilising the skylight opening.
Internal spiral cores and braced walls help stiffen the cantilevering shell, maintaining clear distance between it and the viaduct. The shell is bolted to a mass concrete pad which balances the overturning developed by wind loads, the pad itself floating on springs on concrete strip footings to isolate against vibrations from passing trains.
Achieving the delicate balance of a light weight and stiff structure which would not risk clashing with the viaduct or vibrating as trains passed, or undermine the viaduct’s foundations was a challenge. Rigorous Finite Element Analysis and close coordination with Network Rail brought outstanding results.