SANRAL
Client
Project Location
Johannesburg, South Africa
BRIDGES & WALKWAYS
Nelson Mandela Bridge Proposal
Henry Fagan Consulting Engineers & Project Managers proposed a bridge design for the Nelson Mandela Bridge over the railways linking Braamfontein and Newtown in Central Johannesburg. Henry Fagan Consulting Engineers & Project Managers felt that the site required a bold, sculptural solution from an architectural point of view, and that a cable-stayed bridge would not offer enough of a contrast from the clutter of railway masts, cables and tracks present on site.
The design, based purely on structural principles combining bending moments with prestress forces, comprises a tower and three “waves” of decreasing height, lending a zoomorphic quality to the bridge. The leaning tower counters the cable forces in the top of the fin, and also acts as a strong focal point for the Newtown suburb, earmarked by authorities for urban regeneration. A variation on the design included an enclosed space at the top of the tower to be used as a radio station of museum, accessible via a sloping lift.
The design makes use of locally proven technology (incremental launching & post-tensioning) for a totally unique structure with no precedent anywhere in the world, all the while minimizing disruption to traffic during construction. Ultimately, the design came a very close second to the winning cable-stayed bridge and was not chosen for construction.