swing bridge
between a bony fish and a lost dinosaur
a swing bridge suspended in time
from a single steel sheet, a skeletal structure unfolds

The Crystal Palace Dinosaurs are a unique symbol of the local area. They were built in the 1850s in the grounds of the Crystal Palace and were the first ever life ­sized reconstructions of extinct animals.

A bony fish that over thousands of years metamorphoses into a skeletal bridge. Using biomimetic principles in its geometry, the bridge is ultra-lightweight, super-economical, and touches the land lightly. To control access, the bridge has two positions: resting in the middle of the weir and swinging 90 degrees. The bridge enables access to a national heritage of international importance, the Crystal Palace Dinosaur Islands.

Swing Bridge delivers three specific innovations in its structural formation. The unique circumstances of Dinosaur Island and the need for a secure crossing inspired the structural artwork. The 166-year-old concrete sculptures of dinosaurs are laid out to describe evolutionary development over time. The bridge’s location was chosen to mark the start of this sequence, it also inspired the reference to the precursor to the dinosaurs, the bony fish. To protect access to the Grade-I listed structures, the bridge has been designed to remain in the water and only make its connection to land when access is provided for education and for maintenance.

Longlisted, Landscape, Dezeen Awards 2022
Shortlisted, IABSE Awards, 2022
Winner, GAGA Architecture Award 2022
Winner, Bridge Design, Bridge Awards 2022
Highly Commended, Civic Trust Awards 2022
Highly Commended, Pedestrian Bridges, iStructE 2021
Shortlisted, Infrastructure and Transport, AJ Awards 2021
Shortlisted, NLA Placemaking 2020
BKI Material Prize, Royal Academy of Arts 2019
Shortlisted, NLA Transport & Infrastructure Award 2019

The solution of the Swing Bridge negates the need for a large protective barrier. The unique arrangement also tells a story of evolution, keeps its distance from the dinosaurs and requires only one central foundation. A triangular torsion beam delivers load to the central bearing, its tailored form is minimised in response to the bending moment forces. The skeletal deck structure projects out from the beam’s backbone like form. The bridge form gains overall strength through being widest and tallest over its central support. Form gives strength through geometry in each component of the structure. 

The deck is constructed using an innovative comb arrangement that minimises wastage and maximises strength. each side of the deck is constructed as a single comb structure. From the sheet of the comb one of the prongs is bent up to become the balustrade, one is bent down to form a strut to the lower edge of the central beam, and one remains flat to form the bridge deck. The skeletal comb structure utilised the whole surface of the 10mm steel sheet and the bending technique reduces the amount of welding by 50%.

Minimal thickness of the steel sheet is achieved by optimising resistance with form in the laser cut comb structure. In the evolution of the first bony fish, an undulating movement produces a force to propel it forward. The undulating form of the balustrade and deck resist forces applied to the handrail through a push-pull action. The balusters lean backward and forward along the length of the undulating deck, the outer acting as a buttress and the inner as a tie. The comb’s multiple bent and welded prongs act together like spokes in a wheel to give the undulating form lateral stiffness. The frequency and pitch of the oscillation have been engineered to find the optimum form. The system of construction derived from the comb allows for the direct expression of strength in form through technique.

A story telling process that searches for inspiration in nature has delivered technical innovation in response the unique circumstances of the site. The project was instigated by the long-standing commitment and insightfulness of the friends of Crystal Palace Dinosaur Island, who raised funds from the GLA and through crowdfunding, and delivered through a close collaboration with architects, Tonkin Liu, engineers Arup and locally based fabricators, Cake Industries. 

“An efficient, quirky, low carbon bridge that is full of charm and character”

- Bridge Awards 2022 jury

client friends of the crystal palace dinosaurs
location crystal palace park, london
size 8m span
budget £70,000
status completed, 2021
structural engineer arup
contractor cake industries
photography james balston