Commendation – Scale Lane Bridge, Hull

This landmark 57m span pedestrian and cycle swing bridge connects Hull city centre and its Old Town conservation area with the east bank of the River Hull.

FACT FILE
Architect: McDowell+Benedetti
Structural engineer: Alan Baxter & Associates
Steelwork Contractor: Qualter Hall & Co Ltd
Main Contractor: Qualter Hall & Co Ltd
Client: Hull City CouncilHull City Council’s brief for the Scale Lane Bridge was that it would become an icon, increase connectivity across the city, unlock regeneration potential, and augment use of the river frontage. The brief also required navigation clearances to be maintained at all times for small boats and the bridge to be able to open for larger vessels.

This innovative swing bridge, which is believed to be the first in the world that allows pedestrians the unique experience of riding the structure while it opens and closes, has achieved all of these criteria.

The bridge’s sweeping form creates a choice of two curving pedestrian routes – one gently sloping, the other stepped. The circular geometry of the hub means the walkway is always in contact with the river’s west bank as it swings open, allowing people to walk on and off at all times.

The structure’s capacity is 1,000 people while opening and up to 4,000 people when closed.

“It’s more than just a bridge, it’s a destination,” says Jonathan McDowell, Partner of project architect McDowell+Benedetti. “People come to enjoy a ride on the bridge as well as the views up and down the river.”

“The use of steel was fundamental to the design and it is the only material that could have produced this cantilevering, non-uniform structure,” says Jim Gardiner, Alan Baxter & Associates’ Project Engineer.

Steel has also allowed the design to incorporate the sweeping curves developed by the architect, while retaining the inherent strength of the steel plate required within the structural design.

Structurally, the bridge consists of a curving steel spine cantilevering from a three-dimensional braced ring (hub) that is approximately 15m in diameter. The spine is a hybrid structure with the root section conceived as a diagrid/shell and the tip as a shell. Steel plates clad the surface of the walkways while horizontal bracing provides additional longitudinal stiffness.

The hub structure consists of columns connected to horizontal steel wheel structures, forming both levels of the three dimensional ring. The circular hub section acts as a counterbalance to the cantilever section, with concrete slabs at both levels.

Summing up, George Orton, Qualter Hall Managing Director says: “The design of the bridge is unique and a manufacturing achievement due to the complex hybrid spine structure. It has been a privilege to be involved in a project that not only serves a practical purpose, but has also created a new cultural landmark for the city.”

Judges’ Comment

This swing bridge over the River Hull offers the memorable experience of riding on the bridge while it opens. The judges appreciated the high quality detail and fabrication of the hybrid spine structure, which forms the sweeping shape.

The team successfully integrated a number of complex mechanical, electrical and structural components into this unique rotating structure.

The bridge is greatly enjoyed by the public.