Spencer’s cable work bridges gap

It has been awarded a £2.2m contract to scale the Alvsborg Bridge, in Gothenburg, envelop the main cables, and set up a dehumidification system to restrict further corrosion of the main cables.

Since it was constructed in 1969, the 933-metre long structure has played a key part in international events. In 1995 it was painted green to mark Gothenburg’s hosting of the World Championship Athletics. It was also the finish line for the 2005-06 Volvo Ocean Race.

Spencer, based in Barrow on Humber in North East Lincolnshire, won the work after safeguarding cables in a similar scheme on the Humber Bridge.

Spencer claimed the Yorkshire and Humber Construction Best Practice Award for innovation on the Humber Bridge project – after devising a solution to scale the heights of the Humber Bridge using specially designed gantries. These gantries provide a safe environment, and allow teams to work above busy carriageways whilst causing minimal disruption.

They finished the contract one year early and the same team is looking forward to heading up their first overseas project as main contractor.

Project manager Jim Mawson said: “We are carrying out the work for Trafikverket, the Swedish Transport Authority, and the client’s engineer Cowi.

“The work we are carrying out there will be similar to that which we carried out on the Humber Bridge. It involves wrapping the main cables in neoprene, then heat welding the laps to make them airtight.

“We will then install a system which drives dry air through the cables, taking out the moisture and restricting further corrosion. This will be powered by a plant and control room which will be built in the bridge’s anchorage structure.

“In addition to this we will be painting the supporting hanger cables on the bridge.” The project is expected to begin in April, and be finished by August.