A joint venture (JV) comprising Balfour Beatty, Skanska and Costain has installed two 1,000t bridges as part of the Cambridge to Huntingdon A14 upgrade scheme.

The JV is executing the £1.5bn project on behalf of Highways England.

Using an innovative engineering technique, the bridges have been built at the side of the live carriageway and positioned to keep disruption of the highway to only four days.

During this period, a self-propelled modular transporter (SPMT) lifted the decks of the new bridges, each measuring 44m, into place.

“We’ve found a way to build the two bridges while keeping the A14 open as much as possible and disruption for people locally and road users to a minimum.”

Located at Bar Hill, the new bridges will form an improved junction that will link the A14 to the future local access road between Cambridge and Huntingdon in addition to the existing local road between Bar Hill and Longstanton (B1050).

They replaced the existing one at Bar Hill, which will be demolished next year.

Highways England A14 Cambridge to Huntingdon upgrade project director David Bray said: “Redesigning and building the Bar Hill junction was identified from the start of the project as one of the main challenges we would have to tackle.

“I am delighted that we’ve found a way to build the two bridges while keeping the A14 open as much as possible and disruption for people locally and road users to a minimum. And I am also excited that we’re using such an innovative solution to our challenge, that’s what makes my job so interesting.”

A 21-mile section of the A14 between Cambridge and Huntingdon will be upgraded to three lanes in each direction, including a 17-mile bypass south of Huntingdon, with four lanes in each direction between Bar Hill and Girton, as part of the A14 upgrade scheme.

Scheduled to be completed by 2020, the project includes 34 bridges and main structures, including the 750m-long River Great Ouse viaduct.