Innovative solution fast tracks Translink’s bridge programme

Three major sites - the Braid Bridge, Ballymena, along with Coolderry Bridge and the Culbreen Bridge, were all part of the Translink commissioned contract that was awarded in late January 2021.

Before construction work could commence, an intensive two month planning process was required, which resulted in the identification of a more efficient 72-hour single possession solution as opposed to an original two-pronged possession plan totalling 108 hours.

This innovative approach considerably reduced disruption to the rail network by a full day and a half and also allowed the GRAHAM team to de-risk the programme for two of the bridges.

As part of the programme or works, the Braid Bridge works, on a four-arch masonry structure over the River Braid in Ballymena, involved the removal of 70m of twin track, sleepers, ballast and structural fill. Subsequently, the bridge was waterproofed and reinstated, extending the life span of the structure. The track was also re-laid, welded and stressed.

The works were completed concurrently between the morning of March 27 and the early hours of March 30. They were completed ahead of programme, allowing early handback of the network.

Commenting on the successful planning and delivery of the bridge replacement and refurbishment project, Andrew Henry, GRAHAM Contracts Manager, said: “Generally, a multi-site scheme of this complexity would require a prolonged period of advanced planning and programming, sometimes as much as nine months. Demonstrating our technical competency, we were able to develop a more effective solution of a 72-hour single event possession in as little as two months. This ensured a more efficient process and reduced disruption to the network. Significantly, our waterproofing work, involving loose laid sheeting, was the first of its type to be carried out on a ‘live’ Translink asset for a considerable length of time.