A railway bridge, euphemistically considered to be in the ‘middle of nowhere’, presented a double challenge to engineers who were faced with the ultimate exercise in precision and access.
The two span River Esk Bridge, which is half a mile east of Glaisdale Station in North Yorkshire, carries the single track Guisborough Junction to Whitby line over the River Esk. In addition, it also spans the deep-sided and densely wooded river valley making access extremely difficult.
Engineering Technician Jonathan Bent takes up the story: “The bridge was originally constructed as a three-span masonry arch bridge around 1864 and, some time later, was replaced with a single span steel truss.
“It now carries rail stock in both directions but, as time has passed, so the bridge has slowly deteriorated. Track realignment was poor and needed upgrading however, apart from requiring extremely precise engineering for this particular aspect of a wider programme of works, we had the double challenge of getting lifting gear to site.”
In the event, a special Kirow crane was brought in.
“These ‘train cranes’ have huge lifting capacity and are designed to be totally self-contained so that they can carry heavy loads in front of their buffers and slew sideways with the minimum of impact on neighbouring rails or obstacles.
“We knew that there would be a substantial lifting requirement because the existing timber sleepers and walkways were in poor condition whilst other aspects of the structure were showing signs of deterioration even though the bridge itself still had sufficient capacity,” said Jonathan.
Overall, the existing track support system has been replaced and realigned whilst the existing walkway has also been replaced with new steel frame and GRP mesh, making railside access for maintenance staff much safer.
“There have also been steelwork and masonry repairs throughout with the bridge getting a new lick of paint! This has been a challenging job, largely due to access issues, but it has taken place in one of the most scenic parts of the country, an added bonus for those carrying out the work!” said Jonathan.