Traffic-resumes!
‘Bridge Bashes’ as they are euphemistically known among rail engineering professionals, are when high sided vehicles – taller than the bridge they are passing beneath – collide with the structure, invariably causing both rail and road chaos.
However, where there are enough unintentional impacts – and at Hardwick Road in Pontefract, West Yorkshire the toll is 61 collisions since 1990 – then the structures in question start to be compromised.
The major operation swings into action
“In addition to the problems and delays caused by the numerous collisions, the bridge was also of a construction that caused other problems for Network Rail, with hidden critical elements,” said Partner, Jon Livesey
The decision was taken, therefore, to replace the bridge’s superstructure, including its deck which carries two ballasted rail tracks over the A639 Hardwick Road.
HBPW was asked to complete the engineering drawings and after a lot of planning and closure of the bridge for a little over 48 hours, engineers worked tirelessly through the night to guide the new structure into place.
New for old
“In simple terms these are concrete filled steel tubes which absorb any vehicle impacts before the bridge itself, ensuring that the main superstructure is not compromised prematurely.”
Jon added: “Because of the relatively short engineering possession period – when the road and rail lines close for the duration of the work – the contractor, AMCO, decided to install the bridge using self-propelled mobile transporters which installed the bridge, collision protection beams and cill units simultaneously, a total of 250 Tonnes of bridge driving down the road – quite an impressive sight!”
New superstructure is slid into place