Protected Bridges Under Close Analysis

Two listed footbridges dating back to the mid 1800’s when rail building was at its height, are set to be given a 21^st century makeover but only when HBPW has completed some sophisticated analysis.

Cottingham and Beverley stations in the East Riding of Yorkshire are both located on the Hull Bridlington Seamer line.

Each features a cast iron arch rib bridge over the line, however, both recently failed assessment tests prompting the need for further investigation. Partner Jon Livesey takes up the story.

“We were originally contacted by AmcoGiffen as part of the CP6 Renewals Buildings Framework and these two structures fell under the spotlight.

“They are NER standard footbridges dating back to the Victorian period and there are only about 12 remaining on the rail network.

“When such bridges fail initial assessments that is not necessarily the end of the matter since there are more precise analysis which enable us to glean more accurate bridge ‘capacity’ data, key to determining exactly what needs to happen in the short term or, more to the point, what can wait until a later date.”

The technique used is 3d Finite Element Analysis and is currently being undertaken in both cases.

“An FEA almost applies a reverse principal to what many would regard as the norm,” said Jon, “using the least conservative assessment technique in order to glean the maximum capacity of the original structure.”

He said this was the most effective way to accurately represent the stresses in each of the structures.

“Once we have that information we will use the resulting model to inform what exactly needs to happen to each of the bridges in terms of renovation or improvement. However, we already know that Cottingham will require an amount of strengthening work and there is a plan to introduce additional safety features by increasing the height of the parapet.”