Media centre

Wednesday 8 Oct 2008

A DAY’S WORK FOR 120 YEARS OF RAIL BENEFITS

Region & Route:

| Wales & Western: Wales & Borders

| Southern: Wessex

| Wales & Western

| Southern

It may have been standing for over a century, but thanks to a new method of bridge replacement, the Pill Bridge, in Avonmouth was replaced by Network Rail in just eight hours. This technique, being piloted in the West Country for the first time, forms part of Network Rail’s ambitions to complete engineering work in less time.

Most of the bridge construction work was completed in advance, away from the railway to minimise the amount of time the railway would need to be closed.

The bridge's walkway, hand railings and stone ballast were assembled first before the bridge deck was slotted into place. The number of hours that the railway line was closed for this improvement work was significantly cut back by 75%.

Weighing in at 117 tonnes, the new railway bridge near New Pill Stream is built to last 120 years and is a more robust structure than the replaced bridge, which was over a hundred years old.

Dave Ward, route director, Network Rail, says, “This project went really well. We delivered a more reliable infrastructure and brought the railway back on track on schedule - all within a day. The design of Pill Bridge, which has a short structural span and is single track, provided an ideal opportunity to trial this new delivery method."

The good weather conditions also played a critical role in the project as a 1000-tonne crane was required to remove the old bridge. The crane was also used to lift the new bridge at a height of 26 metres to put in place. The new bridge is a steel-concrete composite structure, with a length of 14 metres.

The old Pill Bridge was a single span structure, originally constructed in 1899. The abutments and wing walls were constructed from stone, and the superstructure comprised a mixture of early steel and wrought iron main girders and cross girders.

Despite some minor repairs to the steel and ironwork in 1975, a recent detailed examination highlighted areas of significant corrosion throughout the steel and ironwork. Additionally there were fractures and open joints to the abutments, wing walls and pilasters.

The railway line was closed at 10am on Sunday (28 September) and reopened on the same day at 6pm.

The £800,000 project was managed by Network Rail and delivered by Carillion.