Hayward Main Bridge replacement
Hayward Main Bridge, which links Child Okeford and Shillingstone in north Dorset, is now reopen.
The new bridge, which carries Bere Marsh Road/Hayward Lane over the River Stour, was opened on Friday 14 October in a celebration involving residents and officials from both Child Okeford and Shillingstone.
The £1.5m major project was finished on time and within budget. Raymond Brown Ltd carried out the work on behalf of Dorset County Council, so that essential maintenance to other structures in the county could still take place while this project was underway.
The bridge was essentially on borrowed time due to the progressive corrosion of its deck and beams (opens in a new window), as well as there being other issues. Work carried out to replace the bridge included:
- removal of the existing corroded deck and main beams
- installing new steel beams and concrete bridge deck (created from 122 tonnes of concrete)
- refurbishing the existing stone masonry abutments and central pier above water level
- installing new vehicle restraint parapets on the bridge and on 20m of the approach embankments
- refurbishing the wing walls/retaining walls
- keeping the current bridge wrought iron railings and installing them on the approach embankments
Don't forget to look at images of the work (opens in a new window).
Timelapse video of the bridge replacement
Risk assessment calculations for the strength of the deck were carried out in December 1997, and these calculations limited the maximum load capacity of the bridge to 38 tonne vehicles (which itself was substandard). The condition of the bridge has worsened significantly since 1997. A further inspection was completed in August 2013 and the assessment now limits the maximum load capacity of the bridge to 26 tonne vehicles.
A project was undertaken in 2012 to investigate the below water condition of the bridge abutments and central pier, and to complete all repairs needed below the waterline. A temporary dam was installed in two halves, allowing dewatering and the exposure of the river bed and the foundations of the bridge. This project was successfully completed at the end of September 2012.
The south west retaining wall was reported to have 'failed' in the 1997 assessment report. In 2010 further movement resulted in a depression and cracks forming in the highway surface. The south west wall is now braced with temporary supports. An inspection carried out in 2001 noted bank erosion at the base of all of the walls. Current inspections show rotation of all retaining walls of varying degrees of severity. Ties located between the east wing walls appear to be restraining further moment at present, but long term safety needs to be addressed.