A34 Chieveley, Bird Lane South Overbridge
2004
Bird Lane South Overbridge is one of five weathering steel composite highway bridges on the A34 Chieveley / M4 Junction 13 improvement project. The scheme will reduce congestion at this major N/S, E/W interchange, and was carried out under a design and build project.
This three span continuous integral bridge at 30 degree skew is made with weathering steel at a standard minimum headroom of 5.3m. The outline design was an insitu reinforced concrete bridge on this “green-field” site. The weathering steel ladder deck solution was selected to minimise both the initial cost and future maintenance.
The two main girders are 1.4m deep and 10m apart. The transverse girders are 750mm deep, and at 3.2m centres. Integral abutments and the use of weathering steel minimises the future maintenance requirements. Stability of the bottom flanges at the internal piers is provided by inverted U frames.
Fact file
Bridge Owner
Highways Agency
Designer
Mott MacDonald
Steelwork Contractor
Fairfield-Mabey
Steel Producer
Corus
