|Location Map ( geo)|
|The viaduct as seen from the A34|
| Northbound: October 2009|
Southbound: Summer 2010
The Wolvercote Viaduct is a twin-bridge structure on the A34 immediately south of the Peartree Interchange. It crosses the A40, the Oxford Canal and the Oxford to Birmingham railway. It is linked by an embankment to the Thames Bridge, where the A34 crosses the River Thames.
The 2010 built viaduct was a replacement for the 1961 original which, on coming up to 50 years old, had water leaking through the deck joints causing deterioration. In Summer 2008 a temporary southbound bridge was built and opened in March 2009, with northbound traffic switched to the old southbound bridge. The old northbound bridge was then demolished and replaced and in October 2009 northbound traffic was switched back to the new bridge so that the old southbound bridge could be replaced. The replacement wasn't conducted in a similar manner to parallel widening due to the close proximity of the Peartree Interchange, which meant that the road had to be on the same alignment as it approached it.
Although the new bridge met modern standards that the old one fell short of (including the length of the sliproads at Peartree), it didn't have any new lanes, despite traffic forecasts suggesting this section of the A34 would soon be running well above capacity. It's thought that this decision was made on cost and space grounds.
The original viaduct
This was built as part of the Oxford Ring Road Western Bypass. Construction started in 1959 and it was completed in 1961. The Western Bypass opened on 22 November 1961.
It was 850 feet long and had 12 spans which were conveniently arranged to straddle the railway line, Oxford Canal and A40, and at the same time provide maximum similarity of beams. The foundations consisted of 50 to 60 foot long piles and the precast, reinforced pier legs sat in reinforced concrete pile caps.
The contractor was Higgs and Hill of London and contract cost was £400,000.