Engineering Department > Structures Group > Teaching > Prestressed Concrete (4D8)
VR model

Torridge Bridge - Virtual Reality Model

Public Version


This version of the page is for public use. It shows VR images but does not give access to the source files. Those are only available within the .cam.ac.uk domain. Local users should follow this link to see the fully activated page.



This page has been constructed by James Stevenson and Chris Burgoyne. The VR model was constructed by James as part of his 4th year undergraduate project in 2003. We are grateful to Steve Denton of Parsons Brinckerhoff for detailed plans of the bridge, from which the VR model was built, and for some of the images displayed here.



General view

The Torridge Bridge carries the A39 road across the river Torridge in North Devon. It was designed by ... and built by ... in 19... It was built by balanced cantilever construction, with internal cables. The bridge is about 2 miles north (downstream) of the town of Bideford, which it bypasses.


The old bridge in Bideford which has been in use for hundreds of years. It has been widened and repaired on many occasions, and provides severe impediment to flow of water, as well as almost blocking river transport.

Bideford Bridge

Corner detail of one unit showing ducts and anchorage
stockpiled units
corner of unit
Stockpiled units


Placing units near pier
launching girder
placing segments
Span nearly complete


Overall VR view
Overall VR model, which shows the outline of the complete bridge. The model includes several fixed views and a flyover, which passes one way along the bridge, and then returns through the box girder.

Boat view
launching girder
placing segments
Concrete can be made semi-transparent to show internal structure


In the cable model the cantilever cables have been shown in red and the continuity cables shown in green
launching girder
placing segments
Both horizontal and vertical cable profiles are correct



construction model The final model shows the construction sequence. The launching gantry is transparent and the segments can be seen being brought forward, rotated and lowered into position. The segments are made trasparent to show the cables being introduced, and then opaque for realism. When the span is complete the continuity cables are introduced and the girder moves forwards. One slight mistake - our bridge was built from the east bank - the real bridge was built from the west.

Segment being transported past a pier
launching girder
placing segments
Partially transparent image


VR view of anchorage
Real view of anchorage
Virtual anchorages
Real anchorages