Bridges of Newport (1)

Transporter Bridge

The bridge was designed by French engineer Ferdinand Arnodin. It was built in 1906 and opened by Godfrey Charles Morgan, 1st Viscount Tredegar, on 12 September 1906.[

Newport Museum holds a silver cigar cutter which was presented to Viscount Tredegar on the day of the opening, as a memento of the occasion.

Design

The design was chosen because the river banks are very low at the desired crossing point (a few miles south of the city centre) where an ordinary bridge would need a very long approach ramp to attain sufficient height to allow ships to pass under, and a ferry could not be used during low tide at the site.[4]

Principal dimensions

A Corporation of Newport drawing dated December 1902 is calibrated in metres. The height of the towers is 73.6 metres (241.5 ft), and the height to the underside of the main girder truss above the road level is 49.97 m (163.9 ft). The span between the centres of the towers is 196.56 m (644.9 ft), and the clearance between the towers is quoted as being 180.44 m (592.0 ft); however, including the cantilevered sections, the main girder truss gives the bridge an overall length of 236 m (774.3 ft). The distance between the centres of the anchorage caissons is 471.06 m (1,545.5 ft). Power to propel the transporter platform or gondola is provided by two 35 hp (26.1 kW) electric motors, which in turn drive a large winch, situated in an elevated winding house at the eastern end of the bridge. This winch is sufficient to drive the gondola through its 196.56 m (644.9 ft) total travel at a speed of 3 metres per second (9.8 ft/s)[citation needed].

This is the oldest and largest of the three historic transporter bridges which remain in Britain, and also the largest of eight such bridges which remain worldwide).[citation needed]

When compared with Middlesbrough's Transporter Bridge, the Newport Transporter is 5 m (16 ft) taller, but 23 m (75 ft) less in overall length. It also utilizes approximately 1,400 long tons (1,400 tonnes) of steel compared to 2,600 long tons (2,600 t) used to construct Middlesbrough's Transporter (not accounting for steel used in foundations or concrete anchors)[citation needed]. This difference in weight is mainly due to the Newport bridge making use of cables to support and induce tension into its structure to a far greater extent than the Middlesbrough bridge.