This article does not cite any sources. (January 2013) (Learn how and when to remove this template message)
Incremental launch is a method of building a complete bridge deck from one end of the bridge only.
The first bridge to have been launched appears to be the Waldshut–Koblenz Rhine Bridge of 1859 followed by the Rhine Bridge, Kehl in 1861. The first incrementally-launched concrete bridge was the 96 metre span Caroní River Bridge, a box girder bridge over the Caroní River in 1964.
The normal method of building concrete bridges is the segmental method, one span at a time.
The bridges are mostly of the box girder design and work with straight or constant curve shapes, with a constant radius. 15 to 30 metre box girder sections of the bridge deck are fabricated at one end of the bridge in factory conditions. Each section is manufactured in around one week.
The first section of the launch, the launching nose, is not made of concrete, but is a stiffened steel plate girder and is around 60% of the length of a bridge span, and reduces the cantilever moment.
- Woronora River Bridge, 2001, the largest incrementally-launched bridge when built
- Redcliffe Bridge, 1986
- on YouTube