With the exception of not inconsiderable weathering, the physical appearance of our-beloved Nanjing Yangtze River Bridge has remained unchanged for its 55 year history. That’s now changing, with the installation of protective rings around its piers.
To give them their proper name, flexible guided anti-collision devices (FGAD), are presently being fitted to what is arguably Nanjing’s most iconic structure, giving the Bridge its first splash of colour since a 2018 restoration.
Installation of the FGAD around pier #6 of the Nanjing Yangtze River Bridge was completed on 12 February. Work is at present continuing to fit the devices around piers #2 thru #9.
The FGADs are eye-catching red, and are comprised of steel composite, polymer, energy-absorption materials and other components, reports The Paper.
Extending to 1.5 metres below the water line and 2 metres above, the devices rise and fall with height of the Yangtze, to offer the Bridge, and indeed passing ships, protection in the event of a collision.
While appearing to be little more than floats, there is considerable science behind the FGADs.
The devices work by prolonging the impact time between a ship and bridge’s pier. This gives the ship additional time and space in order to turn and avoid a full-on collision with the pier.
The upcoming issue of Ocean Engineering has in fact an article on this very topic, saying, ”In this way, the ship can retain most of the kinetic energy, and the impact force on the pier can be greatly reduced. Both ship and pier can be protected by the FGAD”.
Our Bridge is also not alone in receiving the high-tech floats. Further downstream on the Yangtze, installation of protective rings around the piers of the Shanghai-Suzhou-Nantong Yangtze River Bridge took place in 2020 around the time of its construction.
The entire Nanjing project is expected to be completed by the end of April.
