|March 2011 (-33.883 deg., 151.208 deg.) Eddy Avenue Underbridge
I'm standing on Eddy Avenue looking east at the Eddy Avenue Underbridge (1923) that carries trains in and out of Sydney's Central Station. An underbridge is a British term for a bridge that allows traffic to travel below it. Not surprisingly, the bridge and road are named after railway commissioner Edward Miller Gard Eddy (1851-1897). There's a lot of additional information on Sydney's Central Station and it's bridges on the Heritage Council website.
Note the use of sandstone as a facing material on this reinforced concrete bridge. In Sydney the use of sandstone as a facing material (rather than solid sandstone) may indicate a structure is of less significant but it also indicates a change in technology as reinforced concrete became more important. The sandstone on this bridge appears to have become discolored, especially on the railing. I believe some of the sandstone on the station was recently replaced due to similar problems.
The bridge is very wide to carry trains from the eight railway platforms that are located just south of the bridge. All of the trains on these platforms are electric as indicated by the overhead line on the bridge. Much of the infrastructure at Central Station had to be modified as trains went from being powered by steam, to electricity, to diesel fuel during the last century.
The bridge is actually a reinforced concrete pierwall and slab structure that was artfully disguised to look like a stone masonry arch structure. This artifice was used to match the station's architecture while taking advantage of the better performance of reinforced concrete.
Australia's Bridges: Eddy Avenue Underbridge at Sydney's Central Station by Mark Yashinsky is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.