Our Pick
Posted on @rawstates
The first road bridge in the world built on hybrid composite beams
2008
Lockport Township, Illinois
John Hillman's idea was a beam made of a fibre reinforced shell holding concrete and steel, lighter than a steel or concrete girder and far less prone to corrosion. In 2008 a 57 foot single span over Long Run Creek became the first road bridge anywhere built on them. Six of the beams carry an ordinary eight inch reinforced concrete deck. The design is rated for 80 to 100 years with almost no maintenance to the girders.
That was 1 of the hidden places.
Location: documented spot
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