Three rivers - the Allegheny, Monongahela, and Ohio - join in Pittsburgh, making the city a natural site for the building of bridges. But the Smithfield Street Bridge stands apart from other Pittsburgh bridges for several reasons: it replaced structures by two well-known bridge engineers, Lewis Wernwag and John A. Roebling; it was the first use in America of the lenticular - or lens-shaped - truss design; and it was one of the first major bridges in the U.S. built primarily with steel.
Lenticular
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YearAdded:
Image Credit:
Courtesy Flickr/RJ Schmidt (CC BY-ND 2.0)
Image Caption:
Smithfield Street Bridge
Era_date_from:
1883
1975
Innovations
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Three rivers - the Allegheny, Monongahela, and Ohio - join in Pittsburgh, making the city a natural site for the building of bridges. But the Smithfield Street Bridge stands apart from other Pittsburgh bridges for several reasons: it replaced structures by two well-known bridge engineers, Lewis…
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