McMillin Bridge
The McMillin Bridge is a concrete half-through truss bridge crossing the Puyallup River, in Pierce [County, Washington], built in 1934.
The main span of the bridge is long, which was the longest beam span or concrete truss in the US when it was built. It was part of Washington [State Route 162|State Route 162] until it was replaced by a new span in 2015.
Design
The bridge design uses a hollow-box system, which was suggested to the design company of W. H. Witt Company by Homer M. Hadley.The bridge was then built by Dolph Jones.
The bridge was built to replace a steel span that had been washed out by the flooding river in 1933.
Because of economic conditions, the concrete design was chosen over a steel design, with a savings of $826, in addition to lower maintenance costs.
The bridge is unusual in that it combines concrete with the half-through truss design, which was usually built with steel.