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The Haupt Truss The Sayers Bridge in Thetford, Vermont is said to be the only example of the Haupt truss in New England. Curiously, the Sayers' truss lacks the defining lattice structure of the braces shown in Haupt's patent drawings. Instead of the lattice-like assembly of braces, it has a long and high timber arch similar in construction to Burr's arch. See below. Note that the brace configuration in Haupt's truss implementation distributes, at least for the first several truss panels, compression forces more directly to the abutments than does the Sayers Bridge truss. This is a key feature of the Haupt patent. The Sayers' truss, rather, performs like a "multiple Kingpost truss with auxiliary arch." The differences between the two truss implementations, then, are more than trivial. Herman Haupt was born in Philadelphia, Pennsylvania in 1817. He died in 1905 in Jersey City, New Jersey. He graduated from West Point in 1835. He resigned his commission to become district superintendent and chief engineer for the Pennsylvania Railroad. In 1839, he designed and patented the Haupt bridge truss. When the Civil War began, he was drafted to serve as superintendent of military railroads. He rose to the rank of Major General. Civil engineers may remember him for his text books on bridge construction and his work on the five-mile railroad tunnel through the Hoosic mountain range in northwest Massachusetts.
From Spanning Time Vermont’s Covered Bridges, by Joseph C. Nelson
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