Don’t know about you, but I find bridges structurally interesting. This is surprisingly the 5th bridge I’ve now filmed for my channel. Although the other four were covered bridges: three used by cars and one a RAILROAD bridge! And just like those other bridges, this one is also on the National Register of Historic Places.
So, what is a Pennsylvania Through Truss? It’s a Pratt Truss, which was patented in 1844 by Thomas and Caleb Pratt. This truss design was used from 1844 into the early twentieth century. The “through” part means one can see through it both above and below the deck. The deck is what the vehicles use.
At the time of filming this, I didn’t know why it was also known as the “Checkered House Bridge”. I had driven through the bridge to see if I could find just such a house. Alas, I did not. However, I did find this:
“The bridge acquired the name the Checkered House Bridge as a nod to a nearby 18th-century brick house, which boasts a distinctive pattern of burned bricks on one end. Even today the house is easily visible from the interstate.”-https://vtdigger.org/2013/03/17/in-this-state-2/
“The Winooski River Bridge, also known locally as the Checkered House Bridge, is a historic Pennsylvania through truss bridge, carrying U.S. Route 2 (US 2) across the Winooski River in Richmond, Vermont. Built in 1929, it is one of only five Pennsylvania trusses in the state, and was the longest bridge built in the state’s bridge-building program that followed massive flooding in 1927. The bridge was listed on the National Register of Historic Places in 1990.
The Winooski River Bridge stands in a somewhat rural area of eastern Richmond, set roughly east–west across the Winooski River just north of the bridges carrying Interstate 89 (I-89). It is a single-span Pennsylvania through truss structure, 368 feet (112 m) in length and 21 feet (6.4 m) wide. Its portals have a clearance of 17 feet (5.2 m), and the bridge stands about 32 feet (9.8 m) above the water on concrete abutments. Its trusses have extra reinforcing sub-struts to improve its performance under heavy loads.
The bridge was built in 1929, as part of a major bridge-building program by the state, following flooding in 1927 that destroyed more than 1,200 bridges. The state sought to use standardized designs for as many of the replacement bridges as possible. This bridge, built by the American Bridge Company, is one of the small number that does not follow a standard design, due to difficulties in fitting the standard design to the site. It is the longest single span of the 1,600 bridges built in the three-year rebuilding program, and is one of just five Pennsylvania truss bridges in the state.”-https://en.m.wikipedia.org/wiki/Winooski_River_Bridge