Canton Viaduct is a distinctive stone railroad bridge in Canton, Massachusetts (USA) erected in 1835 by the Boston and Providence Railroad Corporation (B&P) 0.3 mile (0.5 km) south of Canton Junction for their mainline service between Boston, Massachusetts and Providence, Rhode Island. It was the final link to be built on the 41 mile railroad between the two cities, and is the only structural Blind Arcade viaduct ever built in the United States. It was the longest bridge in the nation when it was built and second only to London Bridge in the world.

It is the oldest surviving railroad bridge in New England and has been in continuous service for 174 years; it now carries high-speed passenger and freight rail service. The Viaduct is located on Amtrak's Northeast Corridor at milepost 213.74, reckoned from Pennsylvania Station in New York City, and at the Massachusetts Bay Transportation Authority's (MBTA) milepost 15.35, reckoned from South Station in Boston. The Canton Viaduct was erected in 1835 by the B&P, one of the first New England railroads, shortly after its 1831 founding.

Without the influence of Joseph Warren Revere, owner of the Revere Copper Company a major stockholder of the B&P and a member of its Board of Directors, the Canton Viaduct would not have been built. There were better routes through other towns for the location of the railroad line from Boston to Providence. However, building the railroad through Canton placed the line close to Revere's mill, where a spur connected the mill to Canton Junction and undoubtedly gave a boost to Revere's copper business.

The other influencing factor that caused the Canton Viaduct to be built was a fatal accident in 1832 on the Granite Railroad, which used inclined planes to cross a valley. The original plans called for the use of inclined planes to cross the Canton River Valley but were changed after the inclined plane accident and a bridge was built instead. This unique bridge was designed by two US Army Corps of Engineers officers - Captain William Gibbs McNeill and Major George Washington Whistler both were West Point graduates, topographical engineers and brothers-in-law.

The bridge was built by Dodd & Baldwin (Pennsylvania). Around this time Russia was interested in building railroads so Tsar Nicholas I sent workmen to draw extensive diagrams of the Canton Viaduct. He later summoned Whistler to Russia as a consulting engineer to design the Moscow–Saint Petersburg Railway, on which two bridges were modeled after the Canton Viaduct.

A scale model bridge of similar design is on display at the Oktyabrsky Railroad Museum in St. Petersburg. The bridge resembles a giant, rusticated stone wall supporting a train deck about 60 feet (18 m) above the Canton River, the east branch (tributary) of the Neponset River.

The stream pool passes through six semi-circular arches in the bridge, flowing to a waterfall about 50 feet downstream. The coping is supported by 42 segmental arches (21 on each side) that join the tops of 44 buttresses (22 on each side) tied to the walls internally and externally. The viaduct is an archetype in bridge design due to its two parallel walls and cavities, the walls are five feet thick with a four foot gap between them joined with occasional tie stones.

More construction details are available in the original specifications. The structure is often identified as a "multiple arch" bridge because the deck arches appear to extend through the bridge to the deck arches on the opposite side, which they do not; each independent deck arch is only four feet deep. The only arches to penetrate the walls are six river arches and two roadway arches.

Since bridges are classified by their support system, the Canton Viaduct is more accurately described as a double Blind Arcade viaduct - deck arches support the outer limits of the deck (beyond the walls) and walls support the middle of the deck with stone slabs spanning the cavities; neither the deck arches nor buttresses penetrate the continuous walls. When the bridge had a single set of tracks the rails were placed direclty over the walls as the cavity's width is less than standard gauge. When the bridge was double tracked in 1860 both sets of rails were placed directly over the walls and deck arches.

The Thomas Viaduct (Maryland, 1835) and Starrucca Viaduct (Pennsylvania, 1847) are examples of true multiple arch viaducts, with semi-circular arches supported by piers, and no continuous walls.

Similar to 0 things you like: