Quincy Memorial Bridge

Information and Findings From Missouri's Historic Bridge Inventory

Bridge Features

Superstructure: steel, rigid-connected, continuous Baltimore through truss, with multiple-span deck girder and stringer approach spans
Substructure: concrete abutment; concrete piers with art Moderne detailing under main span; concrete spill-through piers under deck girder approach span and steel stringer approach spans floor/decking: unknown
Other features: upper chord and inclined end post: 2 channels with cover plate and built-up, double channel lacing; lower chord: 2 built-up channels with lacing; vertical: 2 laced channels; diagonal: 2 laced channels; lateral bracing: 2 angles; strut: angles with lacing; floor beam: built-up plate girder; guardrail: steel;
Bridge plates on Illinois side - Large Plate: "QUINCY MEMORIAL BRIDGE Dedicated to the memory of the men and women who served our country in the Armed Forces Erected June 13, 1930", Small Plate: "QUINCY MEMORIAL BRIDGE Mississippi River Redecked 1982 by State of Illinois FA RT. 63 SEC 1-2By Proj. BH-F-63 (37) Loading HS2O S'I'R. N0 001 0019"

Discussion of Bridge

Early 20th century motorists wishing the cross the Mississippi River at Quincy faced two options: riding the ferry that traversed the river in the warm-weather months, or crossing on the vehicular runways cantilevered from the sides of the CB&Q railroad bridge. With neither alternative especially palatable, the local citizenry boosted for a highway bridge at this point off-and-on for years. Plans to build the bridge finally began to coalesce in 1927 with the formation of the Quincy Memorial Bridge Company, a consortium of local business interests. The corporation proposed to build a highway bridge at Quincy and pay for its construction through tolls levied on bridge users. To design the immense structure, the Quincy Memorial Bridge Company hired the Chicago-based Strauss Engineering Corporation-the civil engineering firm later responsible for the design of the Golden Gate Bridge. As delineated by Strauss, the proposed bridge extended 1256 feet, with two 628-foot, rigid-connected Baltimore through truss spans carried continuously over a center concrete pier in the river's channel. The Kelly-Atkinson Construction Company, also of Chicago, was contracted to build the bridge's approaches and erect the superstructural steel; the Foundation Company of New York would build the 36 river piers. Construction on the bridge proper commenced on June 15, 1928, with construction of the river piers began in September. Laborers worked on the concrete piers despite massive floodwaters along the Mississippi in November 1928 and again in March 1929. Carrying the cantilevered weight of both main spans, the center pier was the most critical. Men in a pneumatic caisson excavated almost 118 feet below the river's surface to found the center pier on bedrock. The substructure was completed in September 1929. Steelworkers erected the multiple beam and truss spans in 1929-30, assembling the last of the superstructural steel by March 1, 1930. The Quincy Memorial Bridge was opened ceremoniously to traffic on June 16, 1930. It remained under the aegis of the Quincy Memorial Bridge Company as a toll crossing until the construction bonds were retired in 1945. Ownership of the bridge was then transferred to the states of Missouri and Illinois, and the bridge was made toll-free. In 1982, the St. Louis Bridge Construction Company was hired to reconstruct the bridge's deck. The original concrete floor was removed at that time and replaced with a steel grid deck. Other than this, the Quincy Memorial Bridge remains essentially unaltered. Bridges over the Mississippi River comprise some of America's longest examples of vehicular truss construction. With over 400 miles fronting on the great river, Missouri possesses several notable Mississippi River bridges. Seven of the state's longest crossings over the Mississippi are included in the statewide bridge inventory, all of which are considered eligible for the National Register. The Quincy Memorial Bridge is historically significant because it served as a pivotal transportation link between Illinois and Missouri on a major interstate highway, and it had a major impact on the socioeconomic development of northeastern Missouri. Featuring an unusually configured continuous truss design and multiple girder approach spans, the bridge ranks among Missouri's most monumental examples of steel truss construction-a superlative, well-preserved example of its type.

Bridge Considered Historic By Survey: Yes

View Original PDF Historic Bridge Inventory Sheet