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Lexington Bridge (Mississippi River)
Encyclopedia
Lexington Bridge is a plate girder bridge
that spans the Mississippi River
between St. Paul, Minnesota and Lilydale, Minnesota
. It was built in 2004 by the Minnesota Department of Transportation
.
The original Lexington Bridge was built in 1965 as part of the proposed construction of Interstate 35E
. However, the bridge did not see much use for a while, because I-35E was not completed between Lilydale
and Burnsville
until the mid-1980s. Construction of I-35E between Minnesota State Highway 5
, just north of the bridge, and Interstate 94
in downtown St. Paul was not finished until the early 1990s. The increase in traffic caused the old bridge to deteriorate faster than expected. As a result of deterioration, and a need to carry more traffic, the old bridge was replaced. The staging of this construction project was notable for keeping four lanes of traffic open during the process. A new span was built on the west side of the bridge, and then traffic was detoured to the new southbound span and the old southbound span. The old northbound span was demolished, and a new northbound span was built. When this was completed, the old southbound span was demolished, and the inner two lanes of the new bridge were completed.
The bridge has an anti-icing system that sprays potassium acetate
onto the bridge surface to prevent frost and ice formation in inclement weather. This is part of a test to see if measured application of chemicals can prolong the life of a structure, as compared to the usual liberal application of sodium chloride
salt.
Plate girder bridge
A plate girder bridge is a bridge supported by two or more plate girders. The plate girders are typically I-beams made up from separate structural steel plates , which are welded or, in older bridges, bolted or riveted together to form the vertical web and horizontal flanges of the beam...
that spans the Mississippi River
Mississippi River
The Mississippi River is the largest river system in North America. Flowing entirely in the United States, this river rises in western Minnesota and meanders slowly southwards for to the Mississippi River Delta at the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains...
between St. Paul, Minnesota and Lilydale, Minnesota
Lilydale, Minnesota
Lilydale is a city in Dakota County, Minnesota, United States. The population was 623 at the 2010 census.-Geography:According to the United States Census Bureau, the city has a total area of , of which, of it is land and of it is water....
. It was built in 2004 by the Minnesota Department of Transportation
Minnesota Department of Transportation
The Minnesota Department of Transportation oversees transportation by land, water, and air in the U.S. state of Minnesota. The cabinet-level agency is responsible for maintaining the state's trunk highway system The Minnesota Department of Transportation (Mn/DOT, pronounced "min-dot") oversees...
.
The original Lexington Bridge was built in 1965 as part of the proposed construction of Interstate 35E
Interstate 35E (Minnesota)
Interstate 35E is an Interstate Highway in the U.S. state of Minnesota, passing through downtown Saint Paul. It is one of two through routes for Interstate 35 through the Twin Cities of Minneapolis and Saint Paul, the other being Interstate 35W through Minneapolis. Thus, both ends of I-35E are...
. However, the bridge did not see much use for a while, because I-35E was not completed between Lilydale
Lilydale, Minnesota
Lilydale is a city in Dakota County, Minnesota, United States. The population was 623 at the 2010 census.-Geography:According to the United States Census Bureau, the city has a total area of , of which, of it is land and of it is water....
and Burnsville
Burnsville, Minnesota
Burnsville is a city south of downtown Minneapolis in Dakota County in the U.S. state of Minnesota. The city lies on the south bank of the Minnesota River, upstream from the confluence with the Mississippi River...
until the mid-1980s. Construction of I-35E between Minnesota State Highway 5
Minnesota State Highway 5
Minnesota State Highway 5 is a highway in Minnesota, which runs from its intersection with State Highways 19 and 22 in Gaylord and continues east and northeast to its eastern terminus at its interchange with State Highway 36 and Washington County Road 5 in Stillwater...
, just north of the bridge, and Interstate 94
Interstate 94
Interstate 94 is the northernmost east–west Interstate Highway, connecting the Great Lakes and Intermountain regions of the United States. I-94's western terminus is in Billings, Montana at a junction with Interstate 90; its eastern terminus is the U.S...
in downtown St. Paul was not finished until the early 1990s. The increase in traffic caused the old bridge to deteriorate faster than expected. As a result of deterioration, and a need to carry more traffic, the old bridge was replaced. The staging of this construction project was notable for keeping four lanes of traffic open during the process. A new span was built on the west side of the bridge, and then traffic was detoured to the new southbound span and the old southbound span. The old northbound span was demolished, and a new northbound span was built. When this was completed, the old southbound span was demolished, and the inner two lanes of the new bridge were completed.
The bridge has an anti-icing system that sprays potassium acetate
Potassium acetate
Potassium acetate is the potassium salt of acetic acid.-Preparation:It can be prepared by reacting a potassium-containing base such as potassium hydroxide or potassium carbonate with acetic acid:...
onto the bridge surface to prevent frost and ice formation in inclement weather. This is part of a test to see if measured application of chemicals can prolong the life of a structure, as compared to the usual liberal application of sodium chloride
Sodium chloride
Sodium chloride, also known as salt, common salt, table salt or halite, is an inorganic compound with the formula NaCl. Sodium chloride is the salt most responsible for the salinity of the ocean and of the extracellular fluid of many multicellular organisms...
salt.