Eads Bridge

Infobox_Bridge
bridge_name= Eads Bridge

---

caption=1983, from Library of Congress HAER project
official_name=
also_known_as=
carries= 4 highway lanes
2 MetroLink tracks
crosses= Mississippi River
locale= St. Louis, Missouri and East St. Louis, Illinois
maint=
id=
design= Arch bridge
designer=James B. Eads
mainspan= convert|520|ft|m|0
length= convert|6442|ft|m|0
width= convert|46|ft|m|0
clearance=
below= convert|88|ft|m|0
traffic=
open= 1874
closed=
toll=
map_cue=
map_

map_text=
map_width=
coordinates= coord|38|37|45|N|90|10|47|W|region:US_type:landmark|display=inlineInfobox_nrhp | name =Eads Bridge
nrhp_type = nhl


caption =
location= East St. Louis, Illinois
lat_degrees = 38
lat_minutes = 37
lat_seconds = 41
lat_direction = N
long_degrees = 90
long_minutes = 10
long_seconds = 17
long_direction = W
locmapin = Illinois
area =
built =1867
architect= Eads,Capt. James B.
architecture= Other
designated= January 29, 1964cite web|url=http://tps.cr.nps.gov/nhl/detail.cfm?ResourceId=716&ResourceType=Structure
title=Eads Bridge |accessdate=2008-07-03|work=National Historic Landmark summary listing|publisher=National Park Service]
added = October 15, 1966
governing_body = Private
refnum=66000946cite web|url=http://www.nr.nps.gov/|title=National Register Information System|date=2008-04-15|work=National Register of Historic Places|publisher=National Park Service] The Eads Bridge is a combined road and railway bridge over the Mississippi River at St. Louis, connecting St. Louis and East St. Louis, Illinois.

The bridge is named for its designer and builder, Captain James B. Eads. When completed in 1874, the Eads Bridge was the longest arch bridge in the world, with an overall length of 6,442 feet (1,964 m). The ribbed steel arch spans were considered daring, as was the use of steel as a primary structural material: it was the first such use of true steel in a major bridge project.cite web| last = DeLony| first = Eric| title = Context for World Heritage Bridges| publisher = International Council on Monuments and Sites| url = http://www.icomos.org/studies/bridges.htm| accessdate = 2007-02-06]

The Eads Bridge was also the first bridge to be built using cantilever support methods exclusively, and one of the first to make use of pneumatic caissons. The Eads Bridge caissons, still among the deepest ever sunk, were responsible for one of the first major outbreaks of "caisson disease" (also known as "the bends").cite journal |author=Butler WP |title=Caisson disease during the construction of the Eads and Brooklyn Bridges: A review |journal=Undersea Hyperb Med |volume=31 |issue=4 |pages=445–59 |year=2004 |pmid=15686275 |doi= |url=http://archive.rubicon-foundation.org/4028 |accessdate=2008-06-19] Fifteen workers died, two other workers were permanently disabled, and 77 were severely afflicted. [cite web|url=http://www.nps.gov/jeff/historyculture/upload/eads.pdf|title=James B. Eads and His Amazing Bridge at St. Louis|publisher=National Park Service|accessdate=2007-03-19]

The Eads Bridge is still in use, and stands on the St. Louis riverfront between Laclede's Landing on the north and the grounds of the Gateway Arch to the south. Today the road deck has been restored, allowing vehicle and pedestrian traffic to cross the river. The rail deck has been in use for the St. Louis MetroLink light rail line since 1993.

History

Built by the St. Louis Bridge Construction Company, the Eads Bridge was built as the first link to Illinois over the Mississippi River at St. Louis by the St. Louis Merchants Exchange. [ [http://www.scripophily.net/merexofstlou1.html Merchants Exchange of St. Louis 1880's - Early Commodity market - Eads Bridge Vignette - scipophily] ]

The domination of the river trade was no longer as important as before the American Civil War, and Chicago was fast gaining as the center of commerce in the West. The Bridge was conceived as a solution to the futile quest to reverse this new found eminence.The bridge, generated in controversy, was also considered a radical design solution, though the ribbed arch had been a known construction technique for centuries. The triple span, tubular metallic arch construction was supported by two shore abutments and two mid-river piers. Four pairs of arches per span (upper and lower) were set eight feet apart, supporting an upper deck for vehicular traffic and a lower deck for rail traffic.

Construction involved varied and confusing design elements and pressures. State and federal charters precluded suspension or draw bridges, or wood construction. There were also constraints on span size and regarding the height above the water line. The location dictated a change from the low Illinois floodplain of the east bank to the high Missouri cliff on the west bank of the river. The bedrock was exceedingly deep. ["From material recorded by "Kevin Murphy, Historian HAER, April 1984" in the public domain."]

These pressures resulted in a bridge noted as innovative for precision and accuracy of construction and quality control. Utilization of cast chromium steel components is arguably the first use of structural alloy steel in a major building construction. (Though the bridge as actually completed contained large - and unknown - amounts of wrought iron.) Eads argued that the great compressive strength of steel was ideal for use in the upright arch design. This decision resulted from a curious combination of chance and necessity, due to the insufficient strength of alternative material choices.

The particular physical difficulties of the site stimulated interesting solutions to construction problems. The deep caissons used for pier and abutment construction signalled a new chapter in civil engineering. Unable to construct falsework to erect the arches because they would obstruct river traffic, Eads's engineers devised a cantilevered rigging system to close the arches.

Although recognized as an innovative and exciting achievement, the Eads Bridge was overcapitalized during construction and burdened with debt. With its focus on the river, St. Louis had a lack of adequate rail terminal facilities, and the bridge was poorly planned to coordinate rail access. An engineering and aesthetic success, the bridge was bankrupt within a year of opening.

Granite for the bridge came from the Iron County, Missouri quarry of Missouri Governor and U.S. Senator B. Gratz Brown who had helped secure federal financing for the bridge. [Past & Repast = The History and Hospitality of the Missouri Governor's Mansion - Missouri Mansion Preservation, Inc. -1983]

The Merchants Exchange eventually lost ownership to the Terminal Railroad Association of St. Louis. The Exchange, fearing a Terminal Railroad rail monopoly on the bridges, would then build the Merchants Bridge (which in turn would eventually be taken over by the Terminal Railroad. The Terminal Railroad transferred the bridge to the City of St. Louis in 1989 in exchange for the MacArthur Bridge.cite web | url=http://www.terminalrailroad.com/history5.php | title=TRAA History | publisher=Terminal Railroad Association of St. Louis | accessdate=2008-04-09]

In 1998, the Naval Facilities Engineering Service Center investigated the effects of the April 4, 1998 ramming of the bridge by the barge Anne Holly. The ramming resulted in the near breakaway of a riverboat casino ; several recommended changes reduced the odds of this happening in the future. [Marine Accident Report: Ramming of the Eads Bridge by Barges in Tow on the M/V Anne Holly with Subsequent Ramming and Near Breakaway of the President Casino on the Admiral, St. Louis Harbor, Missouri, April 4, 1998By United States National Transportation Safety Board, National Transportation Safety Board, United StatesPublished by DIANE Publishing, 2000ISBN 1428996303, 9781428996304]

ee also

*New Mississippi River Bridge
*List of crossings of the Upper Mississippi River

References

*cite book | author=Cook, Richard J. | title=The Beauty of Railroad Bridges in North America -- Then and Now| publisher=Golden West Books, California (USA) | year=1987 | id=ISBN 0-87095-097-5
* Miller, Howard S. and Quinta Scott; The Eads Bridge University of Missouri Press; Columbia & London: 1979
*

External links

* [http://tps.cr.nps.gov/nhl/detail.cfm?ResourceId=716&ResourceType=Structure National Historic Landmark Designation - Statement of Significance]
* [http://www.asce.org/history/brdg_eads.html Eads Bridge] - the History and Heritage of Civil Engineering webpage (American Society of Civil Engineers)
*
* [http://bridgepros.com/projects/eads/ Bridge Pros: Eads Bridge]
* [http://bridges.midwestplaces.com/mo/st-louis-city/eads/ Bridge info] at Historic Bridges of the United States.
* [http://maps.google.com/maps?ll=38.631287,-90.179&spn=0.025311,0.041757&t=h maps.google.com] zoomed in, hybrid mode
* [http://www.gigapan.org/viewGigapan.php?id=2290 High resolution panoramic image of an Eads Bridge span]
* [http://memory.loc.gov/cgi-bin/query/r?ammem/hh:@field(DOCID+@lit(MO0361)) Library of Congress ] HAER record
*Whmc stl photodb|keywords=eads+bridge|title=Eads Bridge

Crossings navbox
structure = Bridges
place = Mississippi River
bridge = Eads Bridge
bridge signs = "St. Louis MetroLink"
upstream = Martin Luther King Bridge
upstream signs =
downstream = Poplar Street Bridge
downstream signs =