The west approach consists of six multi-beam spans, measuring feet long, and seven two-girder spans, measuring feet long. The riveted structure was built in and has been modified several times. WJE engineers utilized industrial rope access techniques to perform in-depth condition surveys of the steel superstructure, including documentation of section loss, as well as an arm's length examination of non-redundant bridge elements subject to tension, including vertical and diagonal truss chords, tie girders, hangers, riveted plate girders, and floor beams.
The engineers also conducted routine condition surveys of all substructure elements located above the ground or water line. As part of the surveys, all bearings were observed, and the positions of expansion bearings were measured. WJE employed a variety of access techniques to most efficiently inspect various elements of the bridge. Access to the approach spans was gained using foot and foot boom lifts positioned under the bridges.
To inspect the approach spans and main span deck framing over water, the engineers worked from a boom lift positioned on a spud barge. In addition to the steel superstructure trusses and hangars, rope access techniques were also used to access various approach spans where multiple railroad tracks prevented the use of a boom lift.
WJE's experience with and application of multiple access methods ensured the completion of a comprehensive inspection without any lane closures on the bridge. Wiss, Janney, Elstner Associates is committed to helping our clients solve, repair, and avoid problems in the built world.
Supported by unparalleled laboratory and field testing capabilities, our team of engineers, architects, and materials scientists brings an enthusiasm for problem solving and a hands-on technical approach to every challenge. News About Contact Search. News About Contact. Loading Close. Do Not Show Again Close. The larger bridge was the first to span the Mississippi at Dubuque, and was one the earliest of all Mississippi River bridges.
The superstructures of both the approach bridge and river bridge were fabricated and erected by the Keystone Bridge Company, one of the most important and long-lived bridge companies of the nineteenth century. The importance of the Dubuque and Dunleith Bridge to interstate commerce can hardly be overstated.
It was removed from White Water Creek to a storage site on adjoining farmland in June of where it was stored while the relocation and rehabilitation project was assembled. The City of Dubuque agreed to accept ownership of the bridge from Dubuque County and began preparing engineering plans and specifications.
With the help of many dedicated people, and the financial assistance from the State Historical Society of Iowa, the bridge was relocated to the Bergfeld Recreation Area. In January , the company contracted with the Keystone Bridge Company of Philadelphia to build the original railroad bridge.
Work on the first abutment began on January 27th; on December 15th the bridge was completed. The railroad bridge was renovated in and remains in operation today. The Dubuque Wagon Bridge opened in and was torn down in after the Julien Dubuque Bridge was completed in Julien Dubuque himself was an early Iowa pioneer, settling in what was then Spanish Louisiana in A fur-trader and lead-miner, Dubuque remained twenty years in northeastern Iowa, employing indigenous people and French Canadian settlers alike.
He was buried on the top of a bluff overlooking the Mississippi River near Dubuque [adapted from Fraser ]. The Julien Dubuque Bridge is a continuous steel-arch truss bridge with a suspended deck that traverses the Mississippi River. This bridge was named after Julien Dubuque, a French Canadian who arrived near what now is known as Dubuque, Iowa which is also named after him. Dubuque was one of the first white men to settle in the area. He initially received permission from the Fox Native American tribe to mine the lead in Subsequently, the Spanish confirmed that transaction by giving him a land grant in Once he had received permission from the Fox to mine lead, Julien Dubuque remained in the area for the rest of his life.
The Julien Dubuque Bridge is part of the U. It is one of two motor vehicle bridges over the Mississippi in the area the Dubuque-Wisconsin bridge is three miles north and links Dubuque with Wisconsin and is listed in the National Register of Historic Places.
According to the design specifications, the bridge superstructure was constructed with 1, tons of silicon steel and 2, tons of carbon steel. The approach spans used 3, tons of steel. The substructure required 34, cubic yards of concrete, 1, tons of steel and 2, timber piles.
Its longest span is feet, total length 5, feet and width 28 feet. The clearance below the bridge is 64 feet. When built, the foot main span was the second longest over the Mississippi River, fourth longest in the United States and eighth longest in the world. In , the first parts of the bridge were begun. In , the bridge was completed. The bridge was originally painted gray to help camouflage the bridge in case of enemy attack.
It was later repainted a dark green color and stayed that way until the early 's, when it was returned to its historic gray color during a renovation. Because the bridge was financed with bonds, it was initially operated as a toll bridge. Proceeds were used to help pay off the bonds. In the post-war years, traffic was so heavy that the bonds were paid off 11 years early, and the bridge became toll-free in In the early s, the bridge underwent an extensive renovation. The deck was completely replaced, and a new walkway installed on the bridge.
Due to congestion on the bridge, the Iowa DOT has developed preliminary plans to build a parallel, two-lane bridge directly to the south of the Julien Dubuque Bridge.
Some federal funding has been secured and right of way has been acquired. Construction is contingent upon additional federal funding being received. Coordinates Latitude, Longitude : Copy Coordinates.
0コメント