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22-657: The Sunshine Bridge is a cantilever bridge over the Mississippi River in St. James Parish, Louisiana . Completed in 1963, it carries Louisiana Highway 70 (LA70), which connects Donaldsonville on the west bank of Ascension Parish with Sorrento on the east bank of Ascension Parish as well as with Gonzales on the east bank of Ascension Parish. The approach roads on the east and west banks begin in Ascension Parish before crossing into St. James Parish. The bridge

44-423: A balanced cantilever ; when they attach to a solid foundation, the counterbalancing arms are called anchor arms . Thus, in a bridge built on two foundation piers, there are four cantilever arms: two which span the obstacle, and two anchor arms that extend away from the obstacle. Because of the need for more strength at the balanced cantilever's supports, the bridge superstructure often takes the form of towers above

66-505: A bridge that could handle differential settlement of the foundations. Engineers could more easily calculate the forces and stresses with a hinge in the girder. Heinrich Gerber was one of the engineers to obtain a patent for a hinged girder (1866) and is recognized as the first to build one. The Hassfurt Bridge over the Main river in Germany with a central span of 124 feet (38 metres)

88-448: A fixed axis of rotation , with all other translations or rotations prevented; thus a hinge has one degree of freedom . Hinges may be made of flexible material or moving components. In biology , many joints function as hinges, such as the elbow joint. Ancient remains of stone, marble, wood, and bronze hinges have been found. Some date back to at least Ancient Egypt , although it is nearly impossible pinpoint exactly where and when

110-583: Is a convenient river crossing for residents of Baton Rouge, Hammond , and the Florida Parishes to travel to the Bayou cities of Morgan City , Houma and Thibodaux as well as vice versa. The bridge plays an important role in storm evacuation and in industrial development along the Mississippi. From its opening in 1964 through August 15, 2001, a 50-cent toll was collected on traffic crossing to

132-438: Is available to support the tension in the upper chord of the span during construction, usually limiting this method to the spanning of narrow canyons. World's longest cantilever bridges (by longest span): Hinge A hinge is a mechanical bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about

154-542: The Gravina Island Bridge , the Sunshine Bridge was placed into the same category. While the only bridge across the Mississippi between New Orleans and Baton Rouge when it opened for traffic in 1964, its south end then emptied into a swamp, and for years it awaited funding to connect it to LA 70 and other roads. When this occurred, the economy in this area grew by leaps and bounds, largely due to

176-465: The Navajo Bridge ) are built using pure cantilever spans from each side, with neither falsework below nor temporary supporting towers and cables above. These are then joined with a pin, usually after forcing the union point apart, and when jacks are removed and the bridge decking is added the bridge becomes a truss arch bridge . Such unsupported construction is only possible where appropriate rock

198-435: The 19th century understood that a bridge that was continuous across multiple supports would distribute the loads among them. This would result in lower stresses in the girder or truss and meant that longer spans could be built. Several 19th-century engineers patented continuous bridges with hinge points mid-span. The use of a hinge in the multi-span system presented the advantages of a statically determinate system and of

220-415: The action of the outer foundations. Cantilever Bridge.—A structure at least one portion of which acts as an anchorage for sustaining another portion which extends beyond the supporting pier. A simple cantilever span is formed by two cantilever arms extending from opposite sides of an obstacle to be crossed, meeting at the center. In a common variant, the suspended span , the cantilever arms do not meet in

242-603: The bridge was planned to be fully reopened in August. The loss of this Mississippi River crossing meant that traffic was required to take a significant detour to either the Gramercy Bridge or the Horace Wilkinson Bridge , a detour that was at least 10 miles (16 km) in length. Extensive signage warning motorists of the bridge closure well in advance was erected on each side, including detour signs at

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264-423: The center; instead, they support a central truss bridge which rests on the ends of the cantilever arms. The suspended span may be built off-site and lifted into place, or constructed in place using special travelling supports. A common way to construct steel truss and prestressed concrete cantilever spans is to counterbalance each cantilever arm with another cantilever arm projecting the opposite direction, forming

286-707: The first hinges were used. In Ancient Rome , hinges were called cardō and gave name to the goddess Cardea and the main street Cardo . This name cardō lives on figuratively today as "the chief thing (on which something turns or depends)" in words such as cardinal . According to the OED , the English word hinge is related to hang . Other types of hinges include: Since at least medieval times, there have been hinges to draw bridges for defensive purposes for fortified buildings. Hinges are used in contemporary architecture where building settlement can be expected over

308-648: The foundation piers. The Commodore Barry Bridge is an example of this type of cantilever bridge. Steel truss cantilevers support loads by tension of the upper members and compression of the lower ones. Commonly, the structure distributes the tension via the anchor arms to the outermost supports, while the compression is carried to the foundations beneath the central towers. Many truss cantilever bridges use pinned joints and are therefore statically determinate with no members carrying mixed loads. Prestressed concrete balanced cantilever bridges are often built using segmental construction . Some steel arch bridges (such as

330-457: The improved transportation. Much of the criticism involved residual resentment from the bridge being named to recognize Governor Jimmie Davis . Built under his administration, Davis had twice picked and sung his way into the Governor's Mansion with hits like " You Are My Sunshine " and whose horse, which he rode into the Governor's office at his second inaugural, was also named Sunshine. On

352-433: The interchange of Interstate 10 and LA 22 , which connects to LA 70 some five miles (8.0 km) north of the bridge. Cantilever bridge The steel truss cantilever bridge was a major engineering breakthrough when first put into practice, as it can span distances of over 1,500 feet (450 m), and can be more easily constructed at difficult crossings by virtue of using little or no falsework . Engineers in

374-540: The life of the building. For example, the Dakin Building in Brisbane , California , was designed with its entrance ramp on a large hinge to allow settlement of the building built on piles over bay mud . This device was effective until October 2006, when it was replaced due to damage and excessive ramp slope. Hinges appear in large structures such as elevated freeway and railroad viaducts, to reduce or eliminate

396-577: The morning of October 12, 2018, a crane being transported on a barge operated by Marquette Transportation collided with The Sunshine Bridge. The crane was reportedly being transported while its boom was still in an upright position. Due to extensive damage done to a main load carrying span, the Sunshine Bridge was immediately closed to all vehicle traffic for emergency repairs. These repairs were expected to be completed in late January or early February 2019. The eastbound lanes were projected to reopen in April, and

418-431: The structural principles of the suspended span cantilever by sitting in chairs and supporting their colleague, Kaichi Watanabe , in between them, using just their arms and wooden poles. The suspended span, where Watanabe sits, is in the center. The wooden poles resist the compression of the lower chord , while the outstretched arms support the tension of the upper chord. The placement of the brick counterweights demonstrates

440-807: The west bank. The toll was discontinued by an act of the Louisiana Legislature , authored by Louisiana State Representative Roy Quezaire (D-Donaldsonville), whose district included the bridge. The bridge gained national attention in 2008 when it became part of the Bridge to Nowhere controversy which arose during the US Presidential Election . Focused primarily on the Alaskan Governor/Vice Presidential Candidate Sarah Palin's efforts to secure federal funding for

462-574: Was 275 feet (84 metres) deep and took full advantage of the fact that falsework, or temporary support, is not needed for the main span of a cantilever bridge. The Forth Bridge is a notable example of an early cantilever bridge. This bridge held the record for longest span in the world for twenty-nine years until it was surpassed by the Quebec Bridge . The engineers responsible for the bridge, Sir Benjamin Baker and Sir John Fowler , demonstrated

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484-550: Was completed in 1867 and is recognized as the first modern cantilever bridge. The High Bridge of Kentucky by C. Shaler Smith (1877), the Niagara Cantilever Bridge by Charles Conrad Schneider (1883) and the Poughkeepsie Bridge by John Francis O'Rourke and Pomeroy P. Dickinson (1889) were all important early uses of the cantilever design. The Kentucky River Bridge spanned a gorge that

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