A tied-arch bridge is an arch bridge in which the outward-directed horizontal forces of the arch(es) are borne as tension by a chord tying the arch ends rather than by the ground or the bridge foundations. This strengthened chord may be the deck structure itself or consist of separate, independent tie-rods.
54-538: The Hernando de Soto Bridge is a tied-arch bridge carrying Interstate 40 across the Mississippi River between West Memphis, Arkansas , and Memphis , Tennessee . The design is a continuous cantilevered cable-stayed steel through arch, with bedstead endposts. Memphians also call the bridge the "New Bridge", as it is newer than the Memphis & Arkansas Bridge (carrying Interstate 55 ) downstream, and
108-463: A 90-degree change in I-55's direction onto the bridge, have led to more recent traffic problems including a failed TDOT plan that would have required a long-term closure of I-55 and the bridge in order to reconstruct the interchange, as well as lane closures and other issues at the interchange during the 2021 I-40 bridge closure during which this was the only open bridge at Memphis. On August 12, 2012,
162-434: A bridge pier on the approach bridge west of the river had settled overnight, and the bridge was subsequently closed to perform a precautionary inspection. The bridge was reopened later that day. Between 2000 and 2015, the bridge underwent a seismic retrofitting project, allowing it to withstand a 7.7 magnitude earthquake, the similar magnitude of earthquakes during the 1811–12 New Madrid earthquakes . The retrofit project
216-520: A cyclist was killed after being struck by a vehicle when using the shoulder approaching the bridge. On December 23, 2014, numerous news sources reported that the FBI had released an official statement warning local law enforcements of a threat to the bridge during that month. The FBI stated, "according to an anonymous complainant... ISIS instructed an ISIS member, a presumed USPER (U.S. person) in Memphis, with
270-580: A direct order to blow up the Memphis–Arkansas bridge on an unknown date, activating ISIS terror cells in the United States." Security was heightened, but the threat was later discredited. The need to eventually replace the Memphis & Arkansas Bridge has been recognized for some time, due to its age and the fact that it was not designed to withstand a high magnitude earthquake, as well as its violations of Interstate Highway standards. The need for
324-524: A fracture control plan. [....] • Other hydrogen cracks were identified on the interior tie girder surface at similar thickness transitions throughout the bridge. These hydrogen cracks were comparatively shallow (<3/16 in.), and those observed cracks tended to travel as intergranular cracks through the GCHAZ [grain coarsened heat affected zone] until they arrested in material with lower hardness and greater toughness and hydrogen tolerance. [....] • Given
378-466: A grant under the BIP to replace the Memphis & Arkansas Bridge. Under the terms of the application, TDOT and ARDOT have agreed to each pay for 25% of the total cost of the bridge, which is tentatively expected to cost $ 787.5 million, although the final figure could be higher. On July 12, 2024, a $ 394 million grant was awarded for the replacement. This project, which has been named "America's River Crossing",
432-504: A much larger share of the cost due to Tennessee's larger population. Both states eventually agreed to a compromise where Tennessee funded 60% of the cost and Arkansas the remaining 40%. Both states also initially disagreed on the design of the bridge; the original design called for longer through arches and a lower vertical clearance. Construction of the Hernando de Soto Bridge began on May 2, 1967. Initially planned for completion in 1971,
486-756: A new bridge was once again thrust into the spotlight when the Hernando de Soto Bridge was closed to all traffic between May 11 and August 2, 2021, due to a fracture in the structure. This forced much of the traffic on I-40 to detour across the Memphis & Arkansas Bridge. Later that year, the Infrastructure Investment and Jobs Act (IIJA) was enacted by Congress. This legislation includes the Bridge Investment Program (BIP), which provides $ 7.25 billion in federal funding until 2026 for bridge projects costing over $ 100 million. These projects are awarded in competitive grants at 50% of
540-427: A remote switch to toggle the lights on and off briefly while the vessel passes under the bridge. During the 2011 Mississippi River floods , the bridge became dark for about 2 months because the transformers that supply the electricity for the lights were removed to prevent damage to them by flood waters. The bridge was re-lit in a ceremony which occurred on June 21, 2011. On August 23, 2007, an inspector discovered that
594-529: A single span, two tied-arches are placed in parallel alongside the deck, so the deck lies in between the arches. Axial tied-arch or single tied-arch bridges have at most one tied-arch per span that is usually centered in the middle of the bridge deck. An example for this is Hoge Brug in Maastricht. Since it has hinged hangers it might also classify as a Nielsen bridge who held a patent on tied-arch bridges with hinged hangers from 1926. Some designs tilt
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#1732790992467648-410: A tied-arch bridge deck are translated, as tension, by vertical ties between the deck and the arch, tending to flatten it and thereby to push its tips outward into the abutments, like for other arch bridges. However, in a tied-arch or bowstring bridge, these movements are restrained not by the abutments but by the strengthened chord, which ties these tips together, taking the thrusts as tension, rather like
702-536: A tied-arch; however, the bowstring truss behaves as truss , not an arch . The visual distinction is a tied-arch bridge will not have substantial diagonal members between the vertical members. In a 1978 advisory issued by the Federal Highway Administration (FHWA), the FHWA noted that tied-arch bridges are susceptible to problems caused by poor welds at the connection between the arch rib and
756-520: Is also a means to protect the bridge as it is located within 100 miles (161 km) of the New Madrid Seismic Zone and serves as a major cargo route and traffic thoroughfare across the river. As part of this project, the main span, approaches, and ramps for the downtown exit were retrofitted. A bridge about 1 mile (1.6 km) west of the main span was rebuilt with earthquake considerations in mind. The federal government covered 80% of
810-626: Is tentatively planned to begin in 2026. Annual average daily traffic (AADT) figures reported by the Tennessee Department of Transportation for 2018, three years before the notable 2021 closure of the I-40 Hernando de Soto Bridge or "new bridge", show that the I-55 "old bridge" carries substantially more vehicles (64,520) than the I-40 bridge (37,308) despite its being older and narrower. Meanwhile, similar figures reported by
864-655: Is the Fremont Bridge in Portland, Oregon which is the second-longest tied-arch bridge in the world and also classifies as a through arch bridge . The Chaotianmen Bridge in Chongqing is a tied-arch, through arch and a truss arch bridge . Contrarily, the Hart Bridge uses a cantilevered trussed arch, it is self-anchored , but its arch is non-tied. In particular the bridge deck is suspended, but does not tie
918-479: The Arkansas Department of Transportation for 2020, the year before the I-40 bridge closure, from devices that also measure percentage of truck traffic suggest that though the I-40 bridge had slightly more vehicles (47,000) than the I-55 bridge (45,000), the I-55 bridge actually had a higher percentage of truck traffic (37 percent) than the I-40 bridge (26 percent). The bridge can be seen in scenes of
972-547: The Arkansas Department of Transportation , of the original wooden viaduct leading from West Memphis to the Harahan Bridge. Most of the 1930 viaduct was reused for the Memphis & Arkansas Bridge until the present I-55 viaduct replaced it in the 1980's; a small portion of that viaduct now serves as the Arkansas entrance to the Harahan Bridge's Big River Crossing (built on one of its former "wagonways"). Planning for
1026-604: The Fremont Bridge in Portland, Oregon and the first "computer-designed" bridge of this type, the Fort Pitt Bridge in Pittsburgh, Pennsylvania . Both the tied-arch bridge and the self-anchored suspension bridge place only vertical loads on the anchorage, and so are suitable where large horizontal forces are difficult to anchor. Some tied-arch bridges only tie a segment of the main arch directly and prolong
1080-844: The Memphis–Arkansas Bridge or inaccurately as the Memphis–Arkansas Memorial Bridge , is a cantilevered through truss bridge carrying Interstate 55 across the Mississippi River between West Memphis, Arkansas and Memphis, Tennessee . Memphians refer to this bridge as the "Old Bridge" to distinguish it from the "New Bridge", or Hernando de Soto Bridge , upstream. The Memphis & Arkansas Bridge also carries U.S. Route 61 (US 61), US 64 , US 70 , US 78 , and US 79 from Memphis to West Memphis; it also carried US 63 prior to its truncation (and later rerouting) in Arkansas. The western terminus of Tennessee State Route 1 (SR 1) sits on
1134-497: The " M Bridge ", due to its distinctive shape. It is of similar construction to the Sherman Minton Bridge between Louisville, Kentucky , and New Albany, Indiana (except that it consists of a single level deck). Preliminary planning for the river crossing began in 1960 as part of Interstate 40 alignment studies for the Memphis - Little Rock corridor, which was constructed in segments between 1963 and 1968. Before
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#17327909924671188-471: The 48-year service life of this structure, the fact that the subject fracture occurred in three separate phases over several years, the recent inspection efforts to identify welding defects at the tie girder thickness transition welds, and no evidence of observed fatigue crack growth during this study, it is highly unlikely that an additional major fracture of a similar tie girder thickness transition weld will occur. Tied-arch bridge Thrusts downwards on
1242-492: The Harahan Bridge and display various color patterns dependent upon special occasions or requests. Both displays have been created under an initiative called "Mighty Lights." The $ 14 million privately funded project was completed in 2018. On May 11, 2021, an inspection discovered a partially fractured tie girder on the Span A North truss. Two of the four plates comprising the box-shaped tension tie member were completely fractured and
1296-577: The Hernando de Soto Bridge was completed, traffic going across the river was carried across the Mississippi River by the Interstate 55/US Highway 64/70/79/61 Memphis & Arkansas Bridge crossing, located 2 miles (3.2 km) southwest. The two states initially feuded over the cost of paying for the bridge. Tennessee officials believed that both states should equally pay for the bridge, while Arkansas officials wanted Tennessee to shoulder
1350-403: The Mississippi River and died south of Memphis. At night, the bridge was illuminated by 200 sodium vapor lights along its "M" structure. The bridge was first illuminated on September 5, 1986, after $ 373,000 of private funds had been raised to fund the cost and installation of the lights. Due to some river traffic having issues with the lights at night reflecting on the water, the city installed
1404-558: The Tennessee side, but give way to grassy slopes on the shoulders of I-55 on the Arkansas side. The sidewalk and bridge is listed as part of the Mississippi River Trail . However, travel is not recommended across the sidewalk and is prohibited on the vehicle traffic lanes of the bridge, as the structure is an Interstate Highway crossing. In 2016, a pedestrian/bicycle path on the neighboring Harahan Bridge made crossing
1458-544: The Tennessee–Arkansas boundary halfway across the bridge. Opened in 1949, the bridge is currently the oldest bridge on the Interstate Highway System in Tennessee and Arkansas. It is currently planned to be replaced with a larger and wider bridge, starting in 2026. The bridge consists of five Warren through trusses, each with a length of 790 feet (240 m). Combined with the approach segments,
1512-692: The arch ends. Tied arch bridges may consist of successively lined up tied arches in places where a single span is not sufficient. An example for this is the Godavari Arch Bridge in Rajahmundry, India. It has four separate supports on each pier and carries the South Central Railway Line of India. It was designed for 250 km/h rail services. Like for multi-span continuous beam bridges the tying chord continually spans over all piers. The arches feet coincide (fuse) at
1566-413: The arches outward or inward with respect to the axis running along the bridge deck. In analogy to twin bridges , two tied arch bridges erected side by side to increase traffic capacity, but structurally independent, may be referred to by tied arch twin bridges . Each in return may use a single- or multi-span, discrete or continuous tied-arch design. A bowstring truss bridge is similar in appearance to
1620-413: The arches. Contrarily each abutment on the riverbanks supports a single arch end only, in the middle of the deck. The tying chord(s) consist of a composite deck structure. Four post tensioned coil steel cables, two to each side of the walking deck, are locked in place by orthogonally run steel beams every 7.5 meters. The hangers are joined to each of these beams between each cable pair. Since the beams extend
1674-439: The bottom plate was partially fractured, leaving only the inside-facing plate intact. Since the severely compromised girder was one of a pair of load-bearing tension members that were critical to the structural integrity of the bridge's tied-arch design, the bridge was structurally unsound and at risk of collapse. The inspecting engineer called 9-1-1 and told authorities to shut down the bridge immediately. Vehicular traffic across
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1728-420: The bridge and river traffic under the bridge were halted while engineers inspected the entire bridge for other issues, and analyzed the structure. River traffic under the bridge resumed three days later on May 14. Initial repairs that affixed steel plates on both sides of the affected girder were completed on May 25. The second phase consisted of the installation of additional steel plating and removal of part of
1782-463: The bridge piers. A good visual indication are shared supports at the piers. Dynamic loads are distributed between spans. This type may be combined with the shouldered tied-arch design discussed above. An example for this is Dashengguan Bridge in Nanjing, China. Its two main arches are shouldered by short auxiliary arches. It is both, a (rigid) tied-arch and a cantilevered trussed arch design. Because
1836-578: The bridge's total length is 5,222 feet (1,592 m). Completed in 1949, it is the only bridge spanning the Mississippi River designed to carry exclusively vehicular traffic that was built before 1950. It was designed by Modjeski and Masters, successors to the firm that designed the Harahan Bridge , built in 1916 to carry vehicular and rail traffic. The bridge was listed on the National Register of Historic Places in 2001. Built before
1890-644: The cost, with Tennessee contributing 12% and Arkansas 8%. It was announced after the opening of the Big River Crossing along the Harahan Bridge to the south that the existing sodium vapor lights along the Hernando Desoto Bridge would be replaced with a new LED lighting display, thus making the Hernando de Soto Bridge the second bridge over the Mississippi River to be lit as such after the Harahan. The new display can be lit in sync with
1944-535: The damaged beam. A new inspection of the bridge found "nothing of concern". The eastbound lanes reopened on July 31, 2021, the westbound lanes on August 2, 2021. During the closure, vehicle traffic utilized the nearby Memphis & Arkansas Bridge ( I-55 ) as an alternate route in the Memphis area, as well as the Caruthersville Bridge ( I-155 ) to the north and the Helena Bridge ( US 49 ) to
1998-454: The established navigation channel beneath them. Construction on the bridge began on September 12, 1945, and the bridge opened to traffic on December 17, 1949. Though Crump Boulevard was originally intended to serve as the main access to the bridge from Memphis, TDOT replaced the west end of Crump Boulevard with a stretch of I-55 in the late 1960's. The issues resulting from the cloverleaf interchange at I-55 and Crump, required to accommodate
2052-419: The firm founded by Ralph Modjeski who designed the Harahan Bridge in 1916 and helped design the area's original Frisco Bridge in 1892, to prepare plans for this bridge even though Modjeski himself died in 1940. Though truss bridges increasingly fell out of fashion after World War II , this bridge's truss design, especially its main span, was largely dictated by the neighboring Frisco & Harahan Bridges and
2106-459: The introduction of the Interstate Highway System , the span was not built to Interstate Highway standards ; it originally lacked the concrete barrier between the different directions of traffic which, was added later. It was also built with a sidewalk on either side of the roadway, positioned just outside the steel truss girders. The sidewalks, now also separated from the traffic lanes by concrete barriers, are accessible from Memphis city sidewalks on
2160-503: The mandated hands-on—that is, within arm's length—inspections that should have occurred every two years had not been undertaken. The responsible inspector was subsequently fired. An engineering analysis revealed the fracture was the result of two particularly wide and poorly done weld repairs in the same spot during "fabrication" (construction) that, along with other poor welds elsewhere on the bridge, had been identified and repaired; there were consequently no further concerns. Key findings of
2214-515: The new bridge began in 1939 with the creation of a joint Memphis-Arkansas bridge commission headed by longtime Memphis political boss E. H. Crump . Walter Chandler , another notable Tennessee politician who was a member of the Crump machine at that time, also served on the bridge commission. Simultaneously with the bridge, Crump planned a new bypass street leading to the bridge, avoiding both downtown Memphis and historic African American neighborhoods to
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2268-465: The project experienced multiple delays. The double-arch bridge was opened to automobile traffic on August 2, 1973. A dedication ceremony for the bridge occurred on August 17, 1973. Initially expected to be only $ 12 million (equivalent to $ 80.3 million in 2024), the final price tag was approximately $ 57 million (equivalent to $ 299 million in 2024). The bridge is named for 16th century Spanish explorer Hernando de Soto , who explored this stretch of
2322-501: The report included the following four points: • Metallographic examination of the fracture surfaces identified two weld repairs from fabrication that were much wider and contained weld metal deposit sequencing that differed from other side plate thickness transition welds in the bridge. • The weld repairs caused two large hydrogen cracks as a result of the inherent restraint, improper preheat and/or use of contaminated welding electrodes commonly associated with weld repairs performed without
2376-469: The river safer and eliminated the need to use the I-55 bridge. Despite common references to this bridge as a "Memorial Bridge", most likely resulting from its opening shortly after World War II, there is no evidence that this bridge was ever intended to be a memorial to anything. There is no mention of any memorial intent on the bridge's nameplates, including a dedicatory poem on one nameplate (officially attributed to Walter Chandler) that appears to focus on
2430-560: The single-lane cantilevered "wagonways" of the Harahan Bridge from its opening in 1916 all the way to this bridge's opening in 1949. This increased traffic led to the incorporation of West Memphis, Arkansas in 1927 where the Arkansas roadways leading to the Harahan Bridge came together, as well as the 1930 replacement by the Arkansas State Highway Commission (ASHC), the modern-day version of which oversees
2484-479: The south as alternates elsewhere in the Mid-South. Investigators received amateur photos taken from the river below as early as 2016 that already showed damage at the same site. And according to the Arkansas Department of Transportation , review of archived drone footage taken during a May 2019 bridge inspection, two years before the damage was discovered, also showed the fracture. The department further found that
2538-512: The south, which came to be known as Crump Boulevard. Aretha Franklin was born on Lucy Avenue, in just such a neighborhood south of Crump Boulevard, in 1942 before moving eventually to Detroit where she became famous as the Queen of Soul. By May 1944, the ASHC and Tennessee's Department of Highway and Public Works (now the Tennessee Department of Transportation or TDOT) hired Modjeski and Masters,
2592-467: The strengthened chord to tie to the top ends of auxiliary (half-)arches . The latter usually support the deck from below and join their bottom feet to those of the main arch(es). The supporting piers at this point may be slender, because the outward-directed horizontal forces of main and auxiliary arch ends counterbalance. The whole structure is self-anchored . Like the simple case it exclusively places vertical loads on all ground-bound supports. An example
2646-578: The string of a bow that is being flattened. Therefore, the design is also called a bowstring-arch or bowstring-girder bridge . The elimination of horizontal forces at the abutments allows tied-arch bridges to be constructed with less robust foundations; thus they can be situated atop elevated piers or in areas of unstable soil . In addition, since they do not depend on horizontal compression forces for their integrity, tied-arch bridges can be prefabricated offsite, and subsequently floated, hauled or lifted into place. Notable bridges of this type include
2700-469: The tie girders, and at the connection between the arch and vertical ties. In addition, problems with electroslag welds , while not isolated to tied-arch bridges, resulted in costly, time-consuming and inconveniencing repairs. The structure as a whole was described as nonredundant : failure of either of the two tie girders would result in failure of the entire structure. Memphis %26 Arkansas Bridge The Memphis & Arkansas Bridge , also known as
2754-539: The total cost. On April 17, 2023, Governor Bill Lee signed into law the Transportation Modernization Act, which provides increased funding for highway projects in Tennessee. Six months later TDOT and ARDOT completed a study on the possibility of a new bridge in Memphis, which found that replacing the Memphis & Arkansas bridge would be the most cost-effective option. On December 4, 2023, TDOT and ARDOT jointly submitted an application for
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#17327909924672808-428: The traffic expected to cross the bridge rather than any memorial. (This is in contrast to the Harahan Bridge, which was named for a railroad executive who died in an accident during the bridge's construction.) Crump himself, for whom the boulevard originally leading to the bridge was named, lived until 1954; Chandler lived until 1967. The Memphis & Arkansas Bridge was inspired by the ever increasing flow of traffic on
2862-477: The traffic runs through the structural envelope, it is also a through arch bridge. Guandu Bridge in New Taipei, Taiwan is a non-trussed example with three main arches augmented by two auxiliary arch segments at the bridge portals. The Infinity Bridge uses two arches of different height and span length that both bifurcate before their apex. Above its single, middle-displaced river pier the deck lies between
2916-474: The width of the post-tensioned concrete deck, the tensing cable pairs remain visible. A close-up of the river pier shows that the structural dead load is tied per span: The larger arch span uses thicker tensing cables and the reflex segments are not suspended from, but supported by steel beams, essentially completing the arches at the river pier. However, for dynamic and non-uniform loads the visually defining arch continuations must not be neglected. Usually, for
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