63-503: The Waldo–Hancock Bridge was the first long-span suspension bridge erected in Maine , as well as the first permanent bridge across the Penobscot River downstream from Bangor . The name comes from connecting Waldo and Hancock counties. The bridge was built in 1931 and retired in 2006, when the new Penobscot Narrows Bridge was opened just a few yards away. Demolition of the structure
126-410: A cable-stayed bridge in which the deck is in compression. Cable-stayed bridges and suspension bridges may appear to be similar, but are quite different in principle and in their construction. In suspension bridges, large main cables (normally two) hang between the towers and are anchored at each end to the ground. The main cables, which are free to move on bearings in the towers, bear the load of
189-521: A suicide barrier on the bridge. This proposal was rejected due to cost, as a barrier was estimated to cost between $ 500,000 and $ 1 million, plus additional costs for regular inspections. As an alternative, two solar-powered phones were installed on each end of the bridge in May 2015 which connect users to a suicide hotline. The phones cost $ 30,000. State officials were aware of instances the phones were not functional, and increased inspections of them to weekly from
252-456: A 200 feet span (also termed Beose Bridge) was constructed near Sagar, India during 1828–1830 by Duncan Presgrave, Mint and Assay Master. The Clifton Suspension Bridge (designed in 1831, completed in 1864 with a 214 m central span), is similar to the Sagar bridge. It is one of the longest of the parabolic arc chain type. The current Marlow suspension bridge was designed by William Tierney Clark and
315-492: A bridge has a tendency to collapse simply because of the gravitational forces acting on the materials of which the bridge is made. Live load refers to traffic that moves across the bridge as well as normal environmental factors such as changes in temperature, precipitation, and winds. Dynamic load refers to environmental factors that go beyond normal weather conditions, factors such as sudden gusts of wind and earthquakes. All three factors must be taken into consideration when building
378-468: A bridge. Silver Bridge (USA) was an eyebar chain highway bridge, built in 1928, that collapsed in late 1967, killing forty-six people. The bridge had a low-redundancy design that was difficult to inspect. The collapse inspired legislation to ensure that older bridges were regularly inspected and maintained. Following the collapse a bridge of similar design was immediately closed and eventually demolished. A second similarly-designed bridge had been built with
441-757: A bridge. The principles of suspension used on a large scale also appear in contexts less dramatic than road or rail bridges. Light cable suspension may prove less expensive and seem more elegant for a cycle or footbridge than strong girder supports. An example of this is the Nescio Bridge in the Netherlands, and the Roebling designed 1904 Riegelsville suspension pedestrian bridge across the Delaware River in Pennsylvania. The longest pedestrian suspension bridge, which spans
504-737: A first in the United States. Monitoring on the strands will evaluate this material for future use in bridge designs. These engineering innovations helped the bridge appear in the December 2006 edition of Popular Science as one of the 100 best innovations of the year. The total project cost was $ 85 million. The bridge was designed as an emergency replacement for the Waldo–Hancock Bridge. Just 42 months elapsed from conception to completion. A unique project delivery method, referred to as "owner facilitated design/build", partnered Maine DOT with FIGG as
567-403: A higher margin of safety and remained in service until 1991. The Tacoma Narrows Bridge , (USA), 1940, was vulnerable to structural vibration in sustained and moderately strong winds due to its plate-girder deck structure. Wind caused a phenomenon called aeroelastic fluttering that led to its collapse only months after completion. The collapse was captured on film. There were no human deaths in
630-507: A pedestrian suspension bridge over the Machchhu River in the city of Morbi, Gujarat, India collapsed, leading to the deaths of at least 141 people. Penobscot Narrows Bridge The Penobscot Narrows Bridge is a 2,120-foot-long (650 m) cable-stayed bridge that carries US 1 / SR 3 over the Penobscot River . It connects Verona Island to Prospect , in the U.S. state of Maine . It opened in December 2006, replacing
693-641: A proposal by Robert Stevenson for a bridge over the River Almond near Edinburgh . Roebling's Delaware Aqueduct (begun 1847) consists of three sections supported by cables. The timber structure essentially hides the cables; and from a quick view, it is not immediately apparent that it is even a suspension bridge. The main suspension cables in older bridges were often made from a chain or linked bars, but modern bridge cables are made from multiple strands of wire. This not only adds strength but improves reliability (often called redundancy in engineering terms) because
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#1733084685696756-492: A sequence generally described as follows. Depending on length and size, construction may take anywhere between a year and a half (construction on the original Tacoma Narrows Bridge took only 19 months) up to as long as a decade (the Akashi-Kaikyō Bridge's construction began in May 1986 and was opened in May 1998 – a total of twelve years). Suspension bridges are typically ranked by the length of their main span. These are
819-499: A temporary walkway. Poured sockets are used to make a high strength, permanent cable termination. They are created by inserting the suspender wire rope (at the bridge deck supports) into the narrow end of a conical cavity which is oriented in-line with the intended direction of strain. The individual wires are splayed out inside the cone or 'capel', and the cone is then filled with molten lead-antimony-tin (Pb80Sb15Sn5) solder. Most suspension bridges have open truss structures to support
882-627: Is considered the last remaining Inca rope bridge and is rebuilt annually. The first iron chain suspension bridge in the Western world was the Jacob's Creek Bridge (1801) in Westmoreland County, Pennsylvania , designed by inventor James Finley . Finley's bridge was the first to incorporate all of the necessary components of a modern suspension bridge, including a suspended deck which hung by trusses. Finley patented his design in 1808, and published it in
945-465: Is located in the 420-foot (128 m) west tower, allowing visitors to view the bridge, the nearby Fort Knox State Historic Site , the Penobscot River , and Penobscot Bay . The Penobscot Narrows Observatory opened to the general public on May 19, 2007. It is open at the same times of the year as Fort Knox (May 1 to October 31). The elevator has had a series of technical problems, including one on July 1, 2014, when 13 people were temporarily stuck in
1008-797: The Mahakam River , located in Kutai Kartanegara Regency , East Kalimantan district on the Indonesia island of Borneo , was built in 1995, completed in 2001 and collapsed in 2011. Dozens of vehicles on the bridge fell into the Mahakam River . As a result of this incident, 24 people died and dozens of others were injured and were treated at the Aji Muhammad Parikesit Regional Hospital. Meanwhile, 12 people were reported missing, 31 people were seriously injured, and 8 people had minor injuries. Research findings indicate that
1071-631: The Shortnose sturgeon . Barges were placed in the Penobscot River onto which sections of the bridge were lowered. The concrete piers in the river are all that remains, and MDOT worked with the United States Coast Guard to design lights for them once the Bridge was removed to aid ships in the river. Later, MaineDOT announced that the low bid of $ 5.35 million by S&R Corp. of Lowell, Massachusetts,
1134-709: The Waldo–Hancock Bridge , built in 1931. The Penobscot Narrows Bridge is one of three bridges in the US (the others being the Zakim Bridge in Boston, Massachusetts , and the Veterans' Glass City Skyway in Toledo, Ohio ) constructed in the 2000s using a cradle system that carries the strands within the stays from bridge deck to bridge deck, as a continuous element, eliminating anchorages in
1197-537: The Maine legislature was reportedly planning to "pull together a study group on suicides by bridge." The bridge was closed for the first time on December 29, 2013, after ice chunks began falling from the support cables onto the bridge deck. The ice was present from a storm on December 22, but did not fall off until the 29th due to cold weather. Hancock County Sheriff's Deputies began receiving reports of damaged cars that morning and upon inspection recommended to MaineDOT that
1260-741: The Philadelphia journal, The Port Folio , in 1810. Early British chain bridges included the Dryburgh Abbey Bridge (1817) and 137 m Union Bridge (1820), with spans rapidly increasing to 176 m with the Menai Bridge (1826), "the first important modern suspension bridge". The first chain bridge on the German speaking territories was the Chain Bridge in Nuremberg . The Sagar Iron Suspension Bridge with
1323-542: The River Paiva, Arouca Geopark , Portugal, opened in April 2021. The 516 metres bridge hangs 175 meters above the river. Where such a bridge spans a gap between two buildings, there is no need to construct towers, as the buildings can anchor the cables. Cable suspension may also be augmented by the inherent stiffness of a structure that has much in common with a tubular bridge . Typical suspension bridges are constructed using
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#17330846856961386-559: The State Highway Commission, which enabled the construction of a second bridge between Verona Island and Bucksport. When opened in 1931 the bridge collected tolls used to retire the bonds issued to finance its construction. All tolls were lifted twenty-two years later on October 31, 1953, however, when those original construction bonds were paid off. Original tolls ranged from 10¢ for "one or two horse vehicle including driver" to 50¢ for "auto truck or tractor over 26,000 pounds". As
1449-657: The Waldo–Hancock Bridge represented a number of firsts. It was one of the first two bridges in the U.S. (along with the St. Johns Bridge in Portland, Oregon , completed in June 1931) to employ Robinson and Steinman's prestressed twisted wire strand cables, which were first used on the 1929 Grand Mère Suspension Bridge over the Saint-Maurice River in Quebec. The prefabrication and prestressing of
1512-453: The Waldo–Hancock Bridge was ceremoniously closed. Barricades were erected at both ends, closing the bridge to both cars and pedestrians. The Maine Department of Transportation announced on February 14, 2012, that the bridge would be demolished starting that summer and be completed by the fall. The schedule was designed to accommodate the needs of two endangered species, the Peregrine falcon and
1575-522: The bridge approached its seventieth anniversary with the end of the century, a series of routine safety inspections made by the Maine Department of Transportation revealed that over those seven decades the structure's two main suspension cables and the many vertical bridge deck stringers had become seriously corroded, thereby deteriorating their ability to support the deck, roadway and the traffic that crossed it. These engineering studies made it clear that
1638-435: The bridge be closed. At least five vehicles were damaged and two destroyed by the ice. While MaineDOT estimated that 70% of the ice had fallen by that afternoon, it was feared that reopening the bridge would shake more ice onto the bridge deck. MaineDOT also ruled out sending crews onto the bridge cables to remove the ice as too dangerous, but by the following day they were considering bringing in heavy equipment to knock ice off
1701-432: The bridge deck. Before the deck is installed, the cables are under tension from their own weight. Along the main cables smaller cables or rods connect to the bridge deck, which is lifted in sections. As this is done, the tension in the cables increases, as it does with the live load of traffic crossing the bridge. The tension on the main cables is transferred to the ground at the anchorages and by downwards compression on
1764-540: The bridge opened, MaineDOT was aware of many suicide attempts from the Waldo-Hancock Bridge and discussed possible pedestrian safety measures for the new bridge, but no special fencing or other action was taken. On February 26, 2014, in the wake of another suicide from the bridge, independent Rep. Joe Brooks of Winterport proposed emergency legislation to the Maine Legislature to require the installation of
1827-408: The bridge required immediate major rehabilitation and eventual replacement. Work was undertaken to rehabilitate the bridge starting in 2000 by Cianbro and Piasecki Steel Construction Corp. with cable work by Williamsport Wirerope Works Inc., by focusing on strengthening the cables. The two cables were done separately, one a time. Piasecki Steel Construction Corp. of Castleton, New York, rehabilitated
1890-513: The cables decreased the number of field adjustments required, saving considerable time, effort, and money. As an additional experiment in efficiency, the Waldo–Hancock cables were marked prior to construction, ensuring proper setting. This method had never been used before and proved successful in this instance. These innovations, invented and pioneered by Steinman, were a significant step forward for builders of suspension bridges. The Waldo–Hancock
1953-415: The cables more quickly. New concrete anchorages with up to 30-foot-long (9.1 m) anchor rods were built by Cianbro. Crews installed continuous runs of strands on new saddles bolted and welded on new base plates atop cable bents and the main towers. Workers placed two groups of four strands 12 feet (3.7 m) above each main cable to allow for pulls. Each strand weighs 4 tons (3.6 metric tons). A rope pull
Waldo–Hancock Bridge - Misplaced Pages Continue
2016-589: The cables. The bridge reopened on December 30, 2013, after being closed just one day but closed again January 5, 2014, for at least another day, "in anticipation that the ice would melt as temperatures moderated for the first time in days." The bridge was briefly closed on December 7, 2017, when a woman armed with a shotgun was seen walking across the bridge from the Prospect side to the Verona Island side and then sat on
2079-484: The chains are not attached to abutments as is usual, but instead are attached to the main girders, which are thus in compression. Here, the chains are made from flat wrought iron plates, eight inches (203 mm) wide by an inch and a half (38 mm) thick, rivetted together. The first wire-cable suspension bridge was the Spider Bridge at Falls of Schuylkill (1816), a modest and temporary footbridge built following
2142-574: The collapse of James Finley's nearby Chain Bridge at Falls of Schuylkill (1808). The footbridge's span was 124 m, although its deck was only 0.45 m wide. Development of wire-cable suspension bridges dates to the temporary simple suspension bridge at Annonay built by Marc Seguin and his brothers in 1822. It spanned only 18 m. The first permanent wire cable suspension bridge was Guillaume Henri Dufour 's Saint Antoine Bridge in Geneva of 1823, with two 40 m spans. The first with cables assembled in mid-air in
2205-519: The collapse was largely caused by the construction failure of the vertical hanging clamp. It was also found that poor maintenance, fatigue in the cable hanger construction materials, material quality, and bridge loads that exceed vehicle capacity, can also have an impact on bridge collapse. In 2013 the Kutai Kartanegara Bridge rebuilt the same location and completed in 2015 with a Through arch bridge design. On 30 October 2022, Jhulto Pul ,
2268-517: The collapse; several drivers escaped their cars on foot and reached the anchorages before the span dropped. Yarmouth suspension bridge (England) was built in 1829 and collapsed in 1845, killing 79 people. Peace River Suspension Bridge (Canada), which was completed in 1943, collapsed when the north anchor's soil support for the suspension bridge failed in October 1957. The entire bridge subsequently collapsed. Kutai Kartanegara Bridge (Indonesia) over
2331-417: The deck below, upon which traffic crosses. This arrangement allows the deck to be level or to arc upward for additional clearance. Like other suspension bridge types, this type often is constructed without the use of falsework . The suspension cables must be anchored at each end of the bridge, since any load applied to the bridge is transformed into tension in these main cables. The main cables continue beyond
2394-477: The designer and Cianbro /Reed & Reed LLC as the contractor. The elevator system in the tower, which is claimed to be the fastest and tallest elevator in Maine, was installed by Stanley Elevator Company, Inc. The Penobscot Bridge site is home to the Penobscot Narrows Observatory , the first bridge observation tower in the United States and the tallest public bridge observatory in the world. it
2457-418: The early 1800s. Simple suspension bridges , which lack vertical suspenders, have a long history in many mountainous parts of the world. Besides the bridge type most commonly called suspension bridges, covered in this article, there are other types of suspension bridges . The type covered here has cables suspended between towers , with vertical suspender cables that transfer the live and dead loads of
2520-571: The failure of a few flawed strands in the hundreds used pose very little threat of failure, whereas a single bad link or eyebar can cause failure of an entire bridge. (The failure of a single eyebar was found to be the cause of the collapse of the Silver Bridge over the Ohio River .) Another reason is that as spans increased, engineers were unable to lift larger chains into position, whereas wire strand cables can be formulated one by one in mid-air from
2583-432: The highway, which may be supported by suspender cables or their own trusswork . In cases where trusswork supports the spans, there will be very little arc in the outboard main cables. The earliest suspension bridges were ropes slung across a chasm, with a deck possibly at the same level or hung below the ropes such that the rope had a catenary shape. The Tibetan siddha and bridge-builder Thangtong Gyalpo originated
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2646-530: The live loads. In an underspanned suspension bridge, also called under-deck cable-stayed bridge, the main cables hang entirely below the bridge deck, but are still anchored into the ground in a similar way to the conventional type. Very few bridges of this nature have been built, as the deck is inherently less stable than when suspended below the cables. Examples include the Pont des Bergues of 1834 designed by Guillaume Henri Dufour ; James Smith's Micklewood Bridge; and
2709-628: The modern method was Joseph Chaley 's Grand Pont Suspendu in Fribourg , in 1834. In the United States, the first major wire-cable suspension bridge was the Wire Bridge at Fairmount in Philadelphia, Pennsylvania. Designed by Charles Ellet Jr. and completed in 1842, it had a span of 109 m. Ellet's Niagara Falls suspension bridge (1847–48) was abandoned before completion. It was used as scaffolding for John A. Roebling 's double decker railroad and carriage bridge (1855). The Otto Beit Bridge (1938–1939)
2772-576: The north cable in 2002. At this point the bridge was discovered to be beyond permanent repair and would have to be abandoned and replaced by a new structure to be built adjacent to the aging bridge. Work then shifted to temporary strengthening. For the south cable, MDOT in August 2003 hired Pittsfield, Maine-based Cianbro Corp. under a $ 4-million emergency contract. The rehabilitation used a single wire thickness (2-inch-diameter (5.1 cm) galvanized helical 91-wire strands) to facilitate fabricating and installing
2835-506: The observatory due to the elevator doors not opening. The bridge has been the site of at least twelve suicides since its opening; more are suspected. This included the Rev. Robert Carlson, a well-known figure in the Bangor area, who was found in the Penobscot River beneath the bridge on November 13, 2011. Other suicidal people have been talked down from the bridge before they jumped. Before
2898-406: The pillars to deck-level supports, and further continue to connections with anchors in the ground. The roadway is supported by vertical suspender cables or rods, called hangers. In some circumstances, the towers may sit on a bluff or canyon edge where the road may proceed directly to the main span. Otherwise, the bridge will typically have two smaller spans, running between either pair of pillars and
2961-570: The previous monthly. They could not determine if the phones were functional when a March 5, 2017 suicide, the first since the phones were installed, occurred. The phones were found to be out of order on June 23, 2017, when an abandoned car on the bridge resulted in a search of the Penobscot River by authorities looking for its driver. The emergency phones on the Penobscot Narrows Bridge were reported out of order following another suicide in 2021. They were subsequently replaced. In May 2022,
3024-421: The pylons. Each epoxy-coated steel strand is carried inside the cradle in a one-inch steel tube. Each strand acts independently, allowing for removal, inspection and replacement of individual strands. The cable-stay system was designed with a system that uses pressurized nitrogen gas to defend against corrosion. In June 2007, six reference strands within three stays were replaced with carbon fiber strands —
3087-413: The railing and the walking layer of Gyalpo's bridges used wires. The stress points that carried the screed were reinforced by the iron chains. Before the use of iron chains it is thought that Gyalpo used ropes from twisted willows or yak skins. He may have also used tightly bound cloth. The Inca used rope bridges , documented as early as 1615. It is not known when they were first made. Queshuachaca
3150-592: The roadbed, particularly owing to the unfavorable effects of using plate girders, discovered from the Tacoma Narrows Bridge (1940) bridge collapse. In the 1960s, developments in bridge aerodynamics allowed the re-introduction of plate structures as shallow box girders , first seen on the Severn bridge , built 1961–1966. In the picture of the Yichang Bridge , note the very sharp entry edge and sloping undergirders in
3213-500: The sag." The new auxiliary cables are connected to existing double suspender cables by 1 + 1 ⁄ 8 -inch-diameter (2.9 cm) steel rods, then tensioned with 30-ton (27.2 metric ton) jacks, bringing the new cables about 3 feet (1 m) from the main cables. A new construction, the Penobscot Narrows Bridge , was built alongside the older one. The new bridge was opened to traffic on December 30, 2006, at which point
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#17330846856963276-401: The suspension bridge shown. This enables this type of construction to be used without the danger of vortex shedding and consequent aeroelastic effects, such as those that destroyed the original Tacoma Narrows bridge. Three kinds of forces operate on any bridge: the dead load, the live load, and the dynamic load. Dead load refers to the weight of the bridge itself. Like any other structure,
3339-508: The ten bridges with the longest spans, followed by the length of the span and the year the bridge opened for traffic: (Chronological) Broughton Suspension Bridge (England) was an iron chain bridge built in 1826. One of Europe's first suspension bridges, it collapsed in 1831 due to mechanical resonance induced by troops marching in step. As a result of the incident, the British Army issued an order that troops should "break step" when crossing
3402-489: The towers. In cable-stayed bridges, the towers are the primary load-bearing structures that transmit the bridge loads to the ground. A cantilever approach is often used to support the bridge deck near the towers, but lengths further from them are supported by cables running directly to the towers. By design, all static horizontal forces of the cable-stayed bridge are balanced so that the supporting towers do not tend to tilt or slide and so must only resist horizontal forces from
3465-554: The use of iron chains in his version of simple suspension bridges . In 1433, Gyalpo built eight bridges in eastern Bhutan . The last surviving chain-linked bridge of Gyalpo's was the Thangtong Gyalpo Bridge in Duksum en route to Trashi Yangtse , which was finally washed away in 2004. Gyalpo's iron chain bridges did not include a suspended-deck bridge , which is the standard on all modern suspension bridges today. Instead, both
3528-423: The weight of the cables is small compared to the weight of the deck. One can see the shape from the constant increase of the gradient of the cable with linear (deck) distance, this increase in gradient at each connection with the deck providing a net upward support force. Combined with the relatively simple constraints placed upon the actual deck, that makes the suspension bridge much simpler to design and analyze than
3591-442: Was 135 feet (41.1 m) above water level to allow passage of large ships. The total cost of the span was less than $ 850,000 in 1931 dollars (about $ 12 million in 2010 dollars), significantly under its allocated budget. David B. Steinman , of Robinson and Steinman , was the designer. The bridge was fabricated by American Bridge Company (superstructure) and Merritt-Chapman & Scott (substructure). Technologically,
3654-529: Was accepted. Demolition was delayed until 2012, beginning with the November 20 removal of the bridge's flag poles, and was completed in June 2013. The following sources are referenced in the HAER documentation: Suspension bridge A suspension bridge is a type of bridge in which the deck is hung below suspension cables on vertical suspenders. The first modern examples of this type of bridge were built in
3717-581: Was also the first bridge to make use of the Vierendeel truss in its two towers, giving it an effect that Steinman called "artistic, emphasizing horizontal and vertical lines." This attractive and effective truss design was later used in a number of important bridges, including the Triborough Bridge and Golden Gate Bridge . The Waldo–Hancock Bridge was noted at the time for its economy of design and construction. It cost far less than had been appropriated by
3780-643: Was built between 1829 and 1832, replacing a wooden bridge further downstream which collapsed in 1828. It is the only suspension bridge across the non-tidal Thames. The Széchenyi Chain Bridge , (designed in 1840, opened in 1849), spanning the River Danube in Budapest, was also designed by William Clark and it is a larger-scale version of Marlow Bridge. An interesting variation is Thornewill and Warham 's Ferry Bridge in Burton-on-Trent , Staffordshire (1889), where
3843-515: Was completed by 2013. The bridge was 2,040 feet (621.8 m) long with a clear center span of 800 feet (243.8 m) between towers. It had two 350-foot (106.7 m) side spans and carried a 20-foot (6.1 m) wide roadway with two 3 + 1 ⁄ 2 -foot (1.1 m) sidewalks . It used stiffening trusses that are 9 feet (2.7 m) deep. Each of the main catenary cables were 9 + 5 ⁄ 8 inches (24.4 cm) in diameter, and consisted of 37 strands of 37 wires. The deck
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#17330846856963906-404: Was the first modern suspension bridge outside the United States built with parallel wire cables. Two towers/pillars, two suspension cables, four suspension cable anchors, multiple suspender cables, the bridge deck. The main cables of a suspension bridge will form a catenary when hanging under their own weight only. When supporting the deck, the cables will instead form a parabola , assuming
3969-417: Was walked across, connected to a 7 ⁄ 8 -inch-diameter (2.2 cm) pull cable, then winched back across and connected to the strand, which was fed through a tensioner holding back about 15,000 pounds (7,000 kg) to smooth the pull. "We hooked and rehooked one strand per day on average," says Archie J. Wheaton, Cianbro project superintendent. "The strands were connected to anchor rods; then we set
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