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61-646: The Newburgh–Beacon Bridge is a continuous truss toll bridge that spans the Hudson River in New York State . The bridge carries Interstate 84 (I-84) and New York State Route 52 (NY 52) between Newburgh and Beacon and consists of two separate spans. The original northern span, which now carries westbound traffic, was opened on November 2, 1963, as a two-lane (one in each direction) bridge. A second span, completed in 1980, now carries all eastbound traffic. The span provides connections to

122-444: A cruck frame or a couple of rafters. One engineering definition is: "A truss is a single plane framework of individual structural member [sic] connected at their ends of forms a series of triangle [sic] to span a large distance". A truss consists of typically (but not necessarily) straight members connected at joints, traditionally termed panel points . Trusses are typically (but not necessarily ) composed of triangles because of

183-412: A lattice . The Vierendeel truss is a structure where the members are not triangulated but form rectangular openings, and is a frame with fixed joints that are capable of transferring and resisting bending moments . As such, it does not fit the strict definition of a truss (since it contains non-two-force members): regular trusses comprise members that are commonly assumed to have pinned joints, with

244-468: A $ 13,900,750 project was completed that rebuilt the overpass carrying traffic over US 9W in Newburgh, in order to provide better clearance for truck traffic below on Route 9W and to meet current interstate highway standards. At midnight on July 7, 2021, the bridge was converted to all-electronic tolling on the eastbound span, involved in this was the removal of a large segment of roadway. In late 2020,

305-420: A $ 95 million dollar project to replace the westbound spans deck was commmenced. It was considered mostly complete by October 1, 2022, nine months ahead of schedule. On November 27, 2022, the walkway had its curfew removed, allowing pedestrians to walk across it 24/7. Eastbound passenger vehicles are currently (as of May 1, 2023) charged a cash toll of $ 2.15 to cross the span, or $ 1.65 for E-ZPass. The toll plaza

366-647: A 13-term member of the House. In 2006, the west approach was repaved and a new truck inspection area was built to allow the State Police to conduct inspections in a safe area that would not interfere with regular traffic flow. The toll plaza was reconfigured in August 2010. In October 2013, a $ 94.7 million dollar project to replace the eastbound spans deck was commenced. It was completed in October 2015. In 2019,

427-617: A 130-mile (210 km) stretch, from the Outerbridge Crossing in the south to the Rip Van Winkle Bridge in the north, were also changed to south- or eastbound-only at that time. In 2003, the Port Authority raised the speed limit for the three inner E-ZPass lanes at the toll plaza from 15 to 25 miles per hour (25 to 40 km/h), separating these lanes from the rest of the eight-lane toll plaza by

488-527: A barrier. Two years later, the tollbooths adjacent to the 25 mph E-ZPass lanes were removed and overhead gantries were installed with electronic tag readers to permit E-ZPass vehicles to travel at 45 miles per hour (70 km/h) in special high-speed lanes. Motorists using the high-speed E-ZPass lanes cannot use exit 1 to Page Avenue, which is located immediately after the toll plaza. Open road tolling began on April 24, 2019. The tollbooths were dismantled, and drivers are no longer able to pay cash at

549-399: A breakdown lane at night and off-peak travel times. When the right lane is being used as a shoulder, a red X appears on the signs above it, while a green arrow illuminates when the lane is used for travel during peak times. In 1997, the bridges were rededicated in honor of Hamilton Fish III , a 12-term member of the U.S. House of Representatives , and his son and namesake Hamilton Fish IV ,

610-476: A ceiling joist , and in other mechanical structures such as bicycles and aircraft. Because of the stability of this shape and the methods of analysis used to calculate the forces within it, a truss composed entirely of triangles is known as a simple truss. However, a simple truss is often defined more restrictively by demanding that it can be constructed through successive addition of pairs of members, each connected to two existing joints and to each other to form

671-403: A larger cross section than on a previous iteration requires giving other members a larger cross section as well, to hold the greater weight of the first member—one needs to go through another iteration to find exactly how much greater the other members need to be. Sometimes the designer goes through several iterations of the design process to converge on the "right" cross section for each member. On

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732-402: A matrix method such as the direct stiffness method , the flexibility method , or the finite element method. Illustrated is a simple, statically determinate flat truss with 9 joints and (2 x 9) − 3 = 15 members. External loads are concentrated in the outer joints. Since this is a symmetrical truss with symmetrical vertical loads, the reactive forces at A and B are vertical, equal, and half

793-404: A new joint, and this definition does not require a simple truss to comprise only triangles. The traditional diamond-shape bicycle frame, which utilizes two conjoined triangles, is an example of a simple truss. A planar truss lies in a single plane . Planar trusses are typically used in parallel to form roofs and bridges. The depth of a truss, or the height between the upper and lower chords,

854-523: A second parallel span south of the original. On November 1, 1980, this second, parallel span, also designed by Modjeski & Masters but constructed by the American Bridge Company , was opened to traffic. This eastbound span was built with three 12-foot (3.7 m) travel lanes, and a 10-foot (3.0 m) right shoulder. Because of this, unlike the westbound span, there is no need to reduce the travel lanes to two during off-peak times. It

915-566: A truss are called 'top chords' and are typically in compression , the bottom beams are called 'bottom chords', and are typically in tension . The interior beams are called webs , and the areas inside the webs are called panels , or from graphic statics (see Cremona diagram ) 'polygons'. Truss derives from the Old French word trousse , from around 1200 AD, which means "collection of things bound together". The term truss has often been used to describe any assembly of members such as

976-538: Is a 393 meter (1,291 foot) long truss bridge built in 1912. The structure is composed of nine Pratt truss spans of varying lengths. The bridge is still in use today. The Wright Flyer used a Pratt truss in its wing construction, as the minimization of compression member lengths allowed for lower aerodynamic drag . Named for their shape, bowstring trusses were first used for arched truss bridges , often confused with tied-arch bridges . Thousands of bowstring trusses were used during World War II for holding up

1037-422: Is a roof or floor truss whose wood members are connected with metal connector plates . Truss members form a series of equilateral triangles, alternating up and down. Truss members are made up of all equivalent equilateral triangles. The minimum composition is two regular tetrahedrons along with an octahedron. They fill up three dimensional space in a variety of configurations. [REDACTED] The Pratt truss

1098-515: Is also made of weathering steel (believed to be COR-TEN or similar, although sources are not clear), the surface of which intentionally corrodes, forming a brown colored protective layer that does not require paint. The bicycle path on the eastbound span was opened in 1981, making it the second interstate funded bike path in the United States. The original span was closed for a major renovation from December 1980 to June 1984, in order widen

1159-588: Is located on the eastern (Beacon) shore. Originally, tolls were collected in both directions. The tolls of eleven other New York–New Jersey and Hudson River crossings along a 130-mile (210 km) stretch, from the Outerbridge Crossing in the south to the Rip Van Winkle Bridge in the north, were also changed to eastbound-only at that time. In 2019, the bridge authority announced that tolls on its five Hudson River crossings would increase each year beginning in 2020 and ending in 2023. As of May 1, 2021,

1220-496: Is preferable to a braced-frame system, which would leave some areas obstructed by the diagonal braces. A truss that is assumed to comprise members that are connected by means of pin joints, and which is supported at both ends by means of hinged joints and rollers, is described as being statically determinate . Newton's Laws apply to the structure as a whole, as well as to each node or joint. In order for any node that may be subject to an external load or force to remain static in space,

1281-464: Is similar to a king post truss in that the outer supports are angled towards the centre of the structure. The primary difference is the horizontal extension at the centre which relies on beam action to provide mechanical stability. This truss style is only suitable for relatively short spans. Lenticular trusses, patented in 1878 by William Douglas (although the Gaunless Bridge of 1823 was

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1342-422: Is the force in the member, γ is a safety factor (typically 1.5 but depending on building codes ) and σ y is the yield tensile strength of the steel used. The members under compression also have to be designed to be safe against buckling. The weight of a truss member depends directly on its cross section—that weight partially determines how strong the other members of the truss need to be. Giving one member

1403-405: Is the simplest space truss, consisting of six members that meet at four joints. Large planar structures may be composed from tetrahedrons with common edges, and they are also employed in the base structures of large free-standing power line pylons. There are two basic types of truss: A combination of the two is a truncated truss, used in hip roof construction. A metal plate-connected wood truss

1464-465: Is what makes it an efficient structural form. A solid girder or beam of equal strength would have substantial weight and material cost as compared to a truss. For a given span , a deeper truss will require less material in the chords and greater material in the verticals and diagonals. An optimum depth of the truss will maximize the efficiency. A space frame truss is a three-dimensional framework of members pinned at their ends. A tetrahedron shape

1525-528: The New York State Thruway ( I-87 ) and U.S. Route 9W (US 9W) in Newburgh and US 9 in Fishkill . The bridges includes a 2,204-foot-long (672 m) cantilever span, with a main span of 1,000 feet (300 m) and side spans of 602 feet (183 m). The total length of all spans and approaches is 7,855 feet (2,394 m) for the north span and 7,789 feet (2,374 m) for

1586-520: The Outerbridge , is a cantilever bridge that spans the Arthur Kill between Perth Amboy , New Jersey , and Staten Island , New York . It carries New York State Route 440 and New Jersey Route 440 , with the two roads connecting at the state border at the river’s center. The Outerbridge Crossing is one of three vehicular bridges connecting New Jersey with Staten Island, and like

1647-493: The "Staten Island Bridges Plan" ($ 7.69 per trip for cars at all times). Users with E-ZPass issued from agencies outside of New Jersey and New York are charged the tolls-by-mail rate. Tolls are only collected for eastbound traffic. Originally, tolls were collected in both directions. In August 1970, the toll was abolished for westbound drivers, and at the same time, eastbound drivers saw their tolls doubled. The tolls of eleven other New York–New Jersey and Hudson River crossings along

1708-728: The auspices of the Port of New York Authority, now the Port Authority of New York and New Jersey , which currently operates it. It opened simultaneously with the first Goethals Bridge on June 29, 1928. Both spans had similar designs prior to replacement of the Goethals with the current cable-stayed bridge in 2018. Neither bridge saw high traffic counts until the opening of the Verrazzano-Narrows Bridge in 1964. Traffic counts on both bridges were also depressed due to

1769-407: The connections may also be required to transfer bending moment. Wood posts enable the fabrication of strong, direct, yet inexpensive connections between large trusses and walls. Exact details for post-to-truss connections vary from designer to designer, and may be influenced by post type. Solid-sawn timber and glulam posts are generally notched to form a truss bearing surface. The truss is rested on

1830-533: The current toll for passenger cars traveling eastbound on the Mid-Hudson Bridge was $ 1.75 in cash, $ 1.45 for E-ZPass users. In May 2022, tolls will rise to $ 1.55 for E-ZPass users and $ 2 for cash payers. In 2023, the E-ZPass toll will increase to $ 1.65, and the cash toll will rise to $ 2.15. Continuous truss In engineering, a truss is a structure that "consists of two-force members only, where

1891-531: The curved roofs of aircraft hangars and other military buildings. Many variations exist in the arrangements of the members connecting the nodes of the upper arc with those of the lower, straight sequence of members, from nearly isosceles triangles to a variant of the Pratt truss. One of the simplest truss styles to implement, the king post consists of two angled supports leaning into a common vertical support. The queen post truss, sometimes queenpost or queenspost ,

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1952-430: The deck to accommodate three 12-foot (3.7 m) travel lanes, increase its strengthening, install Variable lane signs, and repaint it a shade of brown to match the color of the eastbound span. After work was completed, the original span was converted to serve westbound traffic, and the 1980 span was converted to serve eastbound traffic, though it still had no permanent shoulders. to allow the right lane to be designated as

2013-452: The design decisions beyond mere matters of economics. Modern materials such as prestressed concrete and fabrication methods, such as automated welding , have significantly influenced the design of modern bridges . Once the force on each member is known, the next step is to determine the cross section of the individual truss members. For members under tension the cross-sectional area A can be found using A = F × γ / σ y , where F

2074-646: The effects of the Great Depression and World War II . The Outerbridge Crossing has undergone numerous repairs as a result of the high volume of traffic that crosses the bridge each day. On October 11, 2013, the Port Authority announced the completion of the bridge's repaving project. On March 2, 2017, Port Authority Executive Director Patrick Foye announced the funding of a study into a potential replacement bridge. The Outerbridge Crossing carried 32,438,000 vehicles (both directions) in 2006, or approximately 90,000 each day. As of January 7, 2024 ,

2135-403: The equilibrium condition described. Because the forces in each of its two main girders are essentially planar, a truss is usually modeled as a two-dimensional plane frame. However if there are significant out-of-plane forces, the structure must be modeled as a three-dimensional space. The analysis of trusses often assumes that loads are applied to joints only and not at intermediate points along

2196-414: The exact arrangement of forces is depending on the type of truss and again on the direction of bending. In the truss shown above right, the vertical members are in tension, and the diagonals are in compression. In addition to carrying the static forces, the members serve additional functions of stabilizing each other, preventing buckling . In the adjacent picture, the top chord is prevented from buckling by

2257-461: The first of the type), have the top and bottom chords of the truss arched, forming a lens shape. A lenticular pony truss bridge is a bridge design that involves a lenticular truss extending above and below the roadbed. American architect Ithiel Town designed Town's Lattice Truss as an alternative to heavy-timber bridges. His design, patented in 1820 and 1835, uses easy-to-handle planks arranged diagonally with short spaces in between them, to form

2318-417: The following conditions must hold: the sums of all (horizontal and vertical) forces, as well as all moments acting about the node equal zero. Analysis of these conditions at each node yields the magnitude of the compression or tension forces. Trusses that are supported at more than two positions are said to be statically indeterminate , and the application of Newton's Laws alone is not sufficient to determine

2379-509: The implication that no moments exist at the jointed ends. This style of structure was named after the Belgian engineer Arthur Vierendeel , who developed the design in 1896. Its use for bridges is rare due to higher costs compared to a triangulated truss. The utility of this type of structure in buildings is that a large amount of the exterior envelope remains unobstructed and can be used for windows and door openings. In some applications this

2440-501: The member forces. In order for a truss with pin-connected members to be stable, it does not need to be entirely composed of triangles. In mathematical terms, the following necessary condition for stability of a simple truss exists: where m is the total number of truss members, j is the total number of joints and r is the number of reactions (equal to 3 generally) in a 2-dimensional structure. When m = 2 j − 3 {\displaystyle m=2j-3} ,

2501-546: The members are organized so that the assemblage as a whole behaves as a single object". A "two-force member" is a structural component where force is applied to only two points. Although this rigorous definition allows the members to have any shape connected in any stable configuration, trusses typically comprise five or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes . In this typical context, external forces and reactions to those forces are considered to act only at

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2562-562: The members means that longer diagonal members are only in tension for gravity load effects. This allows these members to be used more efficiently, as slenderness effects related to buckling under compression loads (which are compounded by the length of the member) will typically not control the design. Therefore, for given planar truss with a fixed depth, the Pratt configuration is usually the most efficient under static, vertical loading. The Southern Pacific Railroad bridge in Tempe , Arizona

2623-446: The members. Component connections are critical to the structural integrity of a framing system. In buildings with large, clearspan wood trusses, the most critical connections are those between the truss and its supports. In addition to gravity-induced forces (a.k.a. bearing loads), these connections must resist shear forces acting perpendicular to the plane of the truss and uplift forces due to wind. Depending upon overall building design,

2684-431: The members. The weight of the members is often insignificant compared to the applied loads and so is often omitted; alternatively, half of the weight of each member may be applied to its two end joints. Provided that the members are long and slender, the moments transmitted through the joints are negligible, and the junctions can be treated as " hinges " or "pin-joints". Under these simplifying assumptions, every member of

2745-427: The minimum cross section of the members, the last step in the design of a truss would be detailing of the bolted joints , e.g., involving shear stress of the bolt connections used in the joints. Based on the needs of the project, truss internal connections (joints) can be designed as rigid, semi rigid, or hinged. Rigid connections can allow transfer of bending moments leading to development of secondary bending moments in

2806-477: The nodes and result in forces in the members that are either tensile or compressive . For straight members, moments ( torques ) are explicitly excluded because, and only because, all the joints in a truss are treated as revolutes , as is necessary for the links to be two-force members. A planar truss is one where all members and nodes lie within a two-dimensional plane, while a space frame has members and nodes that extend into three dimensions . The top beams in

2867-400: The notches and bolted into place. A special plate/bracket may be added to increase connection load transfer capabilities. With mechanically-laminated posts, the truss may rest on a shortened outer-ply or on a shortened inner-ply. The later scenario places the bolts in double shear and is a very effective connection. Outerbridge Crossing The Outerbridge Crossing , also known as

2928-438: The other hand, reducing the size of one member from the previous iteration merely makes the other members have a larger (and more expensive) safety factor than is technically necessary, but doesn't require another iteration to find a buildable truss. The effect of the weight of the individual truss members in a large truss, such as a bridge, is usually insignificant compared to the force of the external loads. After determining

2989-531: The others, is maintained and operated by the Port Authority of New York and New Jersey . The others are the Bayonne Bridge (also carrying Route 440), which connects Staten Island with Bayonne , and the Goethals Bridge (carrying I-278 , which connects the island with Elizabeth ). Constructed from 1925 to 1928, the bridge was named for Eugenius Harvey Outerbridge , the first chairman of

3050-425: The presence of bracing and by the stiffness of the web members. The inclusion of the elements shown is largely an engineering decision based upon economics, being a balance between the costs of raw materials, off-site fabrication, component transportation, on-site erection, the availability of machinery and the cost of labor. In other cases the appearance of the structure may take on greater importance and so influence

3111-406: The relation (a) is necessary, it is not sufficient for stability, which also depends on the truss geometry, support conditions and the load carrying capacity of the members. Some structures are built with more than this minimum number of truss members. Those structures may survive even when some of the members fail. Their member forces depend on the relative stiffness of the members, in addition to

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3172-400: The same function as the flanges of an I-beam . Which chord carries tension and which carries compression depends on the overall direction of bending . In the truss pictured above right, the bottom chord is in tension, and the top chord in compression. The diagonal and vertical members form the truss web , and carry the shear stress . Individually, they are also in tension and compression,

3233-752: The south span. The bridges, owned by the New York State Bridge Authority , carry six lanes of traffic and approximately 65,000 vehicles per day. The bridge is officially known as the Hamilton Fish Newburgh–Beacon Bridge . Although original plans called for a four-lane bridge, funding difficulties resulted in the reduction in lanes. This span was designed by Modjeski & Masters and constructed by Frederick Snare Corporation , Drave, and Bethlehem Steel . The now westbound bridge opened on November 2, 1963, carrying one lane of traffic in each direction. In August 1970,

3294-404: The structural stability of that shape and design. A triangle is the simplest geometric figure that will not change shape when the lengths of the sides are fixed. In comparison, both the angles and the lengths of a four-sided figure must be fixed for it to retain its shape. The simplest form of a truss is one single triangle. This type of truss is seen in a framed roof consisting of rafters and

3355-582: The then– Port of New York Authority and a resident of Staten Island. Rather than calling it the "Outerbridge Bridge", the span was labeled a "crossing". The bridge's etymology is sometimes incorrectly attributed to the fact that the Outerbridge Crossing is the most remote bridge in New York City and the southernmost crossing in New York state. The bridge is of a steel cantilever construction, designed by John Alexander Low Waddell and built under

3416-425: The toll was abolished for westbound drivers, and at the same time, eastbound drivers saw their tolls doubled. The bridge originally carried NY 52 traffic, which was light, but the construction of Interstate 84 pushed the bridge over capacity, and planning for additional capacity began in 1972. After considering double-decking (which the original bridge was not designed for) the decision was taken by NYSBA to add

3477-458: The tolls-by-mail rate going from New Jersey to New York City are $ 17.63 for cars and motorcycles; there is no toll for passenger vehicles going from New York City to New Jersey. New Jersey and New York–issued E-ZPass users are charged $ 13.38 for cars and $ 12.38 for motorcycles during off-peak hours, and $ 15.38 for cars and $ 14.38 for motorcycles during peak hours. Frequent users traveling more than three trips per month can receive discounts under

3538-421: The total load. The internal forces in the members of the truss can be calculated in a variety of ways, including graphical methods: A truss can be thought of as a beam where the web consists of a series of separate members instead of a continuous plate. In the truss, the lower horizontal member (the bottom chord ) and the upper horizontal member (the top chord ) carry tension and compression , fulfilling

3599-415: The truss is said to be statically determinate , because the ( m +3) internal member forces and support reactions can then be completely determined by 2 j equilibrium equations, once we know the external loads and the geometry of the truss. Given a certain number of joints, this is the minimum number of members, in the sense that if any member is taken out (or fails), then the truss as a whole fails. While

3660-519: The truss is then subjected to pure compression or pure tension forces – shear, bending moment, and other more-complex stresses are all practically zero. Trusses are physically stronger than other ways of arranging structural elements, because nearly every material can resist a much larger load in tension or compression than in shear, bending, torsion, or other kinds of force. These simplifications make trusses easier to analyze. Structural analysis of trusses of any type can readily be carried out using

3721-415: Was patented in 1844 by two Boston railway engineers, Caleb Pratt and his son Thomas Willis Pratt . The design uses vertical members for compression and diagonal members to respond to tension . The Pratt truss design remained popular as bridge designers switched from wood to iron, and from iron to steel. This continued popularity of the Pratt truss is probably due to the fact that the configuration of

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