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109-672: The Tweed Bridge is a stone-built road bridge of five spans over the River Tweed in Peebles , in the Scottish Borders . The Tweed Bridge is medieval in origin, although the exact date of its construction is unknown. Records show that a stone bridge has been maintained at the site since the middle of the 15th century, and work done in 1465 may have been the construction of a new bridge or substantial rebuilding or maintenance of an existing one. A mason known as John of Peebles may have worked on

218-596: A bridge-restaurant which is a bridge built to serve as a restaurant. Other suspension bridge towers carry transmission antennas. Conservationists use wildlife overpasses to reduce habitat fragmentation and animal-vehicle collisions. The first animal bridges sprung up in France in the 1950s, and these types of bridges are now used worldwide to protect both large and small wildlife. Bridges are subject to unplanned uses as well. The areas underneath some bridges have become makeshift shelters and homes to homeless people, and

327-563: A Circum Arabian Nomadic Pastoral Complex developed in the period from the climatic crisis of 6200 BC, partly as a result of an increasing emphasis in PPNB cultures upon domesticated animals, and a fusion with Harifian hunter gatherers in the Southern Levant, with affiliate connections with the cultures of Fayyum and the Eastern Desert of Egypt . Cultures practicing this lifestyle spread down

436-520: A bridge is to be designed, standards authorities specify simplified notional load models, notably HL-93, intended to give the same load effects as the characteristic maximum values. The Eurocode is an example of a standard for bridge traffic loading that was developed in this way. Most bridge standards are only applicable for short and medium spans - for example, the Eurocode is only applicable for loaded lengths up to 200 m. Longer spans are dealt with on

545-471: A case-by-case basis. It is generally accepted that the intensity of load reduces as span increases because the probability of many trucks being closely spaced and extremely heavy reduces as the number of trucks involved increases. It is also generally assumed that short spans are governed by a small number of trucks traveling at high speed, with an allowance for dynamics. Longer spans on the other hand, are governed by congested traffic and no allowance for dynamics

654-480: A combination of structural health monitoring and testing. This is regulated in country-specific engineer standards and includes an ongoing monitoring every three to six months, a simple test or inspection every two to three years and a major inspection every six to ten years. In Europe, the cost of maintenance is considerable and is higher in some countries than spending on new bridges. The lifetime of welded steel bridges can be significantly extended by aftertreatment of

763-524: A culture contemporaneous with the Cishan and Xinglongwa cultures of about 6000–5000 BC, Neolithic cultures east of the Taihang Mountains , filling in an archaeological gap between the two Northern Chinese cultures. The total excavated area is more than 1,200 square yards (1,000 m ; 0.10 ha), and the collection of Neolithic findings at the site encompasses two phases. Between 3000 and 1900 BC,

872-399: A different site, and re-used. They are important in military engineering and are also used to carry traffic while an old bridge is being rebuilt. Movable bridges are designed to move out of the way of boats or other kinds of traffic, which would otherwise be too tall to fit. These are generally electrically powered. The Tank bridge transporter (TBT) has the same cross-country performance as

981-511: A division into five periods. They also advanced the idea of a transitional stage between the PPNA and PPNB between 8800 and 8600 BC at sites like Jerf el Ahmar and Tell Aswad . Alluvial plains ( Sumer / Elam ). Low rainfall makes irrigation systems necessary. Ubaid culture originated from 6200 BC. The earliest evidence of Neolithic culture in northeast Africa was found in the archaeological sites of Bir Kiseiba and Nabta Playa in what

1090-412: A dramatic increase in social inequality in most of the areas where it occurred; New Guinea being a notable exception. Possession of livestock allowed competition between households and resulted in inherited inequalities of wealth. Neolithic pastoralists who controlled large herds gradually acquired more livestock, and this made economic inequalities more pronounced. However, evidence of social inequality

1199-594: A few will predominate. The separation of forces and moments may be quite clear. In a suspension or cable-stayed bridge , the elements in tension are distinct in shape and placement. In other cases the forces may be distributed among a large number of members, as in a truss. The world's longest beam bridge is Lake Pontchartrain Causeway in southern Louisiana in the United States, at 23.83 miles (38.35 km), with individual spans of 56 feet (17 m). Beam bridges are

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1308-546: A living tradition in small and extremely remote and inaccessible pockets of West Papua . Polished stone adze and axes are used in the present day (as of 2008 ) in areas where the availability of metal implements is limited. This is likely to cease altogether in the next few years as the older generation die off and steel blades and chainsaws prevail. In 2012, news was released about a new farming site discovered in Munam-ri , Goseong , Gangwon Province , South Korea , which may be

1417-586: A non-hierarchical system of organization existed is debatable, and there is no evidence that explicitly suggests that Neolithic societies functioned under any dominating class or individual, as was the case in the chiefdoms of the European Early Bronze Age . Possible exceptions to this include Iraq during the Ubaid period and England beginning in the Early Neolithic (4100–3000 BC). Theories to explain

1526-627: A rarely used and not very useful concept in discussing Australian prehistory . During most of the Neolithic age of Eurasia , people lived in small tribes composed of multiple bands or lineages. There is little scientific evidence of developed social stratification in most Neolithic societies; social stratification is more associated with the later Bronze Age . Although some late Eurasian Neolithic societies formed complex stratified chiefdoms or even states , generally states evolved in Eurasia only with

1635-553: A simple type of suspension bridge , were used by the Inca civilization in the Andes mountains of South America, just prior to European colonization in the 16th century. The Ashanti built bridges over streams and rivers . They were constructed by pounding four large forked tree trunks into the stream bed, placing beams along these forked pillars, then positioning cross-beams that were finally covered with four to six inches of dirt. During

1744-578: A span of 552 m (1,811 ft). The bridge was opened 29 April 2009, in Chongqing , China. The longest suspension bridge in the world is the 4,608 m (15,118 ft) 1915 Çanakkale Bridge in Turkey. The longest cable-stayed bridge since 2012 is the 1,104 m (3,622 ft) Russky Bridge in Vladivostok , Russia. Some Engineers sub-divide 'beam' bridges into slab, beam-and-slab and box girder on

1853-732: A stream. Often in palaces, a bridge will be built over an artificial waterway as symbolic of a passage to an important place or state of mind. A set of five bridges cross a sinuous waterway in an important courtyard of the Forbidden City in Beijing, China. The central bridge was reserved exclusively for the use of the Emperor and Empress, with their attendants. The estimated life of bridges varies between 25 and 80 years depending on location and material. Bridges may age hundred years with proper maintenance and rehabilitation. Bridge maintenance consisting of

1962-479: A tank even when fully loaded. It can deploy, drop off and load bridges independently, but it cannot recover them. Double-decked (or double-decker) bridges have two levels, such as the George Washington Bridge , connecting New York City to Bergen County , New Jersey , US, as the world's busiest bridge, carrying 102 million vehicles annually; truss work between the roadway levels provided stiffness to

2071-752: A term coined in the 1920s by the Australian archaeologist Vere Gordon Childe . One potential benefit of the development and increasing sophistication of farming technology was the possibility of producing surplus crop yields, in other words, food supplies in excess of the immediate needs of the community. Surpluses could be stored for later use, or possibly traded for other necessities or luxuries. Agricultural life afforded securities that nomadic life could not, and sedentary farming populations grew faster than nomadic. However, early farmers were also adversely affected in times of famine , such as may be caused by drought or pests . In instances where agriculture had become

2180-456: Is a bridge that carries water, resembling a viaduct, which is a bridge that connects points of equal height. A road-rail bridge carries both road and rail traffic. Overway is a term for a bridge that separates incompatible intersecting traffic, especially road and rail. Some bridges accommodate other purposes, such as the tower of Nový Most Bridge in Bratislava , which features a restaurant, or

2289-538: Is a large body of evidence for fortified settlements at Linearbandkeramik sites along the Rhine , as at least some villages were fortified for some time with a palisade and an outer ditch. Settlements with palisades and weapon-traumatized bones, such as those found at the Talheim Death Pit , have been discovered and demonstrate that "...systematic violence between groups" and warfare was probably much more common during

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2398-574: Is an early example of a double-decked bridge. The upper level carries a railway, and the lower level is used for road traffic. Other examples include Britannia Bridge over the Menai Strait and Craigavon Bridge in Derry, Northern Ireland. The Oresund Bridge between Copenhagen and Malmö consists of a four-lane highway on the upper level and a pair of railway tracks at the lower level. Tower Bridge in London

2507-549: Is better explained by lineal fission and polygyny. The shelter of early people changed dramatically from the Upper Paleolithic to the Neolithic era. In the Paleolithic, people did not normally live in permanent constructions. In the Neolithic, mud brick houses started appearing that were coated with plaster. The growth of agriculture made permanent houses far more common. At Çatalhöyük 9,000 years ago, doorways were made on

2616-485: Is different example of a double-decked bridge, with the central section consisting of a low-level bascule span and a high-level footbridge . A viaduct is made up of multiple bridges connected into one longer structure. The longest and some of the highest bridges are viaducts, such as the Lake Pontchartrain Causeway and Millau Viaduct . A multi-way bridge has three or more separate spans which meet near

2725-417: Is led by architects, bridges are usually designed by engineers. This follows from the importance of the engineering requirements; namely spanning the obstacle and having the durability to survive, with minimal maintenance, in an aggressive outdoor environment. Bridges are first analysed; the bending moment and shear force distributions are calculated due to the applied loads. For this, the finite element method

2834-540: Is needed. Calculating the loading due to congested traffic remains a challenge as there is a paucity of data on inter-vehicle gaps, both within-lane and inter-lane, in congested conditions. Weigh-in-Motion (WIM) systems provide data on inter-vehicle gaps but only operate well in free flowing traffic conditions. Some authors have used cameras to measure gaps and vehicle lengths in jammed situations and have inferred weights from lengths using WIM data. Others have used microsimulation to generate typical clusters of vehicles on

2943-531: Is now southwest Egypt. Domestication of sheep and goats reached Egypt from the Near East possibly as early as 6000 BC. Graeme Barker states "The first indisputable evidence for domestic plants and animals in the Nile valley is not until the early fifth millennium BC in northern Egypt and a thousand years later further south, in both cases as part of strategies that still relied heavily on fishing, hunting, and

3052-568: Is otherwise difficult or impossible to cross. There are many different designs of bridges, each serving a particular purpose and applicable to different situations. Designs of bridges vary depending on factors such as the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it. The earliest bridges were likely made with fallen trees and stepping stones . The Neolithic people built boardwalk bridges across marshland. The Arkadiko Bridge , dating from

3161-1017: Is still disputed, as settlements such as Çatalhöyük reveal a lack of difference in the size of homes and burial sites, suggesting a more egalitarian society with no evidence of the concept of capital, although some homes do appear slightly larger or more elaborately decorated than others. Families and households were still largely independent economically, and the household was probably the center of life. However, excavations in Central Europe have revealed that early Neolithic Linear Ceramic cultures (" Linearbandkeramik ") were building large arrangements of circular ditches between 4800 and 4600 BC. These structures (and their later counterparts such as causewayed enclosures , burial mounds , and henge ) required considerable time and labour to construct, which suggests that some influential individuals were able to organise and direct human labour – though non-hierarchical and voluntary work remain possibilities. There

3270-737: Is the most popular. The analysis can be one-, two-, or three-dimensional. For the majority of bridges, a two-dimensional plate model (often with stiffening beams) is sufficient or an upstand finite element model. On completion of the analysis, the bridge is designed to resist the applied bending moments and shear forces, section sizes are selected with sufficient capacity to resist the stresses. Many bridges are made of prestressed concrete which has good durability properties, either by pre-tensioning of beams prior to installation or post-tensioning on site. In most countries, bridges, like other structures, are designed according to Load and Resistance Factor Design (LRFD) principles. In simple terms, this means that

3379-601: The Bronze Age began about 3500 BC, replacing the Neolithic cultures. Around 10,000 BC the first fully developed Neolithic cultures belonging to the phase Pre-Pottery Neolithic A (PPNA) appeared in the Fertile Crescent. Around 10,700–9400 BC a settlement was established in Tell Qaramel , 10 miles (16 km) north of Aleppo . The settlement included two temples dating to 9650 BC. Around 9000 BC during

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3488-618: The Hellenistic era can be found in the Peloponnese. The greatest bridge builders of antiquity were the ancient Romans . The Romans built arch bridges and aqueducts that could stand in conditions that would damage or destroy earlier designs, some of which still stand today. An example is the Alcántara Bridge , built over the river Tagus , in Spain. The Romans also used cement, which reduced

3597-610: The Jordan Valley ; Israel (notably Ain Mallaha , Nahal Oren , and Kfar HaHoresh ); and in Byblos , Lebanon . The start of Neolithic 1 overlaps the Tahunian and Heavy Neolithic periods to some degree. The major advance of Neolithic 1 was true farming. In the proto-Neolithic Natufian cultures, wild cereals were harvested, and perhaps early seed selection and re-seeding occurred. The grain

3706-543: The Longshan culture existed in the middle and lower Yellow River valley areas of northern China. Towards the end of the 3rd millennium BC, the population decreased sharply in most of the region and many of the larger centres were abandoned, possibly due to environmental change linked to the end of the Holocene Climatic Optimum . The 'Neolithic' (defined in this paragraph as using polished stone implements) remains

3815-581: The Natufian culture , when pioneering use of wild cereals evolved into early farming . The Natufian period or "proto-Neolithic" lasted from 12,500 to 9,500 BC, and is taken to overlap with the Pre-Pottery Neolithic A (PPNA) of 10,200–8800 BC. As the Natufians had become dependent on wild cereals in their diet, and a sedentary way of life had begun among them, the climatic changes associated with

3924-637: The Red Sea shoreline and moved east from Syria into southern Iraq . The Late Neolithic began around 6,400 BC in the Fertile Crescent . By then distinctive cultures emerged, with pottery like the Halafian (Turkey, Syria, Northern Mesopotamia) and Ubaid (Southern Mesopotamia). This period has been further divided into PNA (Pottery Neolithic A) and PNB (Pottery Neolithic B) at some sites. The Chalcolithic (Stone-Bronze) period began about 4500 BC, then

4033-525: The Rift Valley of East Africa and surrounding areas during a time period known as the Pastoral Neolithic . They were South Cushitic speaking pastoralists, who tended to bury their dead in cairns whilst their toolkit was characterized by stone bowls, pestles, grindstones and earthenware pots. Through archaeology, historical linguistics and archaeogenetics, they conventionally have been identified with

4142-833: The University of Minnesota ). Likewise, in Toronto , the Prince Edward Viaduct has five lanes of motor traffic, bicycle lanes, and sidewalks on its upper deck; and a pair of tracks for the Bloor–Danforth subway line on its lower deck. The western span of the San Francisco–Oakland Bay Bridge also has two levels. Robert Stephenson 's High Level Bridge across the River Tyne in Newcastle upon Tyne , completed in 1849,

4251-477: The Younger Dryas (about 10,000 BC) are thought to have forced people to develop farming. The founder crops of the Fertile Crescent were wheat , lentil , pea , chickpeas , bitter vetch, and flax. Among the other major crop domesticated were rice, millet, maize (corn), and potatoes. Crops were usually domesticated in a single location and ancestral wild species are still found. [1] Early Neolithic farming

4360-495: The river Severn . With the Industrial Revolution in the 19th century, truss systems of wrought iron were developed for larger bridges, but iron does not have the tensile strength to support large loads. With the advent of steel, which has a high tensile strength, much larger bridges were built, many using the ideas of Gustave Eiffel . In Canada and the United States, numerous timber covered bridges were built in

4469-545: The 10th millennium BC. Early development occurred in the Levant (e.g. Pre-Pottery Neolithic A and Pre-Pottery Neolithic B ) and from there spread eastwards and westwards. Neolithic cultures are also attested in southeastern Anatolia and northern Mesopotamia by around 8000 BC. Anatolian Neolithic farmers derived a significant portion of their ancestry from the Anatolian hunter-gatherers (AHG), suggesting that agriculture

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4578-521: The 13th century BC, in the Peloponnese is one of the oldest arch bridges in existence and use. The Oxford English Dictionary traces the origin of the word bridge to an Old English word brycg , of the same meaning.   The Oxford English Dictionary also notes that there is some suggestion that the word can be traced directly back to Proto-Indo-European *bʰrēw-. However, they also note that "this poses semantic problems." The origin of

4687-511: The 18th century, there were many innovations in the design of timber bridges by Hans Ulrich Grubenmann , Johannes Grubenmann , as well as others. The first book on bridge engineering was written by Hubert Gautier in 1716. A major breakthrough in bridge technology came with the erection of the Iron Bridge in Shropshire, England in 1779. It used cast iron for the first time as arches to cross

4796-709: The Balkans from 6000 BC, and in Central Europe by around 5800 BC ( La Hoguette ). Among the earliest cultural complexes of this area are the Sesklo culture in Thessaly, which later expanded in the Balkans giving rise to Starčevo-Körös (Cris), Linearbandkeramik , and Vinča . Through a combination of cultural diffusion and migration of peoples , the Neolithic traditions spread west and northwards to reach northwestern Europe by around 4500 BC. The Vinča culture may have created

4905-516: The Bronze Age, eventually giving rise to permanently settled farming towns , and later cities and states whose larger populations could be sustained by the increased productivity from cultivated lands. The profound differences in human interactions and subsistence methods associated with the onset of early agricultural practices in the Neolithic have been called the Neolithic Revolution ,

5014-491: The Maltese archipelago) and of Mnajdra (Malta) are notable for their gigantic Neolithic structures, the oldest of which date back to around 3600 BC. The Hypogeum of Ħal-Saflieni , Paola , Malta, is a subterranean structure excavated around 2500 BC; originally a sanctuary, it became a necropolis , the only prehistoric underground temple in the world, and shows a degree of artistry in stone sculpture unique in prehistory to

5123-443: The Maltese islands. After 2500 BC, these islands were depopulated for several decades until the arrival of a new influx of Bronze Age immigrants, a culture that cremated its dead and introduced smaller megalithic structures called dolmens to Malta. In most cases there are small chambers here, with the cover made of a large slab placed on upright stones. They are claimed to belong to a population different from that which built

5232-624: The Middle East. The neolithization of Northwestern Africa was initiated by Iberian , Levantine (and perhaps Sicilian ) migrants around 5500-5300 BC. During the Early Neolithic period, farming was introduced by Europeans and was subsequently adopted by the locals. During the Middle Neolithic period, an influx of ancestry from the Levant appeared in Northwestern Africa, coinciding with

5341-622: The Neolithic followed the Mesolithic (Middle Stone Age) and then lasted until later. In Ancient Egypt , the Neolithic lasted until the Protodynastic period , c. 3150 BC. In China , it lasted until circa 2000 BC with the rise of the pre-Shang Erlitou culture , as it did in Scandinavia . Following the ASPRO chronology , the Neolithic started in around 10,200 BC in the Levant , arising from

5450-465: The Neolithic than in the preceding Paleolithic period. This supplanted an earlier view of the Linear Pottery Culture as living a "peaceful, unfortified lifestyle". Control of labour and inter-group conflict is characteristic of tribal groups with social rank that are headed by a charismatic individual – either a ' big man ' or a proto- chief – functioning as a lineage-group head. Whether

5559-769: The PPNA, one of the world's first towns, Jericho , appeared in the Levant. It was surrounded by a stone wall, may have contained a population of up to 2,000–3,000 people, and contained a massive stone tower. Around 6400 BC the Halaf culture appeared in Syria and Northern Mesopotamia. In 1981, a team of researchers from the Maison de l'Orient et de la Méditerranée , including Jacques Cauvin and Oliver Aurenche, divided Near East Neolithic chronology into ten periods (0 to 9) based on social, economic and cultural characteristics. In 2002, Danielle Stordeur and Frédéric Abbès advanced this system with

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5668-544: The Town Council. On the south side of the bridge the remains of Second World War defences were evident until the road was resurfaced. The bridge was listed as a category A listed building in 1971. Plans are being considered for an additional bridge over the Tweed in the town. The five spans vary in length from 38 feet (12 m) to 42 feet (13 m). The oldest part of the bridge uses arches which are almost circular, but

5777-566: The Tweed Bridge is the Cuddy Bridge , a single arch bridge over the Eddleston Water , a tributary of the Tweed. Road bridge A bridge is a structure built to span a physical obstacle (such as a body of water , valley , road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually something that

5886-414: The apparent implied egalitarianism of Neolithic (and Paleolithic) societies have arisen, notably the Marxist concept of primitive communism . Genetic evidence indicates that a drop in Y-chromosomal diversity occurred during the Neolithic. Initially believed to be a result of high incidence of violence and high rates of male mortality, more recent analysis suggests that the reduced Y-chromosomal diversity

5995-496: The appearance of the bridge can have great importance. Often, this is the case with a large bridge that serves as an entrance to a city, or crosses over a main harbor entrance. These are sometimes known as signature bridges. Designers of bridges in parks and along parkways often place more importance on aesthetics, as well. Examples include the stone-faced bridges along the Taconic State Parkway in New York. Bridges are typically more aesthetically pleasing if they are simple in shape,

6104-558: The area". The research team will perform accelerator mass spectrometry (AMS) dating to retrieve a more precise date for the site. In Mesoamerica , a similar set of events (i.e., crop domestication and sedentary lifestyles) occurred by around 4500 BC in South America, but possibly as early as 11,000–10,000 BC. These cultures are usually not referred to as belonging to the Neolithic; in North America, different terms are used such as Formative stage instead of mid-late Neolithic, Archaic Era instead of Early Neolithic, and Paleo-Indian for

6213-499: The area's first Afroasiatic -speaking settlers. Archaeological dating of livestock bones and burial cairns has also established the cultural complex as the earliest center of pastoralism and stone construction in the region. In southeast Europe agrarian societies first appeared in the 7th millennium BC , attested by one of the earliest farming sites of Europe, discovered in Vashtëmi , southeastern Albania and dating back to 6500 BC. In most of Western Europe in followed over

6322-436: The arrival of pastoralism in the region. The earliest evidence for pottery, domestic cereals and animal husbandry is found in Morocco, specifically at Kaf el-Ghar . The Pastoral Neolithic was a period in Africa's prehistory marking the beginning of food production on the continent following the Later Stone Age . In contrast to the Neolithic in other parts of the world, which saw the development of farming societies,

6431-416: The attention of the general public in the 1990s by the novel, movie and play The Bridges of Madison County . In 1927, welding pioneer Stefan Bryła designed the first welded road bridge in the world, the Maurzyce Bridge which was later built across the river Słudwia at Maurzyce near Łowicz , Poland in 1929. In 1995, the American Welding Society presented the Historic Welded Structure Award for

6540-596: The basis of their cross-section. A slab can be solid or voided (though this is no longer favored for inspectability reasons) while beam-and-slab consists of concrete or steel girders connected by a concrete slab. A box-girder cross-section consists of a single-cell or multi-cellular box. In recent years, integral bridge construction has also become popular. Most bridges are fixed bridges, meaning they have no moving parts and stay in one place until they fail or are demolished. Temporary bridges, such as Bailey bridges , are designed to be assembled, taken apart, transported to

6649-423: The bow and arrow and ceramic pottery were also introduced. In later periods cities of considerable size developed, and some metallurgy by 700 BC. Australia, in contrast to New Guinea , has generally been held not to have had a Neolithic period, with a hunter-gatherer lifestyle continuing until the arrival of Europeans. This view can be challenged in terms of the definition of agriculture, but "Neolithic" remains

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6758-417: The bridge at that time. A plaque on the bridge states that it was originally a wooden bridge clad in stone. It was reconstructed in 1663 using stone from St Andrew's Church which had been destroyed in 1548 by an English army as part of the Rough Wooing . John Hisplop added three additional arches to the south end of the bridge in 1799, but these were removed when the Peebles Railway was built. The bridge

6867-437: The bridge to Poland. Bridges can be categorized in several different ways. Common categories include the type of structural elements used, by what they carry, whether they are fixed or movable, and by the materials used. Bridges may be classified by how the actions of tension , compression , bending , torsion and shear are distributed through their structure. Most bridges will employ all of these to some degree, but only

6976-435: The bridge. Neolithic The Neolithic began about 12,000 years ago, when farming appeared in the Epipalaeolithic Near East and Mesopotamia , and later in other parts of the world. It lasted in the Near East until the transitional period of the Chalcolithic (Copper Age) from about 6,500 years ago (4500 BC), marked by the development of metallurgy , leading up to the Bronze Age and Iron Age . In other places,

7085-439: The center of the bridge. Multi-way bridges with only three spans appear as a "T" or "Y" when viewed from above. Multi-way bridges are extremely rare. The Tridge , Margaret Bridge , and Zanesville Y-Bridge are examples. A bridge can be categorized by what it is designed to carry, such as trains, pedestrian or road traffic ( road bridge ), a pipeline ( Pipe bridge ) or waterway for water transport or barge traffic. An aqueduct

7194-399: The dead, which were plastered with mud to make facial features. The rest of the corpse could have been left outside the settlement to decay until only the bones were left, then the bones were buried inside the settlement underneath the floor or between houses. Work at the site of 'Ain Ghazal in Jordan has indicated a later Pre-Pottery Neolithic C period. Juris Zarins has proposed that

7303-467: The deck is thinner in proportion to its span, the lines of the structure are continuous, and the shapes of the structural elements reflect the forces acting on them. To create a beautiful image, some bridges are built much taller than necessary. This type, often found in east-Asian style gardens, is called a Moon bridge , evoking a rising full moon. Other garden bridges may cross only a dry bed of stream-washed pebbles, intended only to convey an impression of

7412-542: The earliest farmland known to date in east Asia. "No remains of an agricultural field from the Neolithic period have been found in any East Asian country before, the institute said, adding that the discovery reveals that the history of agricultural cultivation at least began during the period on the Korean Peninsula ". The farm was dated between 3600 and 3000 BC. Pottery, stone projectile points, and possible houses were also found. "In 2002, researchers discovered prehistoric earthenware , jade earrings, among other items in

7521-408: The earliest system of writing, the Vinča signs , though archaeologist Shan Winn believes they most likely represented pictograms and ideograms rather than a truly developed form of writing. The Cucuteni-Trypillian culture built enormous settlements in Romania, Moldova and Ukraine from 5300 to 2300 BC. The megalithic temple complexes of Ġgantija on the Mediterranean island of Gozo (in

7630-446: The enclosures also suggest grain and meat storage. The Neolithic 2 (PPNB) began around 8800 BC according to the ASPRO chronology in the Levant ( Jericho , West Bank). As with the PPNA dates, there are two versions from the same laboratories noted above. This system of terminology, however, is not convenient for southeast Anatolia and settlements of the middle Anatolia basin. A settlement of 3,000 inhabitants called 'Ain Ghazal

7739-422: The first human-made bridges with significant span were probably intentionally felled trees. Among the oldest timber bridges is the Holzbrücke Rapperswil-Hurden bridge that crossed upper Lake Zürich in Switzerland; prehistoric timber pilings discovered to the west of the Seedamm causeway date back to 1523 BC. The first wooden footbridge there led across Lake Zürich; it was reconstructed several times through

7848-570: The first cultivated crop and mark the invention of the technology of farming. This occurred centuries before the first cultivation of grains. Settlements became more permanent, with circular houses, much like those of the Natufians, with single rooms. However, these houses were for the first time made of mudbrick . The settlement had a surrounding stone wall and perhaps a stone tower (as in Jericho). The wall served as protection from nearby groups, as protection from floods, or to keep animals penned. Some of

7957-545: The first form of African food production was mobile pastoralism , or ways of life centered on the herding and management of livestock. The term "Pastoral Neolithic" is used most often by archaeologists to describe early pastoralist periods in the Sahara , as well as in eastern Africa . The Savanna Pastoral Neolithic or SPN (formerly known as the Stone Bowl Culture ) is a collection of ancient societies that appeared in

8066-503: The gathering of wild plants" and suggests that these subsistence changes were not due to farmers migrating from the Near East but was an indigenous development, with cereals either indigenous or obtained through exchange. Other scholars argue that the primary stimulus for agriculture and domesticated animals (as well as mud-brick architecture and other Neolithic cultural features) in Egypt was from

8175-748: The late 1700s to the late 1800s, reminiscent of earlier designs in Germany and Switzerland. Some covered bridges were also built in Asia. In later years, some were partly made of stone or metal but the trusses were usually still made of wood; in the United States, there were three styles of trusses, the Queen Post, the Burr Arch and the Town Lattice. Hundreds of these structures still stand in North America. They were brought to

8284-464: The late 2nd century AD, when the Roman Empire built a 6-metre-wide (20 ft) wooden bridge to carry transport across the lake. Between 1358 and 1360, Rudolf IV, Duke of Austria , built a 'new' wooden bridge across the lake that was used until 1878; it was approximately 1,450 metres (4,760 ft) long and 4 metres (13 ft) wide. On 6 April 2001, a reconstruction of the original wooden footbridge

8393-427: The load is factored up by a factor greater than unity, while the resistance or capacity of the structure is factored down, by a factor less than unity. The effect of the factored load (stress, bending moment) should be less than the factored resistance to that effect. Both of these factors allow for uncertainty and are greater when the uncertainty is greater. Most bridges are utilitarian in appearance, but in some cases,

8502-506: The more modern parts use flatter segmental arches. On the upstream side the piers have triangular ashlar cutwaters , and rounded profiles on the downstream side. At the north end of the bridge is an arched ramp to the east that leads to Tweed Green. The Tweed Bridge is the only road crossing of the Tweed within Peebles. It carries the B7062 public road, which is two lanes wide at this point. Near to

8611-540: The next 1,500 years. Populations began to rise after 3500 BC, with further dips and rises occurring between 3000 and 2500 BC but varying in date between regions. Around this time is the Neolithic decline , when populations collapsed across most of Europe, possibly caused by climatic conditions, plague, or mass migration. Settled life, encompassing the transition from foraging to farming and pastoralism, began in South Asia in

8720-440: The next two thousand years, but in some parts of Northwest Europe it is much later, lasting just under 3,000 years from c. 4500 BC–1700 BC. Recent advances in archaeogenetics have confirmed that the spread of agriculture from the Middle East to Europe was strongly correlated with the migration of early farmers from Anatolia about 9,000 years ago, and was not just a cultural exchange. Anthropomorphic figurines have been found in

8829-629: The past, these load models were agreed by standard drafting committees of experts but today, this situation is changing. It is now possible to measure the components of bridge traffic load, to weigh trucks, using weigh-in-motion (WIM) technologies. With extensive WIM databases, it is possible to calculate the maximum expected load effect in the specified return period. This is an active area of research, addressing issues of opposing direction lanes, side-by-side (same direction) lanes, traffic growth, permit/non-permit vehicles and long-span bridges (see below). Rather than repeat this complex process every time

8938-523: The preceding period. The Formative stage is equivalent to the Neolithic Revolution period in Europe, Asia, and Africa. In the southwestern United States it occurred from 500 to 1200 AD when there was a dramatic increase in population and development of large villages supported by agriculture based on dryland farming of corn (maize), and later, beans, squash, and domesticated turkeys. During this period

9047-454: The predominant way of life, the sensitivity to these shortages could be particularly acute, affecting agrarian populations to an extent that otherwise may not have been routinely experienced by prior hunter-gatherer communities. Nevertheless, agrarian communities generally proved successful, and their growth and the expansion of territory under cultivation continued. Another significant change undergone by many of these newly agrarian communities

9156-417: The previous megalithic temples. It is presumed the population arrived from Sicily because of the similarity of Maltese dolmens to some small constructions found there. With some exceptions, population levels rose rapidly at the beginning of the Neolithic until they reached the carrying capacity . This was followed by a population crash of "enormous magnitude" after 5000 BC, with levels remaining low during

9265-496: The previous reliance on an essentially nomadic hunter-gatherer subsistence technique or pastoral transhumance was at first supplemented, and then increasingly replaced by, a reliance upon the foods produced from cultivated lands. These developments are also believed to have greatly encouraged the growth of settlements, since it may be supposed that the increased need to spend more time and labor in tending crop fields required more localized dwellings. This trend would continue into

9374-419: The principles of Load and Resistance Factor Design . Before factoring to allow for uncertainty, the load effect is generally considered to be the maximum characteristic value in a specified return period . Notably, in Europe, it is the maximum value expected in 1000 years. Bridge standards generally include a load model, deemed to represent the characteristic maximum load to be expected in the return period. In

9483-422: The region of Balochistan , Pakistan, around 7,000 BC. At the site of Mehrgarh , Balochistan, presence can be documented of the domestication of wheat and barley, rapidly followed by that of goats, sheep, and cattle. In April 2006, it was announced in the scientific journal Nature that the oldest (and first Early Neolithic ) evidence for the drilling of teeth in vivo (using bow drills and flint tips)

9592-674: The rise of metallurgy, and most Neolithic societies on the whole were relatively simple and egalitarian. Beyond Eurasia, however, states were formed during the local Neolithic in three areas, namely in the Preceramic Andes with the Caral-Supe Civilization , Formative Mesoamerica and Ancient Hawaiʻi . However, most Neolithic societies were noticeably more hierarchical than the Upper Paleolithic cultures that preceded them and hunter-gatherer cultures in general. The domestication of large animals (c. 8000 BC) resulted in

9701-742: The roadways and reduced movement of the upper level when the lower level was installed three decades after the upper level. The Tsing Ma Bridge and Kap Shui Mun Bridge in Hong Kong have six lanes on their upper decks, and on their lower decks there are two lanes and a pair of tracks for MTR metro trains. Some double-decked bridges only use one level for street traffic; the Washington Avenue Bridge in Minneapolis reserves its lower level for automobile and light rail traffic and its upper level for pedestrian and bicycle traffic (predominantly students at

9810-743: The roof, with ladders positioned both on the inside and outside of the houses. Stilt-house settlements were common in the Alpine and Pianura Padana ( Terramare ) region. Remains have been found in the Ljubljana Marsh in Slovenia and at the Mondsee and Attersee lakes in Upper Austria , for example. A significant and far-reaching shift in human subsistence and lifestyle was to be brought about in areas where crop farming and cultivation were first developed:

9919-698: The same year, has the span of 90 m (295 ft) and crosses the valley of the Syrabach River. The difference between the two is that the Solkan Bridge was built from stone blocks, whereas the Friedensbrücke was built from a mixture of crushed stone and cement mortar. The world's largest arch bridge is the Chaotianmen Bridge over the Yangtze River with a length of 1,741 m (5,712 ft) and

10028-637: The simplest and oldest type of bridge in use today, and are a popular type. Some cantilever bridges also have a smaller beam connecting the two cantilevers, for extra strength. The largest cantilever bridge is the 549-metre (1,801 ft) Quebec Bridge in Quebec, Canada. With the span of 220 metres (720 ft), the Solkan Bridge over the Soča River at Solkan in Slovenia is the second-largest stone bridge in

10137-790: The time of the Warring States period , the oldest surviving stone bridge in China is the Zhaozhou Bridge , built from 595 to 605 AD during the Sui dynasty . This bridge is also historically significant as it is the world's oldest open-spandrel stone segmental arch bridge. European segmental arch bridges date back to at least the Alconétar Bridge (approximately 2nd century AD), while the enormous Roman era Trajan's Bridge (105 AD) featured open-spandrel segmental arches in wooden construction. Rope bridges ,

10246-740: The undertimbers of bridges all around the world are spots of prevalent graffiti. Some bridges attract people attempting suicide, and become known as suicide bridges . The materials used to build the structure are also used to categorize bridges. Until the end of the 18th century, bridges were made out of timber, stone and masonry. Modern bridges are currently built in concrete, steel, fiber reinforced polymers (FRP), stainless steel or combinations of those materials. Living bridges have been constructed of live plants such as Ficus elastica tree roots in India and wisteria vines in Japan. Unlike buildings whose design

10355-507: The variation of strength found in natural stone. One type of cement, called pozzolana , consisted of water, lime , sand, and volcanic rock . Brick and mortar bridges were built after the Roman era , as the technology for cement was lost (then later rediscovered). In India, the Arthashastra treatise by Kautilya mentions the construction of dams and bridges. A Mauryan bridge near Girnar

10464-571: The vicinity, and may be the oldest known human-made place of worship. At least seven stone circles, covering 25 acres (10 ha), contain limestone pillars carved with animals, insects, and birds. Stone tools were used by perhaps as many as hundreds of people to create the pillars, which might have supported roofs. Other early PPNA sites dating to around 9500–9000 BC have been found in Palestine , notably in Tell es-Sultan (ancient Jericho ) and Gilgal in

10573-433: The weld transitions . This results in a potential high benefit, using existing bridges far beyond the planned lifetime. While the response of a bridge to the applied loading is well understood, the applied traffic loading itself is still the subject of research. This is a statistical problem as loading is highly variable, particularly for road bridges. Load Effects in bridges (stresses, bending moments) are designed for using

10682-632: The word for the card game of the same name is unknown.   The simplest and earliest types of bridges were stepping stones . Neolithic people also built a form of boardwalk across marshes ; examples of such bridges include the Sweet Track and the Post Track in England, approximately 6000 years old. Ancient people would also have used log bridges consisting of logs that fell naturally or were intentionally felled or placed across streams. Some of

10791-448: The world and the longest railroad stone bridge. It was completed in 1905. Its arch, which was constructed from over 5,000 tonnes (4,900 long tons; 5,500 short tons) of stone blocks in just 18 days, is the second-largest stone arch in the world, surpassed only by the Friedensbrücke (Syratalviadukt) in Plauen , and the largest railroad stone arch. The arch of the Friedensbrücke, which was built in

10900-520: The world, such as Africa , South Asia and Southeast Asia , independent domestication events led to their own regionally distinctive Neolithic cultures, which arose completely independently of those in Europe and Southwest Asia . Early Japanese societies and other East Asian cultures used pottery before developing agriculture. In the Middle East , cultures identified as Neolithic began appearing in

11009-419: Was adopted in site by these hunter-gatherers and not spread by demic diffusion into the region. The Neolithic 1 (PPNA) period began around 10,000 BC in the Levant . A temple area in southeastern Turkey at Göbekli Tepe , dated to around 9500 BC, may be regarded as the beginning of the period. This site was developed by nomadic hunter-gatherer tribes, as evidenced by the lack of permanent housing in

11118-840: Was found in Mehrgarh. In South India, the Neolithic began by 6500 BC and lasted until around 1400 BC when the Megalithic transition period began. South Indian Neolithic is characterized by Ash mounds from 2500 BC in Karnataka region, expanded later to Tamil Nadu . In East Asia, the earliest sites include the Nanzhuangtou culture around 9500–9000 BC, Pengtoushan culture around 7500–6100 BC, and Peiligang culture around 7000–5000 BC. The prehistoric Beifudi site near Yixian in Hebei Province, China, contains relics of

11227-409: Was found in the outskirts of Amman , Jordan . Considered to be one of the largest prehistoric settlements in the Near East , it was continuously inhabited from approximately 7250 BC to approximately 5000 BC. Settlements have rectangular mud-brick houses where the family lived together in single or multiple rooms. Burial findings suggest an ancestor cult where people preserved skulls of

11336-450: Was ground into flour. Emmer wheat was domesticated, and animals were herded and domesticated ( animal husbandry and selective breeding ). In 2006, remains of figs were discovered in a house in Jericho dated to 9400 BC. The figs are of a mutant variety that cannot be pollinated by insects, and therefore the trees can only reproduce from cuttings. This evidence suggests that figs were

11445-431: Was limited to a narrow range of plants, both wild and domesticated, which included einkorn wheat , millet and spelt , and the keeping of dogs . By about 8000 BC, it included domesticated sheep and goats , cattle and pigs . Not all of these cultural elements characteristic of the Neolithic appeared everywhere in the same order: the earliest farming societies in the Near East did not use pottery. In other parts of

11554-402: Was one of diet . Pre-agrarian diets varied by region, season, available local plant and animal resources and degree of pastoralism and hunting. Post-agrarian diet was restricted to a limited package of successfully cultivated cereal grains, plants and to a variable extent domesticated animals and animal products. Supplementation of diet by hunting and gathering was to variable degrees precluded by

11663-573: Was opened; it is also the longest wooden bridge in Switzerland. The Arkadiko Bridge is one of four Mycenaean corbel arch bridges part of a former network of roads, designed to accommodate chariots , between the fort of Tiryns and town of Epidauros in the Peloponnese , in southern Greece . Dating to the Greek Bronze Age (13th century BC), it is one of the oldest arch bridges still in existence and use. Several intact, arched stone bridges from

11772-510: Was surveyed by James Princep . The bridge was swept away during a flood, and later repaired by Puspagupta, the chief architect of emperor Chandragupta I . The use of stronger bridges using plaited bamboo and iron chain was visible in India by about the 4th century. A number of bridges, both for military and commercial purposes, were constructed by the Mughal administration in India. Although large bridges of wooden construction existed in China at

11881-422: Was widened from 8 feet (2.4 m) to 21 feet (6.4 m) in 1834 by adding stonework to both sides. This work was done by John and Thomas Smith of Darnick , and the cost of around £1,000 was funded by public subscription. Between 1897 and 1900, it was widened again to 40 feet (12 m) by adding to the downstream side. This work, which cost about £8,000 , was done by McTaggart, Cowan and Barker, and funded by

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