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A road is a thoroughfare for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets , whose primary function is to serve as public spaces, the main function of roads is transportation.

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132-498: Macadam is a type of road construction pioneered by Scottish engineer John Loudon McAdam around 1820, in which crushed stone is placed in shallow, convex layers and compacted thoroughly. A binding layer of stone dust (crushed stone from the original material) may form; it may also, after rolling, be covered with a cement or bituminous binder to keep dust and stones together. The method simplified what had been considered state-of-the-art at that point. Pierre-Marie-Jérôme Trésaguet

264-470: A Roman road ); another was at the present-day Inns Court . Isolated Roman villas and small forts and settlements were also scattered throughout the area. Bristol was founded by 1000; by about 1020, it was a trading centre with a mint producing silver pennies bearing its name. By 1067, Brycgstow was a well-fortified burh , and that year the townsmen beat back a raiding party from Ireland led by three of Harold Godwinson 's sons. Under Norman rule,

396-400: A road use tax , is payable on some vehicles used on the public road. The definition of a road depends on the definition of a highway; there is no formal definition for a highway in the relevant Act. A 1984 ruling said "the land over which a public right of way exists is known as a highway; and although most highways have been made up into roads, and most easements of way exist over footpaths,

528-411: A single carriageway road is converted into dual carriageway by building a second separate carriageway alongside the first, it is usually referred to as duplication , twinning or doubling . The original carriageway is changed from two-way to become one-way, while the new carriageway is one-way in the opposite direction. In the same way as converting railway lines from single track to double track ,

660-411: A statue of Colston was pulled down from its plinth by protestors and pushed into Bristol Harbour. The statue was recovered on 11 June and has become a museum exhibit. Bristol City council consists of 70 councillors representing 34 wards, with between one and three per ward serving four-year terms. As of May 2024, no party has an overall controlling majority, but Green Party are the largest group on

792-457: A 25 to 50 millimeter hole through the pavement into the sub-base with a dry-bit roto-hammer . Next, a two-part epoxy is poured into the hole – dyed for visual clarity. Once the epoxy hardens, technicians drill through the hole. If a void is present, the epoxy will stick to the core and provide physical evidence. Common stabilization materials include pozzolan -cement grout and polyurethane. The requirements for slab stabilization are strength and

924-614: A May 2009 report by the American Association of State Highway and Transportation Officials (AASHTO) and TRIP – a national transportation research organization – driving on rough roads costs the average American motorist approximately $ 400 a year in extra vehicle operating costs. Drivers living in urban areas with populations more than 250,000 are paying upwards of $ 750 more annually because of accelerated vehicle deterioration, increased maintenance, additional fuel consumption , and tire wear caused by poor road conditions. When

1056-591: A car, van, motorbike or taxi, 2.2% commute by rail and 9.8% by bus, while 19.6% walk. The Runnymede Trust found in 2017 that Bristol "ranked 7th out of the 348 districts of England & Wales (1=worst) on the Index of Multiple Inequality." In terms of employment, the report found that "ethnic minorities are disadvantaged compared to white British people nationally, but this is to a greater extent in Bristol, particularly for black groups." Black people in Bristol experience

1188-417: A compulsory load line on ships. By 1867, ships were getting larger and the meanders in the river Avon prevented boats over 300 ft (90 m) from reaching the harbour, resulting in falling trade. The port facilities were migrating downstream to Avonmouth and new industrial complexes were founded there. Some of the traditional industries including copper and brass manufacture went into decline, but

1320-687: A developed area between the Bristol city boundary and the M4, M5 and M32 motorways (now in South Gloucestershire) was so named as part of a 1987 plan prepared by the Northavon District Council of Avon county. The West of England Combined Authority was created on 9 February 2017. Covering Bristol and the rest of the old Avon county with the exception of North Somerset, the new combined authority has responsibility for regional planning, roads, and local transport, and to

1452-419: A double-wheeled, steel roller to insert the rod to the desired depth. After inserting the backer rod, the sealant is placed into the joint. There are various materials to choose for this method including hot pour bituminous liquid, silicone and preformed compression seals. Careful design and construction of roads can increase road traffic safety and reduce the harm (deaths, injuries, and property damage) on

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1584-605: A layer of brushwood and heather. John Loudon McAdam was born in Ayr , Scotland, in 1756. In 1787, he became a trustee of the Ayrshire Turnpike in the Scottish Lowlands and during the next seven years his hobby became an obsession. He moved to Bristol , England, in 1802 and became a Commissioner for Paving in 1806. On 15 January 1816, he was elected surveyor general of roads for the Bristol turnpike trust and

1716-509: A lesser extent, education and business investment. The authority is led by the Mayor of the West of England , Dan Norris . Bristol's boundaries can be defined in several ways, including those of the city itself, the developed area, or Greater Bristol . The city council boundary is the narrowest definition of the city itself. However, it unusually includes a large, roughly rectangular section of

1848-413: A major two-level (and at one point, three-level) roadway in the downtown area, are being rebuilt with a designed service life of 100 years. Virtually all roads require some form of maintenance before they come to the end of their service life. Pro-active agencies use pavement management techniques to continually monitor road conditions and schedule preventive maintenance treatments as needed to prolong

1980-428: A road as "a line of communication (travelled way) using a stabilized base other than rails or air strips open to public traffic, primarily for the use of road motor vehicles running on their own wheels", which includes "bridges, tunnels, supporting structures, junctions, crossings, interchanges, and toll roads, but not cycle paths". The Eurostat , ITF and UNECE Glossary for Transport Statistics Illustrated defines

2112-494: A road as a "Line of communication (traveled way) open to public traffic, primarily for the use of road motor vehicles, using a stabilized base other than rails or air strips. [...] Included are paved roads and other roads with a stabilized base, e.g. gravel roads. Roads also cover streets, bridges, tunnels, supporting structures, junctions, crossings and interchanges. Toll roads are also included. Excluded are dedicated cycle lanes." The 1968 Vienna Convention on Road Traffic defines

2244-510: A road as the entire surface of any way or street open to public traffic. In urban areas roads may diverge through a city or village and be named as streets, serving a dual function as urban space easement and route. Modern roads are normally smoothed, paved, or otherwise prepared to allow easy travel . Part 2, Division 1, clauses 11–13 of the National Transport Commission Regulations 2006 defines

2376-524: A road in Australia as 'an area that is open to or used by the public and is developed for, or has as one of its main uses, the driving or riding of motor vehicles.' Further, it defines a shoulder (typical an area of the road outside the edge line, or the curb) and a road-related area which includes green areas separating roads, areas designated for cyclists and areas generally accessible to the public for driving, riding or parking vehicles. In New Zealand,

2508-426: A roadway consisting of three layers of stones laid on a crowned subgrade with side ditches for drainage. The first two layers consisted of angular hand-broken aggregate , maximum size 3 inches (7.6 cm), to a depth of about 8 inches (20 cm). The third layer was about 2 inches (5 cm) thick with a maximum aggregate size of 1 inch (2.5 cm). This top level surface permitted a smoother shape and protected

2640-487: A shipbuilding and manufacturing centre. By the 14th century, Bristol, York and Norwich were England's largest medieval towns after London. One-third to one-half of the population died in the Black Death of 1348–49, which checked population growth, and its population remained between 10,000 and 12,000 for most of the 15th and 16th centuries. During the 15th century, Bristol was the second most important port in

2772-475: Is 106 mi (171 km) west of London, 77 mi (124 km) south-southwest of Birmingham and 26 mi (42 km) east of the Welsh capital Cardiff . Areas adjoining the city fall within a loosely defined area known as Greater Bristol . Bath is located 11 mi (18 km) south east of the city centre, Weston-super-Mare is 18 mi (29 km) to the south west and the Welsh city of Newport

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2904-503: Is 19 mi (31 km) to the north west. The climate is oceanic ( Köppen : Cfb) , milder than most places in England and United Kingdom. Located in southern England, Bristol is one of the warmest cities in the UK with a mean annual temperature of approximately 10.5 °C (50.9 °F). It is among the sunniest, with 1,541–1,885   hours of sunshine per year. Although the city

3036-432: Is 40 years for new bitumen and concrete pavement. Maintenance is considered in the whole life cost of the road with service at 10, 20 and 30-year milestones. Roads can be and are designed for a variety of lives (8-, 15-, 30-, and 60-year designs). When pavement lasts longer than its intended life, it may have been overbuilt, and the original costs may have been too high. When a pavement fails before its intended design life,

3168-433: Is a non-destructive method of solving this problem and is usually employed with other concrete pavement restoration methods including patching and diamond grinding. The technique restores support to concrete slabs by filing small voids that develop underneath the concrete slab at joints, cracks or the pavement edge. The process consists of pumping a cementitious grout or polyurethane mixture through holes drilled through

3300-487: Is also common. Some road fixtures such as road signs and fire hydrants are designed to collapse on impact. Light poles are designed to break at the base rather than violently stop a car that hits them. Highway authorities may also remove larger trees from the immediate vicinity of the road. During heavy rains, if the elevation of the road surface is not higher than the surrounding landscape, it may result in flooding. Speed limits can improve road traffic safety and reduce

3432-485: Is another common procedure used to locate voids. It is recommended to do this testing at night as during cooler temperatures, joints open, aggregate interlock diminishes and load deflections are at their highest. Ground penetrating radar pulses electromagnetic waves into the pavement and measures and graphically displays the reflected signal. This can reveal voids and other defects. The epoxy/core test, detects voids by visual and mechanical methods. It consists of drilling

3564-418: Is discovered it is removed, moisture content is managed and replaced with standard fill compacted to meet the design requirements (generally 90–95% relative compaction). Blasting is not frequently used to excavate the roadbed as the intact rock structure forms an ideal road base. When a depression must be filled to come up to the road grade the native bed is compacted after the topsoil has been removed. The fill

3696-451: Is made by the "compacted layer method" where a layer of fill is spread then compacted to specifications, under saturated conditions. The process is repeated until the desired grade is reached. General fill material should be free of organics , meet minimum California bearing ratio (CBR) results and have a low plasticity index . The lower fill generally comprises sand or a sand-rich mixture with fine gravel, which acts as an inhibitor to

3828-692: Is partially sheltered by the Mendip Hills, it is exposed to the Severn Estuary and the Bristol Channel . Rain is fairly evenly distributed throughout the year, with autumn and winter the wetter seasons. The Atlantic Ocean influences Bristol's weather, keeping its average temperature above freezing throughout the year, but winter frosts are frequent and snow occasionally falls from early November to late April. Summers are warm and drier, with variable sunshine, rain and clouds, and spring weather

3960-571: Is primarily due to environmental effects such as frost heaves , thermal cracking and oxidation often contribute, however accumulated damage from vehicles also contributes. According to a series of experiments carried out in the late 1950s, called the AASHO Road Test , it was empirically determined that the effective damage done to the road is roughly proportional to the fourth power of axle weight . A typical tractor-trailer weighing 80,000 pounds (36.287 t ) with 8,000 pounds (3.629 t) on

4092-459: Is represented by 5 constituencies, East , North East , North West , South , and Central . The city has a tradition of political activism. Edmund Burke , MP for the Bristol constituency for six years beginning in 1774, insisted that he was a Member of Parliament first and a representative of his constituents' interests second. Women's-rights advocate Emmeline Pethick-Lawrence (1867–1954)

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4224-522: Is some ambiguity between the terms highway and road . For the purposes of the English law , Highways Act 1980 , which covers England and Wales but not Scotland or Northern Ireland , road is "any length of highway or of any other road to which the public has access, and includes bridges over which a road passes". This includes footpaths, bridleways and cycle tracks, and also road and driveways on private land and many car parks. Vehicle Excise Duty ,

4356-588: Is sometimes considered the first person to bring post-Roman science to road building. A Frenchman from an engineering family, he worked paving roads in Paris from 1757 to 1764. As chief engineer of road construction of Limoges , he had opportunity to develop a better and cheaper method of road construction. In 1775, Tresaguet became engineer-general and presented his answer for road improvement in France, which soon became standard practice there. Trésaguet had recommended

4488-410: Is taken to preserve reference Benchmarks Roads are designed and built for primary use by vehicular and pedestrian traffic. Storm drainage and environmental considerations are a major concern. Erosion and sediment controls are constructed to prevent detrimental effects. Drainage lines are laid with sealed joints in the road easement with runoff coefficients and characteristics adequate for

4620-546: Is the native material underneath a constructed road. Road construction requires the creation of an engineered continuous right-of-way or roadbed , overcoming geographic obstacles and having grades low enough to permit vehicle or foot travel , and may be required to meet standards set by law or official guidelines. The process is often begun with the removal of earth and rock by digging or blasting, construction of embankments , bridges and tunnels , and removal of vegetation (this may involve deforestation ) and followed by

4752-1035: Is unsettled. The weather stations nearest Bristol for which long-term climate data are available are Long Ashton (about 5 mi (8 km) south west of the city centre) and Bristol Weather Station, in the city centre. Data collection at these locations ended in 2002 and 2001, respectively, and following the closure of Filton Airfield, Almondsbury is the nearest weather station to the city. Temperatures at Long Ashton from 1959 to 2002 ranged from 33.5 °C (92.3 °F) in July 1976 to −14.4 °C (6.1 °F) in January 1982. Monthly high temperatures since 2002 at Filton exceeding those recorded at Long Ashton include 25.7 °C (78.3 °F) in April 2003, 34.5 °C (94.1 °F) in July 2006 and 26.8 °C (80.2 °F) in October 2011. The lowest recent temperature at Filton

4884-596: Is unusual among major British towns and cities in its larger black than Asian population. These statistics apply to the Bristol Unitary Authority area, excluding areas of the urban area (2006 estimated population 587,400) in South Gloucestershire, Bath and North East Somerset (BANES) and North Somerset—such as Kingswood, Mangotsfield, Filton and Warmley. 56.2% of the 209,995 Bristol residents who are employed commute to work using either

5016-559: Is usually stripped and stockpiled nearby for rehabilitation of newly constructed embankments along the road. Stumps and roots are removed and holes filled as required before the earthwork begins. Final rehabilitation after road construction is completed will include seeding, planting, watering and other activities to reinstate the area to be consistent with the untouched surrounding areas. Processes during earthwork include excavation, removal of material to spoil, filling, compacting, construction and trimming. If rock or other unsuitable material

5148-921: The Ashton Court Estate , South Bristol crematorium and cemetery, High Ridge common and Whitchurch, with a further area around Frenchay Farm. The belt extends outside the city boundaries into surrounding counties and districts, for several miles in places, to afford a protection from urban sprawl to surrounding villages and towns. According to the 2011 census , 84% of the population was White (77.9% White British , 0.9% White Irish , 0.1% Gypsy or Irish Travellers and 5.1% Other White ); 3.6% mixed-race (1.7% white-and-black Caribbean, 0.4% white-and-black African, 0.8% white and Asian and 0.7% other mixed); 5.5% Asian (1.6% Pakistani , 1.5% Indian , 0.9% Chinese , 0.5% Bangladeshi , and 1% other Asian); 6% Black (2.8% African, 1.6% Caribbean , 1.6% Other Black ), 0.3% Arab and 0.6% with other heritage. Bristol

5280-641: The Chesapeake Bay to Wheeling on the Ohio River . Before it was macadamized, stagecoaches travelling the Hagerstown to Boonsboro road in the winter had taken 5 to 7 hours to cover the 10-mile (16 km) stretch. This road was completed in 1823, using McAdam's road techniques, except that the finished road was compacted with a cast iron roller instead of relying on road traffic for compaction. The second American road built using McAdam principles

5412-534: The IRA , in 1974 and again in 1978 . The 20th-century relocation of the docks to Avonmouth Docks and Royal Portbury Dock , 7 mi (11 km) downstream from the city centre, has allowed the redevelopment of the old dock area (the Floating Harbour). Although the docks' existence was once in jeopardy (since the area was seen as a derelict industrial site), the inaugural 1996 International Festival of

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5544-453: The Kennet and Avon Canal , which had fully opened in 1810 as the main route for the transport of goods between Bristol and London. Competition from Liverpool (beginning around 1760), disruptions of maritime commerce due to war with France (1793) and the abolition of the slave trade (1807) contributed to Bristol's failure to keep pace with the newer manufacturing centres of Northern England and

5676-644: The Levallois technique , indicate the presence of Neanderthals in the Shirehampton and St Annes areas of Bristol during the Middle Palaeolithic . Iron Age hill forts near the city are at Leigh Woods and Clifton Down , on the side of the Avon Gorge , and on Kings Weston Hill near Henbury . A Roman settlement, Abona, existed at what is now Sea Mills (connected to Bath by

5808-578: The Old English Brycgstow , meaning "assembly place by the bridge" or simply "site of the bridge", presumably in reference to a crossing over the Avon. The final l is an unetymological addition that first appears in the 12th century. An older form of the name survives as the surname Bristow , which is derived from the city. Archaeological finds, including flint tools believed to be between 300,000 and 126,000   years old made with

5940-558: The West Midlands . The tidal Avon Gorge, which had secured the port during the Middle Ages, had become a liability. An 1804–09 plan to improve the city's port with a floating harbour designed by William Jessop was a costly error, requiring high harbour fees. During the 19th century, Samuel Plimsoll , known as "the sailor's friend", campaigned to make the seas safer; shocked by overloaded vessels, he successfully fought for

6072-402: The confluence of the rivers Frome and Avon. Bristol received a royal charter in 1155 and was historically divided between Gloucestershire and Somerset until 1373 when it became a county corporate . From the 13th to the 18th century, Bristol was among the top three English cities, after London, in tax receipts. A major port , Bristol was a starting place for early voyages of exploration to

6204-406: The land zoning and storm water system. Drainage systems must be capable of carrying the ultimate design flow from the upstream catchment with approval for the outfall from the appropriate authority to a watercourse , creek , river or the sea for drainage discharge. A borrow pit (source for obtaining fill, gravel, and rock) and a water source should be located near or in reasonable distance to

6336-453: The water table enabled rain water to run off into ditches on either side. Size of stones was central to McAdam's road building theory. The lower 8 in (20 cm) road thickness was restricted to stones no larger than 3 inches (7.5 cm). The upper 2-inch-thick (5 cm) layer of stones was limited to stones 2 centimetres ( 3 ⁄ 4  in) in diameter; these were checked by supervisors who carried scales. A workman could check

6468-620: The 1640's, during the English Civil War , the city was occupied by Royalists , who built the Royal Fort House on the site of an earlier Parliamentarian stronghold. Fishermen from Bristol, who had fished the Grand Banks of Newfoundland since the 16th century, began settling Newfoundland permanently in larger numbers during the 17th century, establishing colonies at Bristol's Hope and Cuper's Cove . Growth of

6600-631: The 16th century, Bristol merchants concentrated on developing trade with Spain and its American colonies. This included the smuggling of prohibited goods, such as food and guns, to Iberia during the Anglo-Spanish War (1585–1604) . Bristol's illicit trade grew enormously after 1558, becoming integral to its economy. The original Diocese of Bristol was founded in 1542, when the former Abbey of St. Augustine (founded by Robert Fitzharding four hundred years earlier) became Bristol Cathedral . Bristol also gained city status that year. In

6732-637: The Future 's 2008 Sustainable Cities Index. Local initiatives include Sustrans (creators of the National Cycle Network , founded as Cyclebag in 1977) and Resourcesaver, a non-profit business established in 1988 by Avon Friends of the Earth. In 2014 The Sunday Times named it as the best city in Britain in which to live. The city received the 2015 European Green Capital Award , becoming

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6864-603: The New World. At the height of the Bristol slave trade , from 1700 to 1807, more than 2,000 slave ships carried an estimated 500,000 people from Africa to slavery in the Americas. The Port of Bristol has since moved from Bristol Harbour in the city centre to the Severn Estuary at Avonmouth and Royal Portbury Dock . The city's modern economy is built on the creative media, electronics and aerospace industries;

6996-628: The Sea held in and around the docks affirmed the area as a leisure asset of the city. From 2018, there were lively discussions about a new explicative plaque under a commemorative statue of one of the city's major benefactors in the 17th and 18th centuries. The plaque was meant to replace an original which made no reference to Edward Colston 's past with the Royal African Company and the Bristol Slave Trade . On 7 June 2020

7128-422: The ability to flow into or expand to fill small voids. Colloidal mixing equipment is necessary to use the pozzolan-cement grouts. The contractor must place the grout using a positive-displacement injection pump or a non-pulsing progressive cavity pump. A drill is also necessary but it must produce a clean hole with no surface spalling or breakouts. The injection devices must include a grout packer capable of sealing

7260-454: The advent of motor vehicles , dust became a serious problem on macadam roads. The area of low air pressure created under fast-moving vehicles sucked dust from the road surface, creating dust clouds and a gradual unraveling of the road material. This problem was approached by spraying tar on the surface to create tar-bound macadam. In 1902 a Swiss doctor, Ernest Guglielminetti , came upon the idea of using tar from Monaco 's gasworks for binding

7392-551: The aggregates are thoroughly mixed with the binding material and the mixture is laid all together. While macadam roads have been resurfaced in most developed countries , some are preserved along stretches of roads such as the United States' National Road. Because of the historic use of macadam as a road surface, roads in some parts of the United States (such as parts of Pennsylvania ) are referred to as macadam, even though they might be made of asphalt or concrete . Similarly,

7524-432: The area surrounding the roadside. Previous road builders in Britain ignored drainage problems and Telford's rediscovery of drainage principles was a major contribution to road construction. Notably, around the same time, John Metcalf strongly advocated that drainage was in fact an important factor in road construction and astonished colleagues by building dry roads even through marshland. He accomplished this by incorporating

7656-566: The arrest, trial and subsequent acquittal of a local slaver captain named Kimber. The city was associated with Victorian engineer Isambard Kingdom Brunel , who designed the Great Western Railway between Bristol and London Paddington , two pioneering Bristol-built oceangoing steamships ( SS  Great Britain and SS  Great Western ), and the Clifton Suspension Bridge . The new railway replaced

7788-521: The average US motorist pays about $ 335/year. In contrast, the average motorist pays about $ 171/year in road maintenance taxes (based on 600 gallons/year and $ 0.285/gallon tax). Distress and serviceability loss on concrete roads can be caused by loss of support due to voids beneath the concrete pavement slabs. The voids usually occur near cracks or joints due to surface water infiltration . The most common causes of voids are pumping, consolidation, subgrade failure and bridge approach failure. Slab stabilization

7920-560: The castle. A third bomb-damaged church nearby, St Nicholas was restored and after a period as a museum has now re-opened as a church. It houses a 1756 William Hogarth triptych painted for the high altar of St Mary Redcliffe . The church also has statues of King Edward I (moved from Arno's Court Triumphal Arch ) and King Edward III (taken from Lawfords' Gate in the city walls when they were demolished about 1760), and 13th-century statues of Robert, 1st Earl of Gloucester (builder of Bristol Castle ) and Geoffrey de Montbray (who built

8052-423: The city and trade came with the rise of England's American colonies in the 17th century. Bristol's location on the west side of Great Britain gave its ships an advantage in sailing to and from the New World, and the city's merchants made the most of it, with the city becoming one of the two leading outports in all of England by the middle of the 18th century. Bristol was the slave capital of England: In 1755, it had

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8184-551: The city's walls) from Bristol's Newgate . The rebuilding of Bristol city centre was characterised by 1960s and 1970s skyscrapers , mid-century modern architecture and road building . Beginning in the 1980s some main roads were closed , the Georgian-era Queen Square and Portland Square were restored, the Broadmead shopping area regenerated, and one of the city centre's tallest mid-century towers

8316-1111: The city, and its surrounding land has been protected from development as The Downs and Leigh Woods. The Avon estuary and the gorge form the county boundary with North Somerset , and the river flows into the Severn Estuary at Avonmouth . A smaller gorge, cut by the Hazel Brook which flows into the River Trym , crosses the Blaise Castle estate in northern Bristol. Bristol is sometimes described, by its inhabitants, as being built on seven hills, like Rome. From 18th-century guidebooks, these 7 hills were known as simply Bristol (the Old Town), Castle Hill, College Green, Kingsdown, St Michaels Hill, Brandon Hill and Redcliffe Hill. Other local hills include Red Lion Hill, Barton Hill , Lawrence Hill , Black Boy Hill, Constitution Hill, Staple Hill , Windmill Hill , Malborough Hill, Nine Tree Hill, Talbot, Brook Hill and Granby Hill. Bristol

8448-663: The city-centre docks have been redeveloped as cultural and heritage centres. There are a variety of artistic and sporting organisations and venues including the Royal West of England Academy , the Arnolfini , Ashton Gate and the Memorial Stadium . The city has two universities; the University of Bristol and the University of the West of England (UWE Bristol). It is connected to the world by Bristol Airport ; to

8580-583: The city-council boundary, such as Kingswood , Mangotsfield , Stoke Gifford , Winterbourne , Almondsbury , Easton in Gordano , Whitchurch village, Filton , Patchway and Bradley Stoke , but excludes undeveloped areas within that boundary. Bristol lies within a limestone area running from the Mendip Hills in the south to the Cotswolds in the northeast. The rivers Avon and Frome cut through

8712-442: The clean stone to bind the road. The action of the road traffic would cause the broken stone to combine with its own angles, merging into a level, solid surface that would withstand weather or traffic. The first macadam road built in the United States was constructed between Hagerstown and Boonsboro, Maryland , and was named at the time Boonsborough Turnpike Road. This was the last section of unimproved road between Baltimore on

8844-450: The council. Between 2012 and 2024, the council was led by a directly elected mayor, the Mayor of Bristol . The post was abolished following a 2022 referendum, in which voters chose to replace it with a council committee system. The lord mayor of Bristol is a figurehead elected each May by the city council. The lord mayor is Councillor Andrew Varney. In the House of Commons , Bristol

8976-519: The country, trading with Ireland, Iceland and Gascony . It was the starting point for many voyages, including Robert Sturmy 's (1457–58) unsuccessful attempt to break the Italian monopoly of Eastern Mediterranean trade. New exploration voyages were launched by Venetian John Cabot , who in 1497 made landfall in North America. A 1499 voyage, led by merchant William Weston of Bristol, was

9108-551: The definition of a road is broad in common law where the statutory definition includes areas the public has access to, by right or not. Beaches, publicly accessible car parks and yards (even if privately owned), river beds, road shoulders (verges), wharves and bridges are included. However, the definition of a road for insurance purposes may be restricted to reduce risk. In the United Kingdom The Highway Code details rules for "road users", but there

9240-465: The design structural capacity, stop erosion or eliminate faulting. It does, however, restore the slab support, therefore, decreasing deflections under the load. Stabilization should only be performed at joints and cracks where the loss of support exists. Visual inspection is the simplest manner to find voids. Signs that repair is needed are transverse joint faulting, corner breaks and shoulder drop off and lines at or near joints and cracks. Deflection testing

9372-412: The dust. Later a mixture of coal tar and ironworks slag , patented by Edgar Purnell Hooley as tarmac , was introduced. A more durable road surface (modern mixed asphalt pavement), sometimes referred to in the U.S. as blacktop, was introduced in the 1920s. Instead of laying the stone and sand aggregates on the road and then spraying the top surface with binding material, in the asphalt paving method

9504-599: The early 1900s by the Royal Edward Dock. Another new dock, the Royal Portbury Dock , opened across the river from Avonmouth during the 1970s. As air travel grew in the first half of the century, aircraft manufacturers built factories. The unsuccessful Bristol International Exhibition was held on Ashton Meadows in the Bower Ashton area in 1914. After the premature closure of the exhibition

9636-539: The enslaved captives were transported across the Atlantic to the Americas in the Middle Passage under brutal conditions. Plantation goods such as sugar, tobacco, rum, rice, cotton and a few slaves (sold to the aristocracy as house servants) returned across the Atlantic to England. Some household slaves were baptised in the hope this would lead them to be freed. The Somersett Case of 1772 clarified that slavery

9768-521: The first UK city to receive this award. In 2019 Bristol City Council voted in favour of banning all privately owned diesel cars from the city centre. Since then, the plans have been revised in favour of a clean air zone whereby older and more polluting vehicles will be charged to drive through the city centre. The Clean Air Zone came into effect in November 2022. The city has green belt mainly along its southern fringes, taking in small areas within

9900-511: The first expedition commanded by an Englishman to North America . During the first decade of the 16th century Bristol's merchants undertook a series of exploration voyages to North America and even founded a commercial organisation, 'The Company Adventurers to the New Found Land', to assist their endeavours. However, they seem to have lost interest in North America after 1509, having incurred great expenses and made little profit. During

10032-441: The first pathways were the trails made by animals has not been universally accepted; in many cases animals do not follow constant paths. Some believe that some roads originated from following animal trails. The Icknield Way may exemplify this type of road origination, where human and animal both selected the same natural line. By about 10,000 BC human travelers used rough roads/pathways. In transport engineering , subgrade

10164-416: The functional condition of the road while reducing the need for routing maintenance, leading to extended service life without increasing structural capacity. Older concrete pavements that develop faults can be repaired with a dowel bar retrofit , in which slots are cut in the pavement at each joint, and dowel bars are placed in the slots, which are then filled with concrete patching material. This can extend

10296-464: The growth of plants or other vegetable matter. The compacted fill also serves as lower-stratum drainage. Select second fill ( sieved ) should be composed of gravel , decomposed rock or broken rock below a specified particle size and be free of large lumps of clay . Sand clay fill may also be used. The roadbed must be "proof rolled" after each layer of fill is compacted. If a roller passes over an area without creating visible deformation or spring

10428-404: The highway system from traffic collisions. On neighborhood roads traffic calming , safety barriers , pedestrian crossings and cycle lanes can help protect pedestrians, cyclists, and drivers. Lane markers in some countries and states are marked with Cat's eyes or Botts dots. Botts dots are not used where it is icy in the winter, because frost and snowplows can break the glue that holds them to

10560-461: The history of the Irish slave trade from Bristol, which he provocatively claimed continued into the reign of Henry VII . Hannah More , originally from Bristol, and a good friend of both Wilberforce and Clarkson, published "Slavery, A Poem" in 1788, just as Wilberforce began his parliamentary campaign. His major speech on 2 April 1792 likewise described the Bristol slave trade specifically, and led to

10692-580: The hole. The injection device must also have a return hose or a fast-control reverse switch, in case workers detect slab movement on the uplift gauge. The uplift beam helps to monitor the slab deflection and has to have sensitive dial gauges. Also called joint and crack repair, this method's purpose is to minimize infiltration of surface water and incompressible material into the joint system. Joint sealants are also used to reduce dowel bar corrosion in concrete pavement restoration techniques. Successful resealing consists of old sealant removal, shaping and cleaning

10824-539: The import and processing of tobacco flourished with the expansion of the W.D. & H.O. Wills business. Supported by new industry and growing commerce, Bristol's population (66,000 in 1801), quintupled during the 19th century, resulting in the creation of new suburbs such as Clifton and Cotham . These provide architectural examples from the Georgian to the Regency style, with many fine terraces and villas facing

10956-471: The joints were broken in the method of conventional brickwork but with the smallest faces of the pitcher forming the upper and lower surfaces. Broken stone was wedged into the spaces between the tapered perpendicular faces to provide the layer with good lateral control. Telford kept the natural formation level and used masons to camber the upper surface of the blocks. He placed a 6-inch (15 cm) layer of stone no bigger than 2.4 in (6 cm) on top of

11088-459: The larger stones in the road structure from iron wheels and horse hooves. To keep the running surface level with the countryside, this road was put in a trench, which created drainage problems. These problems were addressed by changes that included digging deep side ditches, making the surface as solid as possible, and constructing the road with a difference in elevation (height) between the two edges, that difference being referred to interchangeably as

11220-643: The largest number of slave traders in the country with 237, as against London's 147. It was a major supplier of slaves to South Carolina before 1750. The 18th century saw an expansion of Bristol's population (45,000 in 1750) and its role in the Atlantic trade in Africans taken for slavery to the Americas. Bristol and later Liverpool became centres of the Triangular Trade . Manufactured goods were shipped to West Africa and exchanged for Africans;

11352-404: The laying of pavement material. A variety of road building equipment is employed in road building. After design, approval , planning , legal, and environmental considerations have been addressed alignment of the road is set out by a surveyor . The radii and gradient are designed and staked out to best suit the natural ground levels and minimize the amount of cut and fill. Great care

11484-530: The life of the concrete pavement for 15 years. Failure to maintain roads properly can create significant costs to society. A 2009 report released by the American Association of State Highway and Transportation Officials estimated that about 50% of the roads in the US are in bad condition, with urban areas worse. The report estimates that urban drivers pay an average of $ 746/year on vehicle repairs while

11616-609: The lifespan of their roads. Technically advanced agencies monitor the road network surface condition with sophisticated equipment such as laser/inertial profilometers . These measurements include road curvature , cross slope , asperity , roughness , rutting and texture . Software algorithms use this data to recommend maintenance or new construction. Maintenance treatments for asphalt concrete generally include thin asphalt overlays, crack sealing, surface rejuvenating, fog sealing, micro milling or diamond grinding and surface treatments . Thin surfacing preserves, protects and improves

11748-490: The limestone to the underlying clay, creating Bristol's characteristically hilly landscape. The Avon flows from Bath in the east, through flood plains and areas which were marshes before the city's growth. To the west the Avon cuts through the limestone to form the Avon Gorge, formed largely by glacial meltwater after the last ice age . The gorge, which helped protect Bristol Harbour, has been quarried for stone to build

11880-673: The most populous city in the region. Built around the River Avon , it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. The county is in the West of England combined authority area, which includes the Greater Bristol area ( eleventh most populous urban area in the United Kingdom) and nearby places such as Bath . Iron Age hillforts and Roman villas were built near

12012-495: The neighbouring village of Kingswood , often in the open air. Wesley published a pamphlet on slavery, titled Thoughts Upon Slavery, in 1774 and the Society of Friends began lobbying against slavery in Bristol in 1783. The city's scions remained nonetheless strongly anti-abolitionist. Thomas Clarkson came to Bristol to study the slave trade and gained access to the Society of Merchant Venturers records. One of his contacts

12144-515: The new carriageway is not always constructed directly alongside the existing carriageway. Roads that are intended for use by a particular mode of transport can be reallocated for another mode of transport, i.e. by using traffic signs . For instance, in the ongoing road space reallocation effort, some roads (particularly in city centers) which are intended for use by cars are increasingly being repurposed for cycling and/or walking . Like all structures, roads deteriorate over time. Deterioration

12276-477: The number of road traffic casualties from traffic collisions . In their World report on road traffic injury prevention report, the World Health Organization (WHO) identify speed control as one of various interventions likely to contribute to a reduction in road casualties. Road conditions are the collection of factors describing the ease of driving on a particular stretch of road, or on

12408-506: The owner may have excessive repair and rehabilitation costs. Some asphalt pavements are designed as perpetual pavements with an expected structural life in excess of 50 years. Many asphalt pavements built over 35 years ago, despite not being specifically designed as a perpetual pavement, have remained in good condition long past their design life. Many concrete pavements built since the 1950s have significantly outlived their intended design lives. Some roads like Chicago 's Wacker Drive ,

12540-418: The pavement performance, reduce construction costs and decrease maintenance. The completed roadway is finished by paving or left with a gravel or other natural surface. The type of road surface is dependent on economic factors and expected usage. Safety improvements such as traffic signs , crash barriers , raised pavement markers and other forms of road surface marking are installed. According to

12672-513: The presence or absence of a made road has nothing to do with the distinction. Another legal view is that while a highway historically included footpaths , bridleways , driftways, etc., it can now be used to mean those ways that allow the movement of motor vehicles , and the term rights of way can be used to cover the wider usage. In the United States, laws distinguish between public roads , which are open to public use, and private roads , which are privately controlled. The assertion that

12804-477: The public so that drivers going through a particular area can be aware of hazards that may exist in that area. News agencies, in turn, rely on tips from area residents with respect to certain aspects of road conditions in their coverage area. Bristol Bristol ( / ˈ b r ɪ s t əl / ) is a city , unitary authority area and ceremonial county in South West England ,

12936-418: The reservoir, installing the backer rod and installing the sealant. Sawing, manual removal, plowing and cutting are methods used to remove the old sealant. Saws are used to shape the reservoir. When cleaning the reservoir, no dust, dirt or traces of old sealant should remain. Thus, it is recommended to water wash, sand-blast and then air blow to remove any sand, dirt or dust. The backer rod installation requires

13068-663: The rest of the Great Britain via Bristol Temple Meads and Bristol Parkway mainline rail stations; by road by both the south-west to West Midlands M5 and the London to South Wales M4 (which connect to the city centre by the Portway and M32 ). Bristol was named the best city in Britain in which to live in 2014 and 2017; it won the European Green Capital Award in 2015. The name derives from

13200-494: The road conditions". Specific aspects of road conditions can be of particular importance for particular purposes. For example, for autonomous vehicles such as self-driving cars , significant road conditions can include "shadowing and lighting changes, road surface texture changes, and road markings consisting of circular reflectors, dashed lines, and solid lines". Various government agencies and private entities, including local news services, track and report on road conditions to

13332-399: The road construction area may be marked for retention. These protected trees should not have the topsoil within the area of the tree's drip line removed and the area should be kept clear of construction material and equipment. Compensation or replacement may be required if a protected tree is damaged. Much of the vegetation may be mulched and put aside for use during reinstatement. The topsoil

13464-512: The road construction site. Approval from local authorities may be required to draw water or for working (crushing and screening) of materials for construction needs. The topsoil and vegetation is removed from the borrow pit and stockpiled for subsequent rehabilitation of the extraction area. Side slopes in the excavation area not steeper than one vertical to two horizontal for safety reasons. Old road surfaces, fences, and buildings may need to be removed before construction can begin. Trees in

13596-477: The road problems of the French could be avoided by using cubical stone blocks. Telford used roughly 12 in × 10 in × 6 in (30 cm × 25 cm × 15 cm) partially shaped paving stones (pitchers), with a slight flat face on the bottom surface. He turned the other faces more vertically than Tresaguet's method. The longest edge was arranged crossways to the traffic direction, and

13728-617: The road's camber or cross slope . Thomas Telford , born in Dumfriesshire , Scotland , was a surveyor and engineer who applied Tresaguet's road building theories. In 1801 Telford worked for the Commission of Highland Roads and Bridges . He became director of the Holyhead Road Commission between 1815 and 1830. Telford extended Tresaguet's theories but emphasized high-quality stone. He recognized that some of

13860-473: The road, although they can be embedded in short, shallow trenches carved in the roadway, as is done in the mountainous regions of California. For major roads risk can be reduced by providing limited access from properties and local roads, grade separated junctions and median dividers between opposite-direction traffic to reduce the likelihood of head-on collisions. The placement of energy attenuation devices (e.g. guardrails, wide grassy areas, sand barrels)

13992-492: The road, and at right angles to it. In the early 19th century, the romantic medieval gothic style appeared, partially as a reaction against the symmetry of Palladianism , and can be seen in buildings such as the Bristol City Museum and Art Gallery , the Royal West of England Academy , and The Victoria Rooms . Riots broke out in 1793 and 1831; the first over the renewal of tolls on Bristol Bridge, and

14124-404: The roads of a particular locality, including the quality of the pavement surface , potholes , road markings, and weather . It has been reported that "[p]roblems of transportation participants and road conditions are the main factors that lead to road traffic accidents". It has further been specifically noted that "weather conditions and road conditions are interlinked as weather conditions affect

14256-435: The roads. His legacy lies in his advocacy of effective road maintenance and management. He advocated a central road authority with trained professional officials who could be paid a salary that would keep them from corruption. These professionals could give their entire time to these duties and be held responsible for their actions. McAdam's road building technology was applied to roads by other engineers. One of these engineers

14388-430: The rock foundation. To finish the road surface he covered the stones with a mixture of gravel and broken stone. This structure came to be known as "Telford pitching." Telford's road depended on a resistant structure to prevent water from collecting and corroding the strength of the pavement. Telford raised the pavement structure above ground level whenever possible. Where the structure could not be raised, Telford drained

14520-462: The second against the rejection of the second Reform Bill by the House of Lords . The population by 1841 had reached 140,158. The Diocese of Bristol had undergone several boundary changes by 1897 when it was "reconstituted" into the configuration which has lasted into the 21st century. From a population of about 330,000 in 1901, Bristol grew steadily during the 20th century, peaking at 428,089 in 1971. Its Avonmouth docklands were enlarged during

14652-406: The section is deemed to comply. Geosynthetics such as geotextiles , geogrids , and geocells are frequently used in the various pavement layers to improve road quality. These materials and methods are used in low-traffic private roadways as well as public roads and highways. Geosynthetics perform four main functions in roads: separation, reinforcement, filtration, and drainage; which increase

14784-517: The site was used, until 1919, as barracks for the Gloucestershire Regiment during World War I . Bristol was heavily damaged by Luftwaffe raids during World War II ; about 1,300 people living or working in the city were killed and nearly 100,000 buildings were damaged, at least 3,000 beyond repair. The original central shopping area, near the bridge and castle, is now a park containing two bombed churches and fragments of

14916-437: The slab. The grout can fill small voids beneath the slab and/or sub-base. The grout also displaces free water and helps keep water from saturating and weakening support under the joints and slab edge after stabilization is complete. The three steps for this method after finding the voids are locating and drilling holes, grout injection and post-testing the stabilized slabs. Slab stabilization does not correct depressions, increase

15048-403: The socioeconomic circumstances of the city's Afro-Caribbean residents. Local support of fair trade was recognised in 2005, when Bristol became a fairtrade zone . Bristol is both a city and a county, since King Edward III granted it a county charter in 1373. The county was expanded in 1835 to include suburbs such as Clifton , and it was named a county borough in 1889 when that designation

15180-483: The steer axle and 36,000 pounds (16.329 t) on both of the tandem axle groups is expected to do 7,800 times more damage than a passenger vehicle with 2,000 pounds (0.907 t) on each axle. Potholes on roads are caused by rain damage and vehicle braking or related construction work. Pavements are designed for an expected service life or design life . In some parts of the United Kingdom the standard design life

15312-417: The stone size himself by seeing if the stone would fit into his mouth. The importance of the 2 cm stone size was that the stones needed to be much smaller than the four-inch (10 cm) width of the iron carriage wheels that travelled on the road. McAdam believed that the "proper method" of breaking stones for utility and rapidity was accomplished by people sitting down and using small hammers, breaking

15444-403: The stones so that none of them was larger than six ounces (170 g) in weight. He also wrote that the quality of the road would depend on how carefully the stones were spread on the surface over a sizeable space, one shovelful at a time. McAdam directed that no substance that would absorb water and affect the road by frost should be incorporated into the road. Neither was anything to be laid on

15576-692: The term "tarmac" is sometimes colloquially applied to asphalt roads or aircraft runways . Road There are many types of roads , including parkways , avenues , controlled-access highways (freeways, motorways, and expressways), tollways , interstates , highways , thoroughfares , and local roads. The primary features of roads include lanes , sidewalks (pavement), roadways (carriageways), medians , shoulders , verges , bike paths (cycle paths), and shared-use paths . Historically many roads were simply recognizable routes without any formal construction or some maintenance. The Organization for Economic Co-operation and Development (OECD) defines

15708-622: The town had one of the strongest castles in southern England . Bristol was the place of exile for Diarmait Mac Murchada , the Irish king of Leinster , after being overthrown. The Bristol merchants subsequently played a prominent role in funding Richard Strongbow de Clare and the Norman invasion of Ireland . The port developed in the 11th century around the confluence of the Rivers Frome and Avon , adjacent to Bristol Bridge just outside

15840-432: The town walls. By the 12th century, there was an important Jewish community in Bristol which survived through to the late 13th century when all Jews were expelled from England. The stone bridge built in 1247 was replaced by the current bridge during the 1760s. The town incorporated neighbouring suburbs and became a county in 1373, the first town in England to be given this status. During this period, Bristol became

15972-540: The western Severn Estuary ending at (but not including) the islands of Flat Holm (in Cardiff , Wales) and Steep Holm . This "seaward extension" can be traced back to the original boundary of the County of Bristol laid out in the charter granted to the city by Edward III in 1373. The Office for National Statistics (ONS) has defined a Bristol Urban Area , which includes developed areas adjoining Bristol but outside

16104-404: The width of a wheel made for a good running surface. The small surface stones also provided low stress on the road, so long as it could be kept reasonably dry. Unlike Telford and other road builders of the time, McAdam laid his roads almost level. His 30-foot-wide (9.1 m) road required a rise of only 3 inches (7.6 cm) from the edges to the centre. Cambering and elevation of the road above

16236-449: Was Richard Edgeworth , who filled the gaps between the surface stones with a mixture of stone dust and water, providing a smoother surface for the increased traffic using the roads. This basic method of construction is sometimes known as water-bound macadam. Although this method required a great deal of manual labour, it resulted in a strong and free-draining pavement. Roads constructed in this manner were described as "macadamized." With

16368-576: Was born in Bristol, and the left-winger Tony Benn served as MP for Bristol South East in 1950–1960 and again from 1963 to 1983. In 1963 the Bristol Bus Boycott , following the Bristol Omnibus Company 's refusal to hire black drivers and conductors, drove the passage of the UK's 1965 Race Relations Act . The 1980 St. Pauls riot protested against racism and police harassment and showed mounting dissatisfaction with

16500-523: Was demolished. Bristol's road infrastructure changed dramatically during the 1960s and 1970s with the development of the M4 and M5 motorways , which meet at the Almondsbury Interchange just north of the city and link Bristol with London (M4 eastbound), Swansea (M4 westbound across the Severn Estuary ), Exeter (M5 southbound) and Birmingham (M5 northbound). Bristol was bombed twice by

16632-472: Was illegal in England. At the height of the Bristol slave trade from 1700 to 1807, more than 2,000 slave ships carried a conservatively estimated 500,000 people from Africa to slavery in the Americas. In 1739, John Wesley founded the first Methodist chapel, the New Room , in Bristol. Wesley, along with his brother Charles Wesley and George Whitefield , preached to large congregations in Bristol and

16764-633: Was introduced. On 1 April 1974, Bristol became a local government district of the county of Avon . On 1 April 1996, Avon was abolished and Bristol became a unitary authority . The former Avon area, called Greater Bristol by the Government Office of the South West (now abolished) and others, refers to the city and the three neighbouring local authorities‍—‌ Bath and North East Somerset , North Somerset and South Gloucestershire previously in Avon. The North Fringe of Bristol ,

16896-615: Was responsible for 149 miles of road. He then put his ideas about road construction into practice, the first 'macadamised' stretch of road being Marsh Road at Ashton Gate, Bristol. He also began to actively propagate his ideas in two booklets called Remarks (or Observations) on the Present System of Roadmaking , (which ran nine editions between 1816 and 1827) and A Practical Essay on the Scientific Repair and Preservation of Public Roads, published in 1819. McAdam's method

17028-423: Was simpler yet more effective at protecting roadways: he discovered that massive foundations of rock upon rock were unnecessary and asserted that native soil alone would support the road and traffic upon it, as long as it was covered by a road crust that would protect the soil underneath from water and wear. An under-layer of small angular broken stones would act as a solid mass. Keeping the surface stones smaller than

17160-472: Was the Cumberland Road which was 73 miles (117 km) long and was completed in 1830 after five years of work. McAdam's renown is his effective and economical construction, which was a great improvement over the methods used by his generation. He emphasised that roads could be constructed for any kind of traffic, and he helped to alleviate the resentment travellers felt toward increasing traffic on

17292-460: Was the owner of the Seven Stars public house , who boarded sailors Clarkson sought to meet. Through these sailors he was able to observe how slaver captains and first mates "plied and stupefied seamen with drink" to sign them up. Other informants included ship surgeons and seamen seeking redress. When William Wilberforce began his parliamentary abolition campaign on 12 May 1788, he recalled

17424-519: Was −10.1 °C (13.8 °F) in December 2010. Although large cities in general experience an urban heat island effect, with warmer temperatures than their surrounding rural areas, this phenomenon is minimal in Bristol. Bristol was ranked as Britain's most sustainable city (based on its environmental performance, quality of life, future-proofing and approaches to climate change, recycling and biodiversity), topping environmental charity Forum for

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