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111-451: Transport infrastructure consists of both fixed installations, including roads , railways , airways , waterways , canals , and pipelines , and terminals such as airports , railway stations , bus stations , warehouses , trucking terminals, refueling depots (including fuel docks and fuel stations ), and seaports . Terminals may be used both for the interchange of passengers and cargo and for maintenance. Means of transport are any of

222-443: A city or village and be named as streets , serving a dual function as urban space easement and route. The most common road vehicle is the automobile; a wheeled passenger vehicle that carries its own motor . Other users of roads include buses , trucks , motorcycles , bicycles , and pedestrians . As of 2010, there were 1.015 billion automobiles worldwide. Road transport offers complete freedom to road users to transfer

333-411: A jet engine , and there is no need for a tail rotor . In high-speed flight the airfoil is stopped in a spanwise position, as the main wing of a three-surface aircraft , and the engine exhausts through an ordinary jet nozzle. Two Boeing X-50 Dragonfly prototypes with a two-bladed rotor were flown from 2003 but the program ended after both had crashed, having failed to transition successfully. In 2013

444-471: A pipe ; most commonly liquid and gases are sent, but pneumatic tubes can also send solid capsules using compressed air. For liquids/gases, any chemically stable liquid or gas can be sent through a pipeline. Short-distance systems exist for sewage , slurry , water , and beer , while long-distance networks are used for petroleum and natural gas . Cable transport is a broad mode where vehicles are pulled by cables instead of an internal power source. It

555-400: 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,

666-411: 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 ,

777-648: A tragedy of the commons , where the flexibility and comfort for the individual deteriorate the natural and urban environment for all. Density of development depends on mode of transport, with public transport allowing for better spatial use. Good land use keeps common activities close to people's homes and places higher-density development closer to transport lines and hubs, to minimize the need for transport. There are economies of agglomeration . Beyond transport, some land uses are more efficient when clustered. Transport facilities consume land, and in cities pavement (devoted to streets and parking) can easily exceed 20 percent of

888-457: 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

999-614: 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

1110-490: A component for the creation of regulation policy by authorities. Transport engineering , a sub-discipline of civil engineering , must take into account trip generation , trip distribution , mode choice , and route assignment , while the operative level is handled through traffic engineering . Because of the negative impacts incurred, transport often becomes the subject of controversy related to choice of mode, as well as increased capacity. Automotive transport can be seen as

1221-570: A consistent distance apart, or gauge . The rails and perpendicular beams are placed on a foundation made of concrete or compressed earth and gravel in a bed of ballast. Alternative methods include monorail and maglev . A train consists of one or more connected vehicles that operate on the rails. Propulsion is commonly provided by a locomotive , that hauls a series of unpowered cars, that can carry passengers or freight. The locomotive can be powered by steam , by diesel , or by electricity supplied by trackside systems . Alternatively, some or all

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1332-419: 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

1443-422: A great impact on the land, and transport is the largest drainer of energy, making transport sustainability a major issue. Due to the way modern cities and communities are planned and operated, a physical distinction between home and work is usually created, forcing people to transport themselves to places of work, study, or leisure, as well as to temporarily relocate for other daily activities. Passenger transport

1554-444: A helicopter – with anti-torque and propulsion for forward flight provided by one or more propellers mounted on short or stub wings. As power is increased to the propeller, less power is required by the rotor to provide forward thrust resulting in reduced pitch angles and rotor blade flapping. At cruise speeds with most or all of the thrust being provided by the propellers, the rotor receives power only sufficient to overcome

1665-414: A helicopter, autogyros and rotor kites do not have an engine powering their rotors, but while an autogyro has an engine providing forward thrust that keeps the rotor turning, a rotor kite has no engine at all, and relies on either being carried aloft and dropped from another aircraft, or by being towed into the air behind a car or boat. A rotary wing is characterised by the number of blades . Typically this

1776-413: 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

1887-404: A person or of cargo may involve one mode or several of the modes, with the latter case being called inter-modal or multi-modal transport. Each mode has its own advantages and disadvantages, and will be chosen on the basis of cost, capability, and route. Governments deal with the way the vehicles are operated, and the procedures set for this purpose, including financing, legalities, and policies. In

1998-428: 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

2109-494: 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

2220-510: 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

2331-524: 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,

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2442-701: A roadway, a terminal, and facilities for parking and maintenance. For rail, pipeline, road, and cable transport, the entire way the vehicle travels must be constructed. Air and watercraft are able to avoid this, since the airway and seaway do not need to be constructed. However, they require fixed infrastructure at terminals. Terminals such as airports, ports, and stations, are locations where passengers and freight can be transferred from one vehicle or mode to another. For passenger transport, terminals are integrating different modes to allow riders, who are interchanging between modes, to take advantage of each mode's benefits. For instance, airport rail links connect airports to

2553-460: A slightly refined type of petroleum called bunker fuel . Some ships, such as submarines , use nuclear power to produce the steam. Recreational or educational craft still use wind power, while some smaller craft use internal combustion engines to drive one or more propellers or, in the case of jet boats, an inboard water jet. In shallow draft areas, hovercraft are propelled by large pusher-prop fans. (See Marine propulsion .) Although it

2664-412: A state of autorotation to develop lift, and an engine-powered propeller , similar to that of a fixed-wing aircraft , to provide thrust. While similar to a helicopter rotor in appearance, the autogyro's rotor must have air flowing up and through the rotor disk in order to generate rotation. Early autogyros resembled the fixed-wing aircraft of the day, with wings and a front-mounted engine and propeller in

2775-429: A tractor configuration to pull the aircraft through the air. Late-model autogyros feature a rear-mounted engine and propeller in a pusher configuration. The autogyro was invented in 1920 by Juan de la Cierva . The autogyro with pusher propeller was first tested by Etienne Dormoy with his Buhl A-1 Autogyro . The rotor of a gyrodyne is normally driven by its engine for takeoff and landing – hovering like

2886-469: A vertical mast to generate lift . The assembly of several rotor blades mounted on a single mast is referred to as a rotor . The International Civil Aviation Organization (ICAO) defines a rotorcraft as "supported in flight by the reactions of the air on one or more rotors". Rotorcraft generally include aircraft where one or more rotors provide lift throughout the entire flight, such as helicopters , autogyros , and gyrodynes . Compound rotorcraft augment

2997-432: 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,

3108-409: Is a key in the value chain in manufacturing. With increased specialization and globalization , production is being located further away from consumption, rapidly increasing the demand for transport. Transport creates place utility by moving the goods from the place of production to the place of consumption. While all modes of transport are used for cargo transport, there is high differentiation between

3219-405: Is a key necessity for specialization —allowing production and consumption of products to occur at different locations. Throughout history, transport has been a spur to expansion; better transport allows more trade and a greater spread of people. Economic growth has always been dependent on increasing the capacity and rationality of transport. But the infrastructure and operation of transport have

3330-433: 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

3441-487: 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

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3552-406: Is also the essence of tourism , a major part of recreational transport. Commerce requires the transport of people to conduct business, either to allow face-to-face communication for important decisions or to move specialists from their regular place of work to sites where they are needed. In lean thinking , transporting materials or work in process from one location to another is seen as one of

3663-485: 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

3774-412: Is between two and six per driveshaft. A rotorcraft may have one or more rotors. Various rotor configurations have been used: Some rotary wing aircraft are designed to stop the rotor for forward flight so that it then acts as a fixed wing. For vertical flight and hovering it spins to act as a rotary wing or rotor, and for forward flight at speed it stops to act as a fixed wing providing some or all of

3885-404: Is by airline, it amounts to forty percent of the value. Time has become especially important in regards to principles such as postponement and just-in-time within the value chain, resulting in a high willingness to pay for quick delivery of key components or items of high value-to-weight ratio. In addition to mail, common items sent by air include electronics and fashion clothing. Transport

3996-427: Is common to watercraft, making the hull a dominant aspect of its construction, maintenance, and appearance. In the 19th century, the first steam ships were developed, using a steam engine to drive a paddle wheel or propeller to move the ship. The steam was produced in a boiler using wood or coal and fed through a steam external combustion engine . Now most ships have an internal combustion engine using

4107-418: 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

4218-407: Is dominated by the automobile and mass transit. The latter consists of buses in rural and small cities, supplemented with commuter rail, trams, and rapid transit in larger cities. Long-haul transport involves the use of the automobile, trains, coaches , and aircraft, the last of which have become predominantly used for the longest, including intercontinental, travel. Intermodal passenger transport

4329-408: Is frequently a benefits shortfall for transport infrastructure projects. Animals used in transportation include pack animals and riding animals . A vehicle is a non-living device that is used to move people and goods. Unlike the infrastructure, the vehicle moves along with the cargo and riders. Unless being pulled/pushed by a cable or muscle-power, the vehicle must provide its own propulsion; this

4440-502: Is heavily subsidized by governments, good planning of transport is essential to make traffic flow and restrain urban sprawl . Human-powered transport, a form of sustainable transport , is the transport of people or goods using human muscle-power, in the form of walking , running , and swimming . Modern technology has allowed machines to enhance human power. Human-powered transport remains popular for reasons of cost-saving, leisure , physical exercise , and environmentalism ; it

4551-451: 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

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4662-475: Is most commonly done through a steam engine , combustion engine , electric motor , jet engine , or rocket , though other means of propulsion also exist. Vehicles also need a system of converting the energy into movement; this is most commonly done through wheels , propellers , and pressure . Vehicles are most commonly staffed by a driver . However, some systems, such as people movers and some rapid transits, are fully automated . For passenger transport,

4773-611: Is most commonly used at steep gradient . Typical solutions include aerial tramways , elevators , and ski lifts ; some of these are also categorized as conveyor transport. Spaceflight is transport outside Earth's atmosphere by means of a spacecraft . It is most frequently used for satellites placed in Earth orbit. However, human spaceflight mission have landed on the Moon and are occasionally used to rotate crew-members to space stations . Uncrewed spacecraft have also been sent to all

4884-411: Is only subject to the owner of the vehicle, who operates the vehicle themselves. For public transport and freight transport, operations are done through private enterprise or by governments . The infrastructure and vehicles may be owned and operated by the same company, or they may be operated by different entities. Traditionally, many countries have had a national airline and national railway . Since

4995-726: Is performed by high-capacity tramways and rapid transits , often making up the backbone of a city's public transport. Freight trains traditionally used box cars , requiring manual loading and unloading of the cargo . Since the 1960s, container trains have become the dominant solution for general freight, while large quantities of bulk are transported by dedicated trains. A road is an identifiable route , way, or path between two or more places . Roads are typically smoothed, paved , or otherwise prepared to allow easy travel; though they need not be, and historically many roads were simply recognizable routes without any formal construction or maintenance . In urban areas , roads may pass through

5106-571: 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

5217-436: Is slow compared to other transport, modern sea transport is a highly efficient method of transporting large quantities of goods. Commercial vessels , nearly 35,000 in number, carried 7.4 billion tons of cargo in 2007. Transport by water is significantly less costly than air transport for transcontinental shipping ; short sea shipping and ferries remain viable in coastal areas. Pipeline transport sends goods through

5328-522: 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 ,

5439-441: Is sometimes the only type available, especially in underdeveloped or inaccessible regions. Although humans are able to walk without infrastructure, the transport can be enhanced through the use of roads, especially when using the human power with vehicles, such as bicycles and inline skates . Human-powered vehicles have also been developed for difficult environments, such as snow and water, by watercraft rowing and skiing ; even

5550-410: 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

5661-546: 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

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5772-559: 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

5883-439: Is where a journey is performed through the use of several modes of transport; since all human transport normally starts and ends with walking, all passenger transport can be considered intermodal. Public transport may also involve the intermediate change of vehicle, within or across modes, at a transport hub , such as a bus or railway station . Taxis and buses can be found on both ends of the public transport spectrum. Buses are

5994-406: 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

6105-609: The rocket . Commercial jets can reach up to 955 kilometres per hour (593 mph), single-engine aircraft 555 kilometres per hour (345 mph). Aviation is able to quickly transport people and limited amounts of cargo over longer distances, but incurs high costs and energy use; for short distances or in inaccessible places, helicopters can be used. As of April 28, 2009, The Guardian article notes that "the WHO estimates that up to 500,000 people are on planes at any time." Land transport covers all land-based transport systems that provide for

6216-488: The 1980s, many of these have been privatized . International shipping remains a highly competitive industry with little regulation, but ports can be public-owned. As the population of the world increases, cities grow in size and population—according to the United Nations, 55% of the world's population live in cities, and by 2050 this number is expected to rise to 68%. Public transport policy must evolve to meet

6327-570: The US Naval Research Laboratory (NRL) published a vertical-to-horizontal flight transition method and associated technology, patented December 6, 2011, which they call the Stop-Rotor Rotary Wing Aircraft. The Australian company StopRotor Technology Pty Ltd has developed a prototype Hybrid RotorWing (HRW) craft. The design uses high alpha airflow to provide a symmetrical airflow across all

6438-422: 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

6549-428: The air can be entered with human-powered aircraft . Animal-powered transport is the use of working animals for the movement of people and commodities. Humans may ride some of the animals directly, use them as pack animals for carrying goods, or harness them, alone or in teams , to pull sleds or wheeled vehicles . A fixed-wing aircraft , commonly called an airplane, is a heavier-than-air craft where movement of

6660-426: The air in relation to the wings is used to generate lift. The term is used to distinguish this from rotary-wing aircraft , where the movement of the lift surfaces relative to the air generates lift. A gyroplane is both fixed-wing and rotary wing. Fixed-wing aircraft range from small trainers and recreational aircraft to large airliners and military cargo aircraft. Two things necessary for aircraft are air flow over

6771-521: 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

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6882-596: The cars can be powered, known as a multiple unit . Also, a train can be powered by horses , cables , gravity , pneumatics , and gas turbines . Railed vehicles move with much less friction than rubber tires on paved roads, making trains more energy efficient , though not as efficient as ships. Intercity trains are long-haul services connecting cities; modern high-speed rail is capable of speeds up to 350 km/h (220 mph), but this requires specially built track. Regional and commuter trains feed cities from suburbs and surrounding areas, while intra-urban transport

6993-443: The changing priorities of the urban world. The institution of policy enforces order in transport, which is by nature chaotic as people attempt to travel from one place to another as fast as possible. This policy helps to reduce accidents and save lives. Relocation of travelers and cargo are the most common uses of transport. However, other uses exist, such as the strategic and tactical relocation of armed forces during warfare , or

7104-480: The cheapest mode of transport but are not necessarily flexible, and taxis are very flexible but more expensive. In the middle is demand-responsive transport , offering flexibility whilst remaining affordable. International travel may be restricted for some individuals due to legislation and visa requirements. An ambulance is a vehicle used to transport people from or between places of treatment, and in some instances will also provide out-of-hospital medical care to

7215-413: The city centres and suburbs. The terminals for automobiles are parking lots , while buses and coaches can operate from simple stops. For freight, terminals act as transshipment points, though some cargo is transported directly from the point of production to the point of use. The financing of infrastructure can either be public or private . Transport is often a natural monopoly and a necessity for

7326-481: The civilian mobility construction or emergency equipment. Passenger transport, or travel, is divided into public and private transport . Public transport is scheduled services on fixed routes, while private is vehicles that provide ad hoc services at the riders desire. The latter offers better flexibility, but has lower capacity and a higher environmental impact. Travel may be as part of daily commuting or for business , leisure, or migration . Short-haul transport

7437-551: 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

7548-465: 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

7659-414: The different kinds of transport facilities used to carry people or cargo. They may include vehicles, riding animals , and pack animals . Vehicles may include wagons , automobiles , bicycles , buses , trains , trucks , helicopters , watercraft , spacecraft , and aircraft . A mode of transport is a solution that makes use of a certain type of vehicle, infrastructure, and operation. The transport of

7770-441: 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

7881-554: The flight, allowing it to take off and land vertically, hover, and fly forward, backward, or laterally. Helicopters have several different configurations of one or more main rotors. Helicopters with a single shaft-driven main lift rotor require some sort of antitorque device such as a tail rotor , fantail , or NOTAR , except some rare examples of helicopters using tip jet propulsion, which generates almost no torque. An autogyro (sometimes called gyrocopter, gyroplane, or rotaplane) uses an unpowered rotor, driven by aerodynamic forces in

7992-416: 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

8103-464: 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

8214-404: 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

8325-580: 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

8436-759: The key driving factors in international trade and globalization since the 1950s. Bulk transport is common with cargo that can be handled roughly without deterioration; typical examples are ore , coal, cereals , and petroleum . Because of the uniformity of the product, mechanical handling can allow enormous quantities to be handled quickly and efficiently. The low value of the cargo combined with high volume also means that economies of scale become essential in transport, and gigantic ships and whole trains are commonly used to transport bulk. Liquid products with sufficient volume may also be transported by pipeline. Air freight has become more common for products of high value; while less than one percent of world transport by volume

8547-404: 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

8658-530: 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

8769-609: 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

8880-609: The lift required. Additional fixed wings may also be provided to help with stability and control and to provide auxiliary lift. An early American proposal was the conversion of the Lockheed F-104 Starfighter with a triangular rotor wing. The idea was later revisited by Hughes. The Sikorsky S-72 research aircraft underwent extensive flight testing. In 1986 the Sikorsky S-72 Rotor Systems Research Aircraft (RSRA)

8991-429: The main source of harmful noise and air pollution in cities; buses allow for more efficient travel at the cost of reduced flexibility. Road transport by truck is often the initial and final stage of freight transport. Water transport is movement by means of a watercraft —such as a barge , boat , ship , or sailboat —over a body of water, such as a sea , ocean , lake , canal , or river . The need for buoyancy

9102-431: The movement of people, goods, and services. Land transport plays a vital role in linking communities to each other. Land transport is a key factor in urban planning . It consists of two kinds, rail and road. Rail transport is where a train runs along a set of two parallel steel rails, known as a railway or railroad. The rails are anchored perpendicular to ties (or sleepers) of timber, concrete, or steel, to maintain

9213-405: The nature of the cargo transport, in which mode is chosen. Logistics refers to the entire process of transferring products from producer to consumer, including storage, transport, transshipment, warehousing, material-handling, and packaging, with associated exchange of information. Incoterm deals with the handling of payment and responsibility of risk during transport. Containerization , with

9324-515: 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

9435-477: 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

9546-506: 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 ,

9657-598: The patient. The word is often associated with road-going "emergency ambulances", which form part of emergency medical services , administering emergency care to those with acute medical problems. Air medical services is a comprehensive term covering the use of air transport to move patients to and from healthcare facilities and accident scenes. Personnel provide comprehensive prehospital and emergency and critical care to all types of patients during aeromedical evacuation or rescue operations, aboard helicopters, propeller aircraft, or jet aircraft. Freight transport, or shipping,

9768-418: 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

9879-496: The planets of the Solar System. Suborbital spaceflight is the fastest of the existing and planned transport systems from a place on Earth to a distant "other place" on Earth. Faster transport could be achieved through part of a low Earth orbit or by following that trajectory even faster, using the propulsion of the rocket to steer it. Infrastructure is the fixed installations that allow a vehicle to operate. It consists of

9990-576: 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

10101-431: The profile drag and maintain lift. The effect is a rotorcraft operating in a more efficient manner than the freewheeling rotor of an autogyro in autorotation, minimizing the adverse effects of retreating blade stall of helicopters at higher airspeeds. A rotor kite or gyroglider is an unpowered rotary-wing aircraft. Like an autogyro or helicopter, it relies on lift created by one or more sets of rotors in order to fly. Unlike

10212-399: 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. Rotorcraft A rotary-wing aircraft , rotorwing aircraft or rotorcraft is a heavier-than-air aircraft with rotary wings that spin around

10323-476: The public; roads, and in some countries railways and airports, are funded through taxation . New infrastructure projects can have high costs and are often financed through debt . Many infrastructure owners, therefore, impose usage fees, such as landing fees at airports or toll plazas on roads. Independent of this, authorities may impose taxes on the purchase or use of vehicles. Because of poor forecasting and overestimation of passenger numbers by planners, there

10434-418: 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

10545-494: 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

10656-399: 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

10767-512: 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

10878-473: 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)

10989-404: 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

11100-403: The rotor with additional thrust engines, propellers, or static lifting surfaces. Some types, such as helicopters, are capable of vertical takeoff and landing . An aircraft which uses rotor lift for vertical flight but changes to solely fixed-wing lift in horizontal flight is not a rotorcraft but a convertiplane . A helicopter is a powered rotorcraft with rotors driven by the engine(s) throughout

11211-406: 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

11322-437: The seven wastes (Japanese term: muda ) which do not add value to a product. Transport planning allows for high use and less impact regarding new infrastructure. Using models of transport forecasting , planners are able to predict future transport patterns. On the operative level, logistics allows owners of cargo to plan transport as part of the supply chain . Transport as a field is also studied through transport economics ,

11433-437: 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

11544-463: The standardization of ISO containers on all vehicles and at all ports, has revolutionized international and domestic trade , offering a huge reduction in transshipment costs. Traditionally, all cargo had to be manually loaded and unloaded into the haul of any ship or car; containerization allows for automated handling and transfer between modes, and the standardized sizes allow for gains in economy of scale in vehicle operation. This has been one of

11655-483: 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

11766-958: The total land use. An efficient transport system can reduce land waste. Road 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. 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

11877-514: The transport industry, operations and ownership of infrastructure can be either public or private, depending on the country and mode. Passenger transport may be public , where operators provide scheduled services, or private . Freight transport has become focused on containerization , although bulk transport is used for large volumes of durable items. Transport plays an important part in economic growth and globalization , but most types cause air pollution and use large amounts of land . While it

11988-408: The vehicle from one lane to the other and from one road to another according to the need and convenience. This flexibility of changes in location, direction, speed, and timings of travel is not available to other modes of transport. It is possible to provide door-to-door service only by road transport. Automobiles provide high flexibility with low capacity, but require high energy and area use, and are

12099-655: The vehicle must have a compartment, seat, or platform for the passengers. Simple vehicles, such as automobiles, bicycles, or simple aircraft, may have one of the passengers as a driver. Recently, the progress related to the Fourth Industrial Revolution has brought a lot of new emerging technologies for transportation and automotive fields such as Connected Vehicles and Autonomous Driving. These innovations are said to form future mobility, but concerns remain on safety and cybersecurity, particularly concerning connected and autonomous mobility. Private transport

12210-426: The wings for lift and an area for landing . The majority of aircraft also need an airport with the infrastructure for maintenance, restocking, and refueling and for the loading and unloading of crew, cargo, and passengers. While the vast majority of aircraft land and take off on land, some are capable of take-off and landing on ice, snow, and calm water. The aircraft is the second fastest method of transport, after

12321-480: Was fitted with a four-bladed stopped rotor, known as the X-wing. The programme was cancelled two years later, before the rotor had flown. The later canard rotor/wing (CRW) concept added a "canard" foreplane as well as a conventional tailplane, offloading the rotor wing and providing control during forward flight. For vertical and low-speed flight, the main airfoil is tip-driven as a helicopter's rotor by exhaust from

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