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Trucking industry in the United States

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发表于 2008-11-7 23:22:50 | 显示全部楼层 |阅读模式
http://en.wikipedia.org/wiki/Trucking_industry_in_the_United_States

Trucking industry in the United StatesFrom Wikipedia, the free encyclopedia
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A common property-carrying commercial vehicle in the United States is the semi-truck, also known as an "18-wheeler".


The trucking industry (also referred to as the transportation or logistics industry) is the transport and distribution of commercial and industrial goods using commercial motor vehicles (CMV). In this case, CMVs are most often trucks; usually a semi truck, box truck, or dump truck. A truck driver (commonly referred to as a "trucker") is a person who earns a living as the driver of a CMV.
The trucking industry provides an essential service to the American economy by transporting large quantities of raw materials, works in process, and finished goods over land—typically from manufacturing plants to retail distribution centers. Trucks are also important to the construction industry, as dump trucks and portable concrete mixers are necessary to move the large amounts of rocks, dirt, concrete, and other building materials used in construction. Trucks in America are responsible for the majority of freight movement over land, and are vital tools in the manufacturing, transportation, and warehousing industries.
Large trucks and buses require a commercial driver's license (CDL) to operate. Obtaining a CDL requires extra education and training dealing with the special knowledge requirements and handling characteristics of such a large vehicle. Drivers of CMVs must adhere to the hours of service, which are regulations governing the driving hours of commercial drivers. These, and almost all other rules regarding the safety of interstate commercial driving, are issued by the Federal Motor Carrier Safety Administration (FMCSA). The FMCSA is also a division of the United States Department of Transportation, which governs all transportation-related industries such as trucking, shipping, railroads, and airlines.
Recent developments in technology, such as computers, satellite communication, and the internet, have contributed to many improvements within the industry. These developments have increased the productivity of company operations, saved the time and effort of drivers, and provided new, more accessible forms of entertainment to men and women who often spend long periods of time away from home. The U.S. Environmental Protection Agency has recently implemented revised emission standards for diesel trucks (reducing airborne pollutants emitted by diesel engines) which promises to improve air quality and public health.
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[edit] HistoryBefore 1900, most freight transported over land was carried by trains using railroads. Trains were highly efficient at moving large amounts of freight, but could only deliver that freight to centralized urban centers for distribution by horse-drawn transport. The few trucks that existed at the time were mostly novelties, appreciated more for their advertising space than for their utility. The use of range-limited electric engines, lack of paved rural roads, and small load capacities limited trucks to mostly short-haul urban routes.[1]
Starting in 1910, the development of a number of technologies would give rise to the modern trucking industry. With the advent of the gasoline-powered internal combustion engine, improvements in transmissions, the move away from chain drives to gear drives, and the development of the tractor/semi-trailer combination, shipping by truck was gaining in popularity.[1] In 1913, the first state weight limits for trucks were introduced. Only four states were limiting truck weights, from a low of 18,000 pounds (8,200 kg) in Maine to a high of 28,000 pounds (13,000 kg) in Massachusetts. These laws were enacted to protect the earth and gravel-surfaced roads from damage caused by the iron and solid rubber wheels of early trucks.[2] By 1914 there were almost 100,000 trucks on America's roads. However, solid tires, poor rural roads, and a maximum speed of 15 miles per hour (24 km/h) continued to limit the use of these trucks to mainly urban areas.[1]

World War I trucks circa 1917, manufactured by White Motor Company



The years of World War I (1914-1918) spurred rising truck use and development, as the increased congestion of railroads during the busy war years exposed the need for alternative modes of transporting cargo.[3] It was during these years when Roy Chapin (working with a military committee) began to experiment with the first long-distance truck shipments, and pneumatic (inflated) tires capable of supporting heavier loads were developed which enabled trucks to drive at higher speeds.[1] Two truck manufacturers that emerged during this time were a former sewing machine maker, White (pictured above), and one that would become a modern euphemism for "truck," Mack.[4] By 1920 there were over a million trucks on America's roads.[1]
[url=http://en.wikipedia.org/wiki/Imageine3174_-_Shipping_Containers_at_the_terminal_at_Port_Elizabeth,_New_Jersey_-_NOAA.jpg][/url] [url=http://en.wikipedia.org/wiki/Imageine3174_-_Shipping_Containers_at_the_terminal_at_Port_Elizabeth,_New_Jersey_-_NOAA.jpg][/url]
Intermodal containers waiting to be transferred between ships, trains, and trucks are stacked in holding areas at a shipping port.


The years beyond 1920 saw a number of advancements, such as improved rural roads, the introduction of the diesel engine (which are more efficient than gasoline engines), the standardization of truck and trailer sizes along with fifth wheel coupling systems, as well as power assisted brakes and steering.[1] By 1933, all states had some form of varying truck weight regulation.[2] Based on recommendations given by the now-abolished Interstate Commerce Commission (ICC), Congress enacted the first hours of service regulations in 1938, limiting the driving hours of truck and bus drivers.[5] In 1941, the ICC reported that inconsistent weight limitations imposed by the states were a hindrance to effective interstate truck commerce.[2]
Also in 1941, President Franklin D. Roosevelt appointed a special committee to explore the idea of a "national inter-regional highway" system, but the committee's progress was halted by the initiation of World War II. After the war was over, the Federal-Aid Highway Act of 1944 authorized the designation of what were now termed "Interstate Highways", but did not include a funding program to build the highways.[3] Limited progress was made until President Dwight D. Eisenhower renewed interest in the plan in 1954. Which began a long, bitter debate between various interests such as rail, truck, tire, oil, and farm groups, over who would pay for the new highways and how.[3]
After compromises had been made, the Federal-Aid Highway Act of 1956 authorized the construction of the Interstate Highway System, an interconnected network of controlled-access freeways which allowed larger trucks to travel at higher speeds through rural and urban areas. This act also authorized the first federal maximum gross vehicle weight limits for trucks, set at 73,208 pounds (33,207 kg).[2] In that same year, modern containerized intermodal shipping was pioneered by Malcom McLean, allowing for more efficient transfer of cargo between trucks, trains, and ships.[6] In the late 1950s, the American Association of State Highway and Transportation Officials (AASHTO) conducted a series of extensive field tests of roads and bridges to determine how traffic contributed to the deterioration of pavement materials. These tests led to a 1964 recommendation by the AASHTO (to Congress) that the gross weight limit for trucks should be determined by a bridge formula table based on axle lengths, instead of a static upper limit.[2] By 1970 there were over 18 million trucks on America's roads.[1]
The Federal-Aid Highway Act Amendments of 1974 established a federal maximum gross vehicle weight of 80,000 pounds (36,000 kg), and introduced a sliding scale of truck weight-to-length ratios based on the bridge formula, but did not establish a federal minimum weight limit. Consequently, six contiguous states in the Mississippi Valley (which came to be known as the “barrier states”) refused to increase their Interstate weight limits to 80,000 pounds, and the trucking industry effectively faced a barrier to efficient cross-country interstate commerce.[2]
The decade of the 70s saw the heyday of truck driving, and the dramatic rise in the popularity of "trucker culture". Truck drivers were romanticized as modern-day cowboys and outlaws[7] (and this stereotype persists even today).[8] This was due in part to their use of Citizens Band (CB) radio to relay information to each other regarding the locations of police officers and transportation authorities. Plaid shirts, trucker hats, CB radios, and using CB slang were popular not just with drivers but among the general public. In 1976, the number one hit on the Billboard chart was "Convoy," a novelty song about a convoy of truck drivers evading speed traps and toll booths across America. The year 1977 saw the release of Smokey and the Bandit, which was the second highest grossing film from that year, beaten only by Star Wars Episode IV.[9] During that same year, CB Bears saw its debut; a Saturday morning cartoon featuring mystery-solving bears who communicate by CB radio. By the start of the 80s the trucking phenomenon had waned, and with the rise of cellular phone technology, the CB radio was no longer popular with passenger vehicles (although truck drivers still use it today).[10]
The Motor Carrier Act of 1980 deregulated the trucking industry, dramatically increasing the number of trucking companies in operation.[11] The trucking workforce was drastically de-unionized, resulting in lower overall pay for drivers.[12] Trucking had lost its spotlight in popular culture, and had become less intimate among drivers due to the increase of both motor carriers and truck drivers. The Surface Transportation Assistance Act of 1982 established a federal minimum for truck weight limits, which finally standardized truck size and weight limits across the country for traffic on the Interstate Highways.[2] By 2006 there were over 26 million trucks on America's roads, hauling over 10 billion tons of freight, and representing nearly 70% of the total volume of freight.[13]
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[edit] Recent yearsAdvances in modern technology have made significant contributions to improvements within the trucking industry. Trucks equipped with numerous satellite communication features and automatic transmissions are not unheard of,[14] and truck stops featuring WiFi internet access are now commonplace.[15]
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[edit] The internetLike many other industries, the trucking industry has benefited from the use of computers and the internet. The internet helps firms explore new opportunities by aggressive sales and marketing. The incremental cost of conducting business transactions on the internet is as much as fifteen times less expensive than paper transactions.[16]
Given the limitations on truck weight and size, increased productivity in the industry comes from two sources; fewer empty miles and less time waiting between loads. Traditional freight brokers acted as intermediaries to manage the coordination of freight, helping independent drivers or companies match loads with available empty trucks. Increasingly, computerized brokers are threatening the future of traditional human brokers by offering increased efficiency. In addition, shipper-driven brokerage over the internet enables shippers to post loads and solicit bids directly from carriers. Instead of relying upon traditional freight brokers, shippers function as their own brokers, dealing directly with freight companies.[16]
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[edit] Exhaust emissions
The Interstate Highway system (2007)



Estimated average annual daily truck traffic for Interstate and major US Highways (1998)


Components of diesel exhaust were confirmed as an animal carcinogen in 1988 by the National Institute for Occupational Safety and Health, and by 2002, the U.S. Environmental Protection Agency (EPA) considered it "likely to be carcinogenic to humans".[17] The particulate matter of diesel exhaust has been linked to (among other health effects) lung cancer, chronic bronchitis, and aggravated asthma; it has also been identified as a greenhouse gas, thus contributing to global warming.[18] For these and other reasons, alternatives and improvements to standard diesel fuel have been developed.
Biodiesel (in its pure form) is a non-toxic, biodegradable form of diesel fuel made from vegetable oil, usually soybean oil or recycled restaurant grease. Biodiesel promises a reduction in some exhaust emissions,[19] as well as reduced dependence on foreign petroleum supplies.[20]
Starting in June 2006, petroleum refiners were required by the EPA to begin producing ultra-low sulfur diesel (ULSD) fuel, which has 97% less sulfur than the previous low sulfur diesel fuel.[21] When fuel containing sulfur is burned, sulfur dioxide is produced, a main component of acid rain.[22] ULSD, together with new air pollution control technologies required in trucks (starting with model year 2007), will reduce harmful emissions by 90%.[21]
By the time the action is fully implemented, the EPA estimates that 2.6 million tons of smog-causing nitrogen oxide emissions will be reduced each year. Soot or particulate matter will be reduced by an estimated 110,000 tons a year. The reduction in sulfur will also prevent an estimated 8,300 premature deaths, 5,500 cases of chronic bronchitis and 17,600 cases of acute bronchitis in children. In addition, an estimated 360,000 asthma attacks and 386,000 cases of respiratory symptoms in asthmatic children will also be avoided every year. [23]
When not driving, truck drivers need to idle their engines to maintain climate control within the truck cab (interior), as well as provide electricity for appliances. Engine idling is inefficient and only adds to the problem of air pollution.[24] This unnecessary idling can be remedied with shore power (which is a term and idea borrowed from the shipping industry), or Truck Stop Electrification.[25] When ships are docked in a port, they connect to a land-based power supply to provide electricity and eliminate the need to idle their engines. The idea of shore power was transferred to the trucking industry, and now there are companies such as IdleAire[26] and Shorepower[27] who provide electricity to diesel trucks, which eliminates the need for the driver to idle the engine. IdleAire also provides access to the internet, cable television, and land line phone services.

[edit] Satellite communicationRecent developments in satellite technology have fostered increased communication and productivity within the trucking industry.[28] This allows a driver to input the information from a bill of lading into a simple text-only dot matrix display screen (commonly called a "Qualcomm", for their ubiquitous OmniTRACS system),[29][30] which allows the driver to communicate with their dispatcher, who is normally responsible for determining and informing the driver of their pick-up and drop-off locations. Drivers are no longer required to find the nearest public phone in order to relay information regarding their load status; it can be done quickly without ever having to leave the truck cab.[28]
The driver inputs the information, using a keyboard, into an automated system of pre-formatted messages known as macros. There are macros for each stage of the loading and unloading process, such as "loaded and leaving shipper" and "arrived at final destination". This system also allows the company to track the drivers fuel usage, speed, gear optimization, engine idle time, location, direction of travel, and amount of time spent driving.[28]
Trucks equipped with GPS satellite navigation units have enabled drivers to forgo a traditional paper-based map, saving time and effort.[15] On the entertainment end, drivers who are willing to pay for satellite radio (or work for a company who pays for it)[31] can listen to commercial-free music, sport, news, and talk radio coast-to-coast without interruptions of signals between cities (as terrestrial radio signals are limited to a certain radius from the broadcasting tower). Thanks to digital satellite television, smaller dish sizes mean truck drivers are not limited to free terrestrial broadcast television, and have more options as to what they watch during their off duty periods.[32]
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[edit] Economic impact
Commercial Freight Activity in the US by Mode of Transportation
Transportation modeModal estimates in millionsRelative shares in percents
ValueTonsValueTons
Truck$9,075,00011,71269.560.1
Rail$392,0001,9793.010.2
Water$673,0001,6685.28.6
Pipeline$896,0003,5296.918.1
Other modes (incl. air, intermodal)$2,015,00060015.43.0
Total$13,052,00019,847100.0100.0
Source: 2002 estimate by the Bureau of Transportation Statistics[33]
The importance of trucking is communicated by the industry adage, "If you bought it, a truck brought it."[15][34] Retail stores, hospitals, gas stations, garbage disposal, construction sites, banks, and even a clean water supply depends entirely upon trucks to distribute vital cargo.[35] Even before a product reaches store shelves, the raw materials and other stages of production materials that go into manufacturing any given product are moved by trucks.[16]
In modern times, railroads are primarily used to haul bulk quantities of cargo over long distances.[36] Unless a manufacturing or distribution facility has a direct connection to the railroad, the remainder of the trip must be handled by truck.[15] Recent implementation of "just in time" strategies have resulted in the increased usage of trucks to help satisfy businesses' fluid inventory needs. Using this strategy, businesses gain the ability to reduce the costs associated with excess inventory and larger warehousing facilities by requiring more frequent deliveries.[37][38][39] According to an industry group, many retail, commercial, and government services require daily or weekly deliveries to keep supplies or merchandise on hand. Many hospitals have also moved to "just in time" inventory systems. The nation's busiest gas stations require deliveries of fuel several times per day, while the average station receives fuel every two to three days. Grocery stores require deliveries of perishable food items every two to three days.[35]
Trucks are vitally important to U.S. industry, however, measuring the impact of trucking on the economy is more difficult, because trucking services are so intertwined with all sectors of the economy. According to the measurable share of the economy that trucking represents, the industry directly contributes about 5% to the gross domestic product annually. In addition, the industry plays a critical support role for other transportation modes and for other sectors of the economy such as the resource, manufacturing, construction, and wholesale and retail trade industries.[16]
Over 80% of all communities in the US rely exclusively on trucks to deliver all of their fuel, clothing, medicine, and other consumer goods. The trucking industry employs 10 million people (out of a total national population of 300 million)[40] in jobs that relate directly to trucking. The trucking industry is the industry of small business, considering 93% of interstate motor carriers (over 500,000) operate 20 or fewer trucks.[41]
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[edit] Truck driversSee also: Truck driver
Shares of the truck driver workforce by age (2004-2014)



Shares of the truck driver workforce by demographic groups (2004-2014)


Truck drivers are persons employed as the operator of a CMV. CMVs can be of varying shapes and sizes, from 10,000-pound (4,500 kg) pickup trucks assigned to haul specialized or small quantities of freight, to 20,000-pound (9,100 kg) straight trucks (box trucks), all the way up to 80,000-pound (36,000 kg), 60-foot (18 m) long 18-wheelers. Trucks are assigned a class rating based upon the gross vehicle weight rating (GVWR). The facts in this section refer to drivers of "heavy duty" trucks (with a GVWR of at least 26,000 pounds (12,000 kg), which require a commercial driver's license to operate).[42]
Truck drivers spend up to 11 hours a day driving, and up to 14 hours a day engaged in various duties (including driving time) such as fueling, filling out paperwork, obtaining vehicle repairs and conducting mandatory vehicle inspections. Long-haul drivers often spend weeks away from home, spending their time off and sleeping at truck stops or rest areas. Driving is relatively dangerous work, as truck drivers account for 12% and the highest total number of all work-related deaths, and are five times more likely to die on the job than the average worker.[43] Smoking, lack of exercise, unhealthy eating habits, and work-related injuries also contribute to the driver's generally risk-prone lifestyle.[44] One survey found 67% of long-haul drivers were smokers or had quit smoking.[45]
In 2006, the U.S. trucking industry employed 1.8 million drivers of heavy trucks.[46] A major problem for the long-haul trucking industry, is that a large percentage of these drivers are aging, and are expected to retire. Very few new hires are expected in the near future, resulting in a driver shortage. As of 2005, within the long-haul sector, there is an estimated shortage of 20,000 drivers. That shortage is expected to increase to 111,000 by 2014.[47] The trucking industry (especially the long-haul sector) is also facing an image crisis due to the long working hours, long periods of time away from home, the dangerous nature of the work, and the relatively low pay (compared to other forms of unskilled labor).[47]
Employee turnover within the long-haul trucking industry is notorious for being extremely high. In the 4th quarter of 2005, turnover within the largest carriers in the industry reached a record 136%,[48] which means for every 100 new employees hired, 136 quit their jobs. This has resulted in a "revolving door" within most long-haul trucking companies, as drivers are constantly switching jobs or quitting the industry altogether. Driver turnover within the short-haul and LTL industries is considerably less (around 15%),[49] mainly due to the better working conditions, higher pay, and unionized workers. One study suggests that larger companies with irregular routes, longer average lengths of hauls, and older equipment experience much higher rates of driver turnover.[49]
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[edit] Rules and regulationsA division of the U.S. Department of Transportation, the Federal Motor Carrier Safety Administration (FMCSA) regulates nearly all aspects of the trucking industry.[50] Truck drivers are limited by the number of daily and weekly hours they may drive, the roads and highways they may drive upon, as well as having a lower legal definition of drunkenness. The Federal Highway Administration has established 0.04% as the blood alcohol concentration (BAC) level at or above which a CMV driver is deemed to be driving under the influence of alcohol.[51] States maintain a BAC level between 0.08% and 0.10% for non-CMV drivers. In some states, trucks also have special speed limits, in addition to restrictions on driving in certain lanes (normally the far left lanes of multi-lane highways).[52]
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[edit] Commercial driver's licenseMain article: Commercial driver's license
Trucks come in many different sizes, creating the need for a truck classification system. Truck drivers are required to have a commercial driver's license (CDL) to operate a CMV carrying more than 16 passengers, carrying a certain amount of hazardous materials, or weighing in excess of 26,000 pounds (12,000 kg).[42] Acquiring a CDL requires a skills test (driving test), and knowledge test (written test) covering the unique handling qualities of driving a large, heavily loaded 18-wheeler, and the mechanical systems required to operate such a vehicle (such as air brakes, vehicle inspection, and backing maneuvers).[53]
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[edit] Hours of serviceMain article: Hours of service

Drivers are required to keep track of driving hours in a log book, using a time grid for each day along with information identifying the vehicle, driver, and company.


The FMCSA defines a CMV as a single or combination (truck and trailer) vehicle with a gross weight of 10,001 pounds (4,536 kg) or more, or is used to transport hazardous materials in quantities requiring the vehicle to be marked or placarded under the hazardous materials regulations.[54] The length of time a driver may spend operating a CMV is limited by a set of rules known as the hours of service (HOS). These laws are designed to protect the general motoring public by reducing accidents caused by driver fatigue. The first version of the HOS were enacted in 1938,[55] and few subsequent revisions have been made since then.[55] The more recent revisions have relied on research into the human circadian rhythm (the tendency for humans to follow a natural 24 hour cycle with 8 hours of uninterrupted sleep).[55] A driver is limited to 11 hours of actual driving within a 14 hour period, after which he/she must rest for 10 hours.[56] The rules do no explicitly require that a driver must sleep, only that a driver must take a period of "rest" within the sleeper berth or off duty (i.e., at home).
Keeping track of a driver's HOS requires the use of a log book.[57] A truck driver's log book is a legally defined form containing a grid outlining the 24 hour day into 15 minute increments. The driver must specify where and when he/she stopped between driving shifts, what duties were performed (if any), along with the driver's name, truck number, company info, and other information. The driver must also present their log book to authorities upon request, for inspection. In lieu of a log book, a motor carrier may substitute an electronic on-board recorder to record the driver's hours.[58]
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[edit] Weight, size, and route restrictionsSee also: Federal Bridge Gross Weight Formula The FMCSA regulates the length, width, and weight limits of CMVs for interstate commercial traffic. Interstate commercial traffic is generally limited a network of interstate freeways and state highways known as the National Network (NN). Provided the truck remains on the NN, they are not subject to the state limits. State limits (which can be lower or higher than federal limits) come into effect for intrastate commercial traffic, provided the vehicle is not on the NN.[59]
There is no federal height limit, and states may set their own limits which range from 13 feet 6 inches (4.1 m) (mostly on the east coast) to 14 feet (4.3 m) (west coast).,[59] As a result, the majority of trucks are somewhere between 13 feet 6 inches and 14 feet high. Truck drivers are responsible for checking bridge height clearances (usually indicated by a warning sign) before passing underneath an overpass or entering a tunnel. Not having enough vertical clearance can result in a "top out" or "bridge hit," causing considerable traffic delays and costly repairs for the bridge or tunnel involved.[60][61]
The federal gross weight limit for a Class 8 truck is 80,000 pounds (36,000 kg) (combined weight of truck, trailer, and cargo).[62] Truck drivers are responsible for checking their own vehicle's weight, usually by paying to be weighed at a truck stop scale. CMVs are subject to various state and federal laws regarding limitations on truck length (measured from bumper to bumper), and truck axle length (measured from axle to axle, or fifth wheel kingpin to axle for trailers). The relationship between axle weight and spacing, known as the Federal Bridge Gross Weight Formula, is designed to protect bridges.[63] Truck weights and sizes are checked by state authorities at a weigh station.

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