Innovative traffic control practices in Europe.
Vehicular travel is increasing throughout the world, particularly in large urban areas. Accommodating the increased demand, while improving traffic safety, has led transportation officials to use a variety of innovative traffic control practices.
These practices are used to control traffic movement and to provide road users with better information upon which to base travel decisions. By using these practices, transportation professionals can operate the transportation system more efficiently and safely.
In recent years, traffic engineers in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. have implemented a number of practices to improve the overall quality of traffic flow. However, the need for improved traffic control is a worldwide need, and many other countries have also implemented innovative traffic control practices. Recognizing the benefits that could result from an examination of international practices, a team of traffic engineers was formed to observe and document practices that might have value to U.S. practitioners.
This "scan team" effort was jointly sponsored by the Federal Highway Administration The Federal Highway Administration (FHWA) is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," The Federal-aid Highway Program and the Federal Lands Highway (FHWA FHWA Federal Highway Administration (US DoT) ), the American Association American Association refers to one of the following professional baseball leagues:
In May 1998, the team of 10 U.S. traffic engineers traveled to Europe to observe innovative traffic control practices and identify those practices that could be implemented in the United States. The team members represented several different perspectives, including federal, state, and local governments and two research organizations. The team members were Linda L. Brown (FHWA), J. Lynwood Butner (Virginia Department of Transportation The Virginia Department of Transportation (VDOT) is the government agency responsible for building, maintaining and operating Virginia's roads, bridges and tunnels. It is overseen by the Commonwealth Transportation Board, which has the power to fund airports, seaports, rail [DOT]), Richard Cunard (Transportation Research Board), Sterling C. Davis (Utah DOT), Edward L. Fischer (Oregon DOT), H. Gene Hawkins Jr. (Texas Transportation Institute The Texas Transportation Institute (TTI) is the largest transportation research agency in the United States. Created in 1950, primarily in response to the needs of the Texas Highway Department (now the Texas Department of Transportation), TTI has since broadened its focus to ), Mark R. Kehrli (FHWA), Peter F. Rusch (Wisconsin DOT), Samuel C. Tignor (FHWA), and W. Scott Wainwright Wainwright, town (1991 pop. 4,732), E Alta., Canada, SE of Edmonton and near the Sask. border. It is a trade center and railroad division point for an oil and natural gas area. It has oil refineries, grain elevators, and flour mills. Nearby is a military base. (Montgomery County Montgomery County may refer to:
During a two-week period, the team visited with transportation officials in Gothenburg, Sweden; Frankfurt, Cologne, and Bonn, Germany; Paris, France; and London and Birmingham, England. These host officials presented information on a wide variety of traffic engineering and traffic control topics, and the team observed many other interesting practices during the travel between visits.
At the start, midpoint mid·point
1. Mathematics The point of a line segment or curvilinear arc that divides it into two parts of the same length.
2. A position midway between two extremes. , and end of the trip, the team members met to discuss their observations and to identify those practices that might be worthwhile in the United States. The team identified many noteworthy practices, several of which may have current or future value to transportation agencies in the United States.
This article summarizes the findings and recommendations resulting from the scan trip. The information is organized into five major categories:
* Traffic control devices.
* Freeway control.
* Operational practices.
* Information management.
* Administrative practices.
An FHWA report describes the findings, observations, and recommendations of the scan trip in greater detail.
Traffic Control Devices
As the team traveled between and within each country, they had an opportunity to observe various European practices for traffic control devices. Many of these practices are significantly different from the corresponding U.S. practice - if one exists. The two practices that the team members believe would have the greatest potential value in the United States are the tiger-tail marking used on freeway entrance and exit ramps exit ramp n (US) (AUT) → vía de acceso
exit ramp exit n (US) (Aut) → bretelle f d'accès
exit ramp and the all-white system of pavement markings used throughout Europe.
The tiger-tail marking is an innovative pavement marking pattern that is used on multilane mul·ti·lane
Having several lanes: a multilane highway.
Adj. 1. multilane - (of roads and highways) having two or more lanes for traffic freeway entrance and exit ramps in England. The marking separates multiple lanes by using a wide, painted buffer. The buffer separates the merge/diverge points of each lane, reducing turbulence and improving operations as traffic enters or leaves the mainline mainline Drug slang verb To inject a drug .
As the team traveled through Europe, they were very impressed by the quality of the pavement marking systems and by the ability to communicate information to drivers through the use of white markings only. The Europeans use a wide variety of pavement marking patterns (line width, number of lines, line/gap ratio, etc.) to convey the necessary information to road users. They also use significantly more marking material than is commonly used in the United States. The team members feel that the European system of all-white markings could provide some benefits and deserves close examination to determine its potential here.
The team also observed many other European practices related to traffic control devices. These practices include: countdown markers for exit ramps, arrowhead-shaped destination signs, internal sign illumination in urban areas, use of a dotted sign border for trailblazing trail·blaz·ing
Suggestive of one that blazes a trail; setting out in a promising new direction; pioneering or innovative: trailblazing research; a trailblazing new technique. , variations in alphabet stroke width, horizontal signing, chevrons for vehicle spacing, colored pavements, raised crosswalks, flashing yellow on pedestrian clearance, audible pedestrian signals, worker-visibility enhancements, vehicle-visibility enhancements, workzone traffic control, freeway exit signs, and rotary intersections.
Many of the freeways (or motorways as they are known in Europe) in urban areas experience high levels of congestion The condition of a network when there is not enough bandwidth to support the current traffic load.
congestion - When the offered load of a data communication path exceeds the capacity. . Practitioners in all four countries have implemented many different strategies for controlling traffic on these congested con·gest·ed
Affected with or characterized by congestion.
congested ENT adjective Referring to a boggy blood-filled tissue. See Nasal congestion. freeways. The three freeway control practices that the team members feel should be implemented in the United States are variable speed control, lane control signals, and incident and queue detection and protection.
One of the most interesting observations of the trip was the extent to which the host countries use dynamic signs to present variable speed limits to drivers. Operating agencies were able to achieve considerable benefits in traffic flow and safety on freeways by dynamically changing the speed limit based on real-time traffic speed and flow data. The high level of compliance with these signs was attributed to the correlation of the speeds to actual freeway conditions in real time and to the use of cameras and photographs to identify speeders on some freeways.
Lane control signals were also widely used on European freeways - most commonly in conjunction with dynamic message signs and variable speed limits. A signal is mounted above each lane to indicate traffic conditions downstream. These signals use a red X, yellow diagonal down arrow, or green down arrow to indicate that a lane is closed, closed ahead, or open, respectively.
Freeway queue detection and protection were observed in all four countries. Sensors (primarily loops) are placed in freeway mainlanes (and sometimes in the shoulder lanes) to identify when a line of backed-up traffic forms and where the back of the queue is located. The operating agency uses this information to provide advance notice of the presence of a queue. The information presented to drivers may be an advisory speed, a speed limit, or a congestion warning message (symbol or words). Some of the response systems are fully automated. In some locations, another or additional form of queue protection is provided by placing incident response vehicles with flashing lights Flashing Light is a rhythmic light in which the total duration of the light in each period is clearly shorter than the total duration of the darkness and in which the flashes of light are all of equal duration. and/or dynamic message signs on the shoulder at the end of the queue. These vehicles back up as the queue proceeds upstream.
Our European hosts use many unique and interesting operational practices to control traffic. The scan team recommends two practices for possible implementation in the United States: intelligent speed adaption adaption
see adaptation. and self-optimized traffic signal control.
Intelligent speed adaption (ISA (1) (Instruction Set Architecture) See instruction set.
(2) (Interactive Services Association) See Internet Alliance.
(3) (Internet Security and Acceleration) See .NET. ) consists of processes that monitor the current speed of a vehicle and can instigate To incite, stimulate, or induce into action; goad into an unlawful or bad action, such as a crime.
The term instigate is used synonymously with abet, which is the intentional encouragement or aid of another individual in committing a crime. a corrective action A corrective action is a change implemented to address a weakness identified in a management system. Normally corrective actions are instigated in response to a customer complaint, abnormal levels if internal nonconformity, nonconformities identified during an internal audit or if that speed is not appropriate. Sweden has tested a system of intelligent speed adaption in which a "road beacon" transmits a signal to a receiver in the vehicle; the driver is alerted by a sound or light signal if he is exceeding the posted or safe speed.
An automatic ISA system that directly limits the vehicle's speed was also tested in Sweden. The test vehicles were equipped with a device that could be turned on and off by radio signals. When turned on, the speed of the vehicle was limited to 50 kilometers per hour. The driver experienced resistance in the accelerator, and it was not possible to increase speed even if the accelerator was depressed further.
An interesting traffic signal operational practice was presented by the Swedish officials. At isolated intersections, they are testing self-optimized signal control (SOS SOS, code letters of the international distress signal. The signal is expressed in International Morse code as … — — — … (three dots, three dashes, three dots). ) as a means to improve safety. SOS is a sophisticated system of detection and traffic signal controller logic that enables the change in right-of-way between opposing traffic movements to be made based on assessing and minimizing the safety risks for traffic that will be stopped on the approaches. It is a dilemma-zone enhancement that translates stopping risks and cross-street queue development to a cost algorithm.
The team also observed many other European operational practices related to traffic control. These include: use of historical loop data during loop-failure conditions, innovative coordinated signal-preemption strategies, automated speed enforcement, emergency telephones, and elevated police patrol bays. The use of automated enforcement was particularly evident throughout the four countries.
The team members were impressed by the amount of information that European agencies provide to road users. The Europeans have placed a strong emphasis on presenting easy-to-understand information to drivers.
Even though the team members expected to see the extensive use of symbols, they were nonetheless impressed by the extent and success of symbols. Symbols (or pictograms as they are more commonly called in Europe) are widely used in variable message signs. Typical symbols that are presented in these signs include congestion, snow, danger, workers, and slippery pavement.
Symbols in the form of geometric shapes This is a list of geometric shapes. Generally composed of straight line segments
The team learned that dynamic message signs along the freeway are also used to provide drivers with travel-time information. One of the most impressive examples of this practice was found in Paris where more than 200 dynamic message signs on the outer ring freeway, its entrance ramps entrance ramp n (US) (AUT) → rampa de acceso
entrance ramp entrance n (US) (Aut) → bretelle f d'accès
, and the inner ring provide real-time travel times to upcoming junctions. An evaluation of this system in 1994 found that 65 percent of the motorists preferred travel-time information over congestion information.
The team also observed many other European practices related to information management. These practices include: consistency in variable message signs, real-time parking information, traffic information on FM radio, and private-sector collection of traffic data for traveler information.
European transport agencies are actively pursuing partnerships with the private sector to collect traffic data. In several countries, commercial firms are allowed to install, operate, and maintain supplemental traffic detectors to enhance their own for-profit traffic information databases.
[TABULAR DATA FOR TABLE 1 OMITTED]
In addition to the benefits derived from discussing and observing traffic control practices, the team gained valuable insight into the administrative issues associated with operating a transportation system. The team found that European transportation officials place a significant emphasis on "marketing" traffic engineering practices and improvements.
One of the key observations of the team is that when justifying transportation programs to policy-makers and elected officials, several of the countries emphasize safety benefits and improved incident response times by emergency services emergency services Emergency care '…services …necessary to prevent death or serious impairment of health and, because of the danger to life or health, require the use of the most accessible hospital available and equipped to furnish those services' instead of improved operations or congestion reduction. This is particularly true for the heavily congested freeways and highways.
The most prominent examples of the safety emphasis were found in Sweden. The Swedish government has adopted a safety strategy known as "Vision Zero." The objective of this strategy is to eliminate fatalities on Swedish highways.
An example of the emphasis on business practices was found in England where transportation improvements are evaluated using a "Value for Money" concept. Each improvement is carefully assessed with respect to expenditures and expected benefits.
Several of the interesting concepts identified by the team related to the effort to reintegrate re·in·te·grate
tr.v. re·in·te·grat·ed, re·in·te·grat·ing, re·in·te·grates
To restore to a condition of integration or unity.
re telematics Originally coined to mean the convergence of telecommunications and information processing, the term later evolved to refer to automation in automobiles. GPS navigation, integrated hands-free cellphones, wireless communications and automatic driving assistance systems all come under the , intelligent transportation systems, into the existing organizational structure This article has no lead section.
To comply with Wikipedia's lead section guidelines, one should be written. and transportation system. This effort was initiated to ensure that the use of technology is inherent within the traditional organizational components and more readily assimilated within the political, customer, and organizational arenas as a critical component of long-term transportation solutions.
The European emphasis on customer service was best exemplified in a French private-sector toll facility. The high-quality facility demonstrated that standards in construction, operation, and maintenance were actually being exceeded to promote the future acceptance and expansion of these types of facilities.
The team was also very impressed with the administrative commitment to transportation research in several countries and with the safe and efficient management of high-speed freeways.
The members of the scan team were privileged to travel to four European countries to see firsthand first·hand
Received from the original source: firsthand information.
first many outstanding traffic control and traffic engineering practices. Following the meetings with the host countries, the team members met to review the findings from the trip and to identify those practices that have the greatest potential for successful implementation in the United States.
The resulting recommendations are divided into primary recommendations and additional recommendations. The primary recommendations, which have been briefly described in this article, represent the team's recommendations for practices that should receive strong consideration for implementation in the United States. The scan team report provides more detail on the additional recommendations. Table 1 summarizes the team's recommendations.
In some cases, the practices can be implemented with little or no change in current U.S. practices or standards. In other cases, implementation must be preceded by research that addresses U.S. aspects of a topic. The implementation of the recommended traffic control practices will ensure that our citizens receive the maximum benefit of innovative traffic controls to save lives, enhance operational efficiency, and improve the movement of traffic in the United States.
Dr. H. Gene Hawkins Jr., the scan team reporter, is an assistant research engineer and program manager at the Texas Transportation Institute, where he supervises and conducts research with an emphasis on driver communication through traffic control devices and on freeway operations. He earned his bachelor's, master's, and doctoral degrees in civil engineering at Texas A&M University. He is a registered professional engineer in Texas.
W. Scott Wainwright i.s chief of the Division of Traffic and Parking Services in the Montgomery County (Md.) Department of Public Works public works
Construction projects, such as highways or dams, financed by public funds and constructed by a government for the benefit or use of the general public.
Noun 1. and Transportation. He is a Fellow of the Institute of Transportation Engineers Institute of Transportation Engineers (ITE) is an international educational and scientific association of transportation professionals who attempt to meet mobility and safety needs and was founded in 1930. ITE is a standards development organization designated by the U.S. (ITE ITE Institute of Transportation Engineers
ITE In the Ear
ITE Information Technology Equipment
ITE Initial Teacher Education (UK)
ITE Institute of Technical Education
ITE Institute of Terrestrial Ecology ) and a member of the ITE International Board of Direction. He has a bachelor's degree in civil engineering from Virginia Polytechnic Institute and State University Virginia Polytechnic Institute and State University, at Blacksburg; land-grant and state supported; coeducational; chartered and opened 1872 as an agricultural and mechanical college. and a master's degree master's degree
An academic degree conferred by a college or university upon those who complete at least one year of prescribed study beyond the bachelor's degree.
Noun 1. in civil engineering from the University of Connecticut The University of Connecticut is the State of Connecticut's land-grant university. It was founded in 1881 and serves more than 27,000 students on its six campuses, including more than 9,000 graduate students in multiple programs.
UConn's main campus is in Storrs, Connecticut. . He is a licensed professional engineer in Maryland.
Dr. Samuel C. Tignor, the scan team leader, is the chief of the Traffic and Driver Information Systems Division, Office of Safety Research and Development, Federal Highway Administration. He manages research pertaining per·tain
intr.v. per·tained, per·tain·ing, per·tains
1. To have reference; relate: evidence that pertains to the accident.
2. to traffic signs, markings, and signals; lighting; work-zone safety; railroad-highway grade crossings; speed control; and human factors. He has a bachelor's degree in civil engineering from Virginia Polytechnic Institute and State University and a master's degree and doctorate in civil engineering from the University of Michigan (body, education) University of Michigan - A large cosmopolitan university in the Midwest USA. Over 50000 students are enrolled at the University of Michigan's three campuses. The students come from 50 states and over 100 foreign countries. . He is a professional lecturer in engineering at The George Washington University George Washington University, at Washington, D.C.; coeducational; chartered 1821 as Columbian College (one of the first nonsectarian colleges), opened 1822, became a university in 1873, renamed 1904. , and he is a registered professional engineer in the District of Columbia District of Columbia, federal district (2000 pop. 572,059, a 5.7% decrease in population since the 1990 census), 69 sq mi (179 sq km), on the east bank of the Potomac River, coextensive with the city of Washington, D.C. (the capital of the United States). .