Introduction to Traffic Engineering
Course Outline Total credit hours = 40 Credit = 2.5 Teaching approach = English with Chinese explanation Text book = Traffic Engineering Course Characteristics --- compulsory Final score --- based on final exam, homework and attendance
Objectives of course Help students lay solid foundation of traffic engineering as a whole Help students get general knowledge of traffic engineering from both theory and practice Lead students to traffic/transportation professional world
Chapter 1. Introduction Definition, scope and goal Objects of traffic engineering Background of traffic engineering development Some basic concepts in traffic engineering Main elements in traffic engineering Characteristics Challenges traffic engineers face References
1. Definition, scope and goal Definition of Traffic Engineering --- It is the phase of transportation engineering that deals with the planning, geometric design and traffic operations of roads, streets and highways, their networks, terminals, abutting lands, and relationships with other modes of transportation
Transportation Engineering is defined as a discipline applying technology and scientific principles to the planning, functional design, operation, and management of facilities for all modes of transportation Transportation mode includes: land, rail, water,air and pipe (refer to Table 1.1 on page 8-9) The focus of this course is on surface (land) transportation and connection with other modes
Scope of Traffic Engineering --- surface (land)transportation; relationships and connection with other modes of transportation Major modes of surface transportation --- automobile, bus, truck and bike
Goal of Traffic Engineering --- explore how to provide for the safe, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods. Safe --- public safety Rapid --- time value and customer service Comfortable/convenient --- level of service Economical --- social cost Environmental --- clean air and sustainability Movement = mobility
2. Objects of traffic engineering Roadways --- main object to search for Vehicles --- some of them Drivers --- key element but difficult to study Biker & Pedestrians --- education Environment --- still remain in concept and difficult to exercise in practice
3. Background of development Automobile industry Urbanization Computer and ITS (Intelligent Transportation System Environmentalism (green transportation system and sustainable development concept
4.5 4 3.5 3 million 系列 1 trend 1 系列 2 trend 2 系列 3 trend 3 4.2 3.8 3.2 2.5 2 2.124 1.5 1 0.5 0 1987 1991 1995 1999 2003 2007 2010 Trend forecast for auto development in Beijing
Development of traffic engineering in China Open undergraduate program in 1980 at Beijing University of Technology About 90 colleges and universities in mainland to offer traffic engineering courses Status of transportation in urban planning process has seen great improvement High investments in highway and traffic engineering studies
4. Basic Concepts in Traffic Engineering Mobility versus Accessibility Highway Classification Uninterrupted and Interrupted flows Responsibility and Liability Transportation Legislation
Mobility versus Accessibility Mobility refers to the ability to travel to many different destinations, while accessibility refers to the ability to gain entry to a particular site or area With an increase of mobility the ability to access development decreases, and vise versa.
P R O P O R T IO N O F S E R V IC E M o b ility F re e w a y A rte ria ls (M a jo r R o a d ) C o lle c to rs (M in o r R o a d ) L a n d A c c e s s L o cals(t ertiary S treet) F ig u re 1.1 R ela tio n sh ip o f fu n ctio n a lly cla ssified sy stem in serv ice tra ffic m o b ility a n d la n d
Graphic description between mobility and accessibility
Highway classification Location -- urban and suburban (rural) Criterion --- specification for roadway design Each country has different way in determining hierarchy of highways The purpose of conducting classification for highway is to clarify the functionality of each category of roadways in providing services in terms of mobility and accessibility
China United States Urban Rural Urban Rural Freeway Freeway Freeway Interstate Expressway 1st Class Highway Major Street 2nd Class Highway Arterials Primary Minor Street 3rd Class Highway Collector Secondary Tertiary Street 4th Class Highway Local Street Tertiary With increase of mobility the accessibility will decrease Freeway has the highest mobility; whereas local street has the highest accessibility
Freeways or expressways --- access-controlled, multilane, divided highways devoted to high-speed, long-distance travel with little or no access adjacent to land Arterials --- roadways serving primarily to move traffic between principal traffic generators with partially access-controlled (residential access is discouraged, but commercial access is allowed), there are two categories: major and minor
Collectors --- roadways serving internal traffic movements within an urban area and connecting it with the arterial system, there are two categories: major and minor Local streets --- primarily providing access to the development with low-speed
S. AFRICA GENERAL CLASSIFICATION Primary Class Likely Features Most Likely Generic Function No Authorities Description Long distance 1. between cities, provinces or countries National Freeways, trunk roads Vehicle Priority (mobility) 2. Relatively long distance between towns and cities Provincial Expressways, urban motorways, primary arteries 3. Medium distance between districts, municipalities Metropolitan Arterial roads, secondary arteries Mixed Traffic 4. Short distance within districts/suburbs Local/Municipal Collector roads (access) 5. Very short distance (500 m max) Local/Municipal Local streets Pedestrian priority 6. Suitable for walking, mobility impaired persons and cyclists Local/Municipal Footpaths/cycleways/ sidewalks, parking lots, woonerwen
Uninterrupted and Interrupted flows Uninterrupted flow facilities have no external interruptions to the traffic stream. Pure uninterrupted flow exists mainly on freeways and expressways. Interrupted flow facilities have external interruptions to the traffic stream. Almost all urban surface streets and highways are interrupted flow facilities.
Uninterrupted flow facilities are fully or partially accesscontrolled Freeway in Germany (2008) Expressway in Beijing (2007)
Interrupted flow facilities are not access-controlled, with external disruptions, resulting in stop-and-go Urban street in Atlantic City, USA Urban street in Beijing
Responsibility and Liability Public safety Legal obligation --- legal case Communication with people traffic engineers work for --- public hearing public involvement Community protection --- traffic calming
Lane reduction is one of traffic calming strategies Leeds, England Dresden, Germany
Transportation Legislation of USA Federal-Aid Highway Act (1916 to 1983) Intermodal Surface Transportation Efficiency Act (ISTEA) from 1991 to 1997 Transportation Equity Act for the 21st Century (TEA-21) from 1998 to 2004 SAFETEA-LU (Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users 2005 to 2011)
5. Main Elements in Traffic Engineering Traffic studies --- data collection and reduction Performance evaluation --- set of criteria to measure the quality of traffic performance Facility design --- functional and geometric designs Traffic control --- establishment of traffic regulation and their communication to the driver through signs, markings, and signals
Traffic operations --- traffic organization, transit operation, TSM --- Transportation Systems Management ITS --- Intelligent Transportation Systems
6. Characteristics The discipline is still quite young as compared to other disciplines. Thus, there leave rooms for improvement. The coverage is so broad that it is difficult to identify the boundary of the discipline. The discipline is closely associated with the daily life of the public (fishbowl effect)
7. Challenges Traffic Engineers Face Change in notion from increasing capacity to meet demand to managing the movement of vehicle and people Ever-increasing congestion Safety and security of transportation facilities Technologically sound solutions may not be socially acceptable (staggering of work time; public transit)
Congestion on Roadway of Beijing
Evacuation before hurricane in Houston, USA, 2005 9.11 event in 2001, USA
Traffic paralysis due to snow storm in southern China 2008
8. References ITE --- Institute of Transportation Engineers TRB --- Transportation Research Board ASCE --- American Society of Civil Engineers MUTCD --- Manual on Uniform Traffic Control Devices HCM 2000--- Highway Capacity Manual AASHTO Green Book --- American Association of State Highway and Transportation Officials named a book titled A Police on the Geometric Design of Highway and Street The Traffic Engineering Handbook Trip Generation Handbook 2000 Access Management Manual 2003
Technical terms Traffic (highway) engineering --- automobile, engineering-oriented Transportation engineering --- all modes, social, legal, political-oriented, Transport engineering --- British usage having same meaning of transportation; used as a verb Communication --- Conveyance --- means of transport
5E-featured discipline Enforcement Education Engineering Environment Energy
Be aware of Traffic engineering is still young as compared to other discipline, therefore, there leaves much to be desired Traffic problems can t be purely resolved by applying traffic engineering knowledge Approaches learned from other countries do not necessarily applicable for our situation Engineering judgment plays key role