INTRODUCTION TO THANSPORTATION

ENGINEERING

CH 1

TRANSPORTATION ENGINEERING

INTRODUCTION

CHAPTER OUTLINE

1.1 Transportation and Transportation Engineering

1.2 Transportation Engineering

1.3 Transportation System

KEY TERMS

transportation engineering [ 交通工程 ] ： the application of scientific principles to the planning, design, operation, and management of transportation systems.

transportation planning [ 交通计划 ] ： an act of laying out a transportation system aiming to predict the needs/demands for a particular service.

ITS( intelligent transportation systems )[ 智能交通系统 ] ： a system providing the opportunity to integrate travelers, vehicles and infrastructure into a comprehensive system through a range of technologies.

IMS-Incident Management Systems [ 事故管理系统 ]: to reduce the effects of incident-related congestion by decreasing the time to detect incidents, the time for responding vehicles to arrive, and the time required for traffic to return to normal conditions, which makes use of a variety of surveillance technologies, often shared with freeway and arterial management systems, as well as enhanced communications and other technologies that facilitate coordinated response to incidents.

SPECIAL WORDS

mph: miles per hour [ 速度单位：英里 / 小时 ]MOEs: measures of effectiveness [ 效力度量 ]MOCs: measures of costs [ 成本度量 ]railroad System Engineering [ 铁路系统工程 ]civil Engineering [ 土木工程 ]structural engineering [ 结构工程 ]traffic signal [ 交通信号 ] pipeline [ 管道 ]highway [ 公路 ]

freeway [ 高速公路 ]beltway [ 环形公路 ]sea-lane [ 航路 ]ubiquity [ 普遍性、通达性 ]mobility [ 机动性 ]geometric design [ 几何设计 ]traffic congestion [ 交通拥堵 ]transportation facility [ 交通设施 ]transportation demand [ 交通需求 ]

1.1 Transportation and Transportation Engineering

Definitions of Transportation

Transportation is everything involved in moving either the person or goods from the origin to the destination.

Consider the businessman’s trip depicted in Figure 1.1.

Hotel

Destination

Home Origin

Transit or Taxi

Automobile

Stop

Walking

WalkingBus StopBus to Hotel

Airport Departure

Airplane

Airport Arrival

Figure 1.1 A businessman’s trip

Transportation engineering is the application of the principles of engineering, planning, analysis, and design to the disciplines comprising transportation: its vehicles, its physical infrastructure, safety in travel, environmental impacts, and energy usage.

It involves “hard” physical sciences and “soft” sciences

What Is Transportation Engineering?

“hard” :the engineer evaluates pavements, geometric design, vehicle design, environmental effects,

and the like.

Transportation Engineering

“soft” :behavior, welfare economics, urban

planning, and political science.

Transportation engineering involves working with the public, with industry, with citizens’ groups, with elected officials, and with employees of the agencies of local, state, and federal governments.

As commonly used, however, the term transportation engineering refers to a subspecialty of civil engineering.

Any such course needs to serve at least three purposes:

1

to provide general information about the practice of transportation engineering for readers, mostly students, who will practice other civil engineering specialties

2

to prepare students who will practice in transportation related jobs immediately upon graduation

3

to provide the necessary background for students who wish to pursue graduate studies in transportation engineering

Transportation and People’s Life

Good transportation provides for the safe, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods.

Everybody is involved with transportation in so great a variety of ways that a mere listing of these ways would take us by surprise.

Progress in Transportation

(1) Historical Development of Transportation

The principles of transportation engineering have been evolving over many millennia.

Human beings are known to have laid out and used convenient routes as early as 30,000 B.C.

Vehicles (and pseudo vehicles) have been in use since human beings learned to walk.

The entire picture for transportation changed in 1885 with Daimler and Benz’s introduction of the gasoline-powered internal-combustion engine.

Some of the most outstanding technological developments in transportation have occurred in the preceding 200 years:

The first pipelines in the United States were introduced in 1861.

First railroad opened in 1825. The internal-combustion engine was invented in 1866 The first automobile was produced in 1886The Wright brothers flew the first heavier-than-air

machine in 1903 The first diesel electric locomotive was introduced in

1921

Lindbergh flew over the Atlantic Ocean to Europe in 1927

The first diesel engine buses were used in 1938

The first limited-access highway in the United States (the Pennsylvania Turn-pike) opened in 1940

The Interstate Highway system was initiated in 1950

The first commercial jet appeared in 1958

Astronauts landed on the moon in 1969

The use of computers and automation in transportation grew dramatically through the 1960s and 1970s and continues to grow unabated

Microcomputers have revolutionized our capabilities to run programs since the 1980s and such capabilities have helped us to examine alternatives quickly and efficiently

(2) Important Role of Technology in Transportation

The fantastic spur in technology promotes the world on the upgrade, and expedites the evolution of transportation.

The acceleration of technology itself is frequently dramatized by a brief account of the progress in transportation.

(3) Development of Transportation Technologies

① ITS

The application of new technologies including ITS (intelligent transportation systems ) across the world reveals a new trend

In the past 10 years, there has been a 30% increase in traffic.

② National Intermodal Transportation System

To develop a National Intermodal Transportation System has become a basic policy in many advanced countries

The provisions of the act reflect these important policy goals.

1.2 TRANSPORTATION ENGINEERING

Transportation engineering will appeal to those who are attracted to public service and to opportunities to wrestle with challenging social problems and contribute to their solutions.

1.2.1 The Field of Transportation Engineering

The desires of people to move and their need for goods create the demand for transportation.

Transportation engineering is a multidisciplinary field drawing on more established disciplines to provide its basic framework, such as economics, geography, and statistics

1.2.2 Definition of Transportation Engineering

The Institute of Transportation Engineers (1987) defines :

the application of technological and scientific principles to the planning, functional design, operation, and management of facilities for any mode of transportation in order to provide for the safe, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods

Traffic engineering defines:

that phase of transportation engineering which deals with planning, geometric design, and traffic operations of roads, streets, and highways, their networks, terminals, abutting lands, and relationships with other modes of transportation

1.2.3 The Practice of Transportation Engineering

Transportation engineering involves a diversity of basic activities performed by such specialists as policymakers, managers, planners, engineers, and evaluators.

1.2.4 The Nature of Transportation Engineering

Transportation engineering is a multidisciplinary area of study and a comparatively new profession that has acquired theoretical underpinnings, methodological tools, and a vast area of public and private involvement.

Because of the multidisciplinary content of transportation engineering , training transportation engineers and planners use the following fields of knowledge :

economics geography

operations research regional planning

sociology psychology

probability statistics

customary analytical tools of engineering

Transportation Planning

Traffic Engineering

Social Sciences

Economics

Planning and architecture System

Engineering

Civil Engineering

Math and Statistics

Physical Sciences

Geometric design

Soil mechanics

Pavement Design

Involvement

Breadth of transportation engineering

Figure 1.2 Interdisciplinary breadth and depth of transportation engineering

soft

hard

1.2.5 Civil Engineering Involvement in Transportation

Transportation engineering is more commonly used or refer to a subspecialty of civil engineering , which includes both physical civil engineering and systems engineering .

Historically, the primary involvement of civil engineers in transportation has been in the provision of physical facilities and the devising of operating strategies for them.

Most civil engineering activity related to the provision of physical facilities is what might be called physical civil engineering;

On the other hand, most civil engineering activity related to planning and operation of the transportation system, is what might be called systems engineering.

1.3 TRANSPORTATION SYSTEM

Transportation is typically systematic engineering, a set of interrelated parts.

The transportation system is organized around society’s need to provide an adequate service and involves broad interaction with many other disciplines.

The goals of the transportation system are primarily economic; the most important constraints it faces are environmental.

1.3.1 Scope and Functional Organization of transportation system

Transportation is one of the major functional systems of modern society.

The transportation system is a functional system in the context of society as a whole, and is a major functional system.

The economic scope of the transportation system is indicated by the fact that in 1998, transportation accounted for 11.2 percent of the gross domestic product and 19 percent of the average household expenditures in the United States.

The transportation system is a major source of resource consumption and environmental impact.

Transportation accounts for almost two-thirds of the petroleum consumption in the United States and is a major contributor to environmental problems such as air pollution, noise, and destruction of natural habitats.

Components

Physical facilities, including streets, roads, and highways; railroads, airports, sea and river ports pipelines, and canals

Fleets of vehicles, vessels, and aircraft Operating bases and facilities, including vehicle

maintenance facilities and office space Organizations Operating strategies, including vehicle routing

scheduling, and traffic control

Figure 1.3 Interrelationship of functional components

of a commercial air transportation system

FAA(Facility-oriented organization)

MPOs(Facility-oriented organization)

Airport Authorities(Facility-oriented organization)

Funding

Safety regulation

Airtines (OperatingOrganization)

Funding planning

Terminal

MaintenanceFacilities

(Operating bases)

Operate

Own

RunwaysTaxiways

Use

Aircraft(Fleets)

Own/operate

RouteStructure

Schedule

Operating politics

(Operating strategies)

Operating plans

Airport(Physical Facilities)

Tower

Airport traffic control

Traffic control

Terminal area and en route traffic control

Tenant operations

(ticking, etc.)

Determine

Figure 1.3 illustrates the ways in which the functional components of the commercial air transportation system are interrelated.

1.3.2 The Systems Approach

The systems approach has been applied successfully in transportation engineering and represents a broad-based and systemic ways and means and is a problem-solving philosophy used particularly to solve complex problems.

System analysis is the application of the scientific method to the solution of complex problems and the act of studying business or industrial operations to plan ways of carrying them out, improving them etc.

1.3.3 Overview of Transportation Systems Characteristics

Elements of Transportation systems:

Links

Vehicles

Terminals

Management and labor

Links

the roadways or tracks connecting two or more points. Pipes, beltways, sea-lanes, and airways can also be considered as links

Vehicles the means of moving people and goods from one

node to another along a link. Motorcars, buses, ships, airplanes, belts, and cables are examples

Terminals

the nodes where travel and shipment begins or ends. Parking garages, off-street parking lots, loading docks, bus stops, airports, and bus terminals are examples

Management and labor

the people, who construct, operate, manage, and maintain the links, vehicles, and terminals

Relations among the elements, human and environment

These four elements interact with human beings, as users or nonusers of the system, and also with the environment.

The behavior of the physical, human, and environmental subsystems is highly complex because it involves interaction of people as drivers, riders, and non-riders, using vehicles of differing character and performance on links with diverse vehicle characteristics in a myriad of environmental conditions.

Categories of human behavior affected by transportation

Locomotion (passengers, pedestrians) Activities (e.g., vehicle control, maintenance,

community life) Feelings (e.g., comfort, convenience, enjoyment, stress,

likes, dislikes) Manipulation (e.g., modal choice, route selection,

vehicle purchase)

Health and safety (e.g., accidents, disabilities, fatigue)Social interaction (e.g., privacy, territoriality, conflict,

imitation) Motivation (positive or aversive consequences,

potentiation) Learning (e.g., operator training, driver education,

merchandising) Perception (e.g., images, mapping, sensory thresholds)

Physical environment impacting human behavior Spatial organization: This dimension often includes the shape, scale,

definition, bounding surfaces, internal organization of objects and society, and connections to other spaces and settings. Indeed, this is the dimension that most people are referring to when they talk about the physical environment.

Circulation and movement:

This property includes people, goods, and objects used for their movement----cars, trains, highways, and rails--and also the forms of regulating them, such as corridors, portals, turnstiles, and open spaces.

Communication:

Both explicit and implicit signals, signs or symbols communication, required behavior, responses, and meanings are covered by this dimension; in essence, these are the properties of the environment that give users information and ideas.

Ambience:

This dimension usually includes such items as microclimate, light, sound, and odor. Those features of the environment that are critical for maintaining the physiological and psychological functioning of the human organism are included.

Visual properties:

The environment as it is perceived by its users is generally implied by this property and includes color, shape, and other visual modalities.

Resources:

The physical components and amenities of a transportation system---paths, terminals, and vehicles---could be included. The measures of these resources could embrace such dimensions as the number of lanes or the square footage of the terminals.

Symbolic properties:

The social values, attitudes, and cultural norms that are represented or expressed by the environment fall into this category.

Architectonic properties:

This refers to the sensory or aesthetic properties of the environment.

Consequation:

This is that characteristic of the environment that strengthens or weakens behavior. Measures of consequation include such items as costs, risks, and congestion.

Protection:

Safety factors in general are implied in this category.

Timing:

All the items mentioned before are scheduled in time and some of them fluctuate with various cyclical rhythms, such as daily, weekly, or hourly timings.

Table 1-1 Relation between aspects of transportation and their effects on people (1)

Activities Locomotion Social

Interaction Feelings perception

Spatial organization X X

Circulation and movements X X X

Communication X X X

Ambience X X

Visual properties X

Resources X X

Symbolic properties X X X

Architectural properties X X X X

Consequation X

Projection

Timing X X

Environmental aspects

Human Behavior

Table 1-1 Relation between aspects of transportation and their effects on people

Motivation Healthy and

safety Learning Manipulation

Spatial organization X

Circulation and movements X X

Communication X

Ambience X X X

Visual properties

Resources X X X

Symbolic properties X X

Architectural properties X X X

Consequation X X X

Projection X X

Timing

Environmental aspects

Human Behavior

Parameters to evaluate the transportation systems

Ubiquity

Mobility

Efficiency

Ubiquity

The amount of accessibility to the system, directness of routing between access points, and the system’s flexibility to handle a variety of traffic conditions.

Highways are very ubiquitous compared to railroads, the latter having limited ubiquity as a result of their large investments and inflexibility.

Mobility

The quantity of travel that can be handled. The capacity of a system to handle traffic and speed are two variables connected with mobility.

A freeway has high mobility, whereas a local road has low mobility. Water transport may have comparatively low speed, but the capacity per vehicle is high. On the other hand, a rail system could possibly have high speed and high capacity.

Efficiency

The relationship between the cost of transportation and the productivity of the system. Direct costs of a system are composed of capital and operating costs, and indirect costs comprise adverse impacts and unquantifiable costs, such as safety. Each mode is efficient in some aspects and inefficient in others.

The classification of transportation modes into different operational systems or functional classes is useful in understanding the complexity of the total transportation system.

1.3.4 Transportation Systems, Hierarchies, and Classification

Hierarchy

Primary movementTransition

Distribution

Collection

Terminal access

Figure1.5 Hierarchy of Movement

There is a close connection between access, mobility, and the functional classification of streets and highways.

A typical urban area street distribution is shown in Table 1.2.

Table 1.2 Typical Distribution of Urban Functional Systems

System Range

Travel Volume (%) Milcage (%)

Principle arterial 50 5

Minor arterial 25 10

Collector street 5 10

Local street 20 75

Total 100 100

An example of a graphical analysis is shown in Figure 1.6.

Figure 1.6 Vehicle-Miles of Travel by Street Class

Arterials Miles 8.0%Travel 73.0%

Miles 8.0%Travel 73.0%

Miles 33.0%Travel 92.0%Collectors Miles 25.0%Travel 19.0%

Local roads Miles 67.0%Travel 8.0%

1.3.5 Objectives and Constraints of Transportation Systems

Motives for transportation systems:

military

political , or economic bases

This leads to two major conclusions about the economic role of transportation systems:

an adequate transportation infrastructure is necessary

for a high level of economic activity to exist.

First

most transportation is not something undertaken

for its own sake, but is what is referred to as a secondary good, whose value depends

on the value of the goods transported or the services performed by passengers at

their destinations.

Second

Constraints

Public policy places a number of constraints on the transportation system, which may be seen in some cases as diminishing its economic efficiency. The most obvious of these are constraints related to environmental concerns, in the broad sense of anything that impacts the “human environment”.

Transportation system is organized around society’s need and involves broad interaction with many other disciplines.

1.3.6 Transportation Policy Making

Figure 1.7 Transportation System Model: Transportation Processor

Activity subsystem

Physical subsystem

Human subsystem

Inputs

LandLaborCapital

MaterialsInformation

Outputs

Transportation system model

The physical subsystem consists of vehicles, pavements, tracks, rights-of-way, terminals, and other manufactured or natural objects. The activity subsystem includes riding, driving, traffic control, and so on.

Outputs from the system include the movement of people and goods and improvement or deterioration of the physical environment.

Reason for people and goods to move:

complementarity, the relative attractiveness between two or more destinations

the desire to overcome distance, referred to as transferability, measured in terms of time and money needed to overcome this distance and the best technology available to achieve this

intervening opportunities to competition among several locations to satisfy demand and supply

1.3.6.2 Land Use and Transportation Cycle

Accessibility

Transportation facility

Transportation needs

Trips

Land use

Land value

Figure 1.8 Land Use/Transportation Cycle

1.3.6.3 Distance and Transportation Mode Choose

Distances choose:

walking for short distances

car for medium distances

airplane for long distances

The demand for speed depends on the distance traveled, long distances mean greater speed.

Table 1.3 Transport Function Concept

Connection between distance and time

Distance,d (km)

Time,t (min)*

Theoretical TransportSpeed (km/hr) Transport Alternative

0.4 5 4.8 Walking

1 6.6 9.1 Bus (town center)

4 10 24 Streetcar or bicycle

10 13.2 45.5 Car (urban or suburban)

40 20 120 Highway

100 26.4 228 Train or airplane

1,000 52.8 1,140 Jet

Figure 1.9 Relationship between Human Trip and Artificial Media with Social Flow of

Social flow

Noninformation flow(energy, commodity)

Human trip Artificial media

Mail messengerTelecommunication

(electronic media)

TelephoneTelegramTeletypeTelevision (graphic display) Teleprint (facsimile)

Information flow

(transportation)Car, rail, plane, ship

(nontrip)Noneletromic media

Table 1.4 Speeds and modes

Mode Speed (mph) Factor (approx)

Army (on foot) 0.5 4.50/ ＝ 0.5

Wagon, coach, sailing ship 2.25 4.51/2 ＝ 2.25

Early steamship 10 4.52/2 ＝ 10.13

Car, train 45 4.53/2 ＝ 45.56

Propeller plane 200 4.54/2 ＝ 205.03

Jet plane 900 4.55/2 ＝ 922.64

Missile 4,000 4.56/2 ＝ 4,152

Orbiting satellite 18,000 4.57/2 ＝ 18,683

Telecommunication Speed of light 4.514/2 ＝ 1.396×109

1.3.7 Transportation and Transportation-Related Problems

Fatal accidents, injuries, and property damage are on

the rise everywhere, although there seems to be little that is really accidental in most accidents.

Public transportation usage is on the decline despite governmental intervention and high subsidization.

Transportation systems have a major impact on the environment.

1.3.8 Transportation and Sustainability

The connection between transportation and sustainability is recognized worldwide.

Vehicles or vessels

Persons and/or goods

Activity system Built infrastructure

Figure 1.10 A basic model connection vehicles/vessels, persons/goods, and the built infrastructure

CCCC

the infrastructure, which includes a variety of fixed installations such as roads and streets, railroads, pipelines, canals, airports, and harbors

persons and/or goods that need

to be transported

AAAA motor vehicles or rail cars or water vessels that are used to move people and/or goods

BBBB

basic interactions between three essential components:

The end of CH1

QUESTIONS

What is the definition of transportation? What are the main purposes of the

courses like transportation engineering? List the milestone events in the

development of transportation engineering.

Why is it said that transportation engineering is a multidisciplinary field?

What is a system? How to understand that transportation is typically systematic engineering?

What are the primary components of a transportation system?

What are the basic attributes usually used to evaluate transportation systems?

Is distance one of the most pivotal factors in transportation planning? How does it affect transportation mode choosing?

QUESTIONS

JOKE

巡逻警察发现 , 有辆汽车每跑 10米左右 , 便要上下颠簸一下。

于是，他发动摩托车追上去截住了那辆汽车：“您的车怎么啦？”

司机满脸惶恐：“没，没什么，巡逻官先生，我，我老打嗝。”

JOKE

彼尔和本喝醉了。他们上了公共汽车。彼尔说：“我来买票。”本说：“还是我来买吧。”他把彼尔推到一个座位上。本把钱递到一个身穿蓝制服的人面前，说：“买两张到博物馆的票。”那人没有接钱。他气愤地对本说：“别给我钱，我是个海军军官。”本打量了这人一会儿，然后对彼尔喊道：“过来，咱们下去。我们搞错了！这不是汽车是轮船。”

JOKE

Traveler: Can I catch the three o’clock train to Washington?

Ticket Agent: That depends on how fast you can run. It left fifteen minutes ago.