Traffic & Highway Engineering Text Book. Fourth Edition, SI Nicholas J. Garber Lester A. Hoel 2010

Transcription

1 Traffic & Highway Engineering Text Book Fourth Edition, SI Nicholas J. Garber Lester A. Hoel 2010

2 Chapter 2 Transportation Systems and Organizations

3 Chapter 2 Transportation System & Organization Developing a Transportation System Modes of Transportation Transportation Organization

4 Chapter 2 Transportation Systems and Organizations SUMMARY The transportation system in a developed nation consists of a network of modes that have evolved over many years. The system consists of vehicles, guide ways, terminal facilities, and control systems; these operate according to established procedures and schedules in the air, on land, and on water. The system also requires interaction with the user, the operator, and the environment.

5 Chapter 2 Transportation Systems and Organizations SUMMARY The passenger or shipper thinks of each mode in terms of the level of service provided. Each mode offers a unique set of service characteristics at a given price: travel time, frequency, comfort, convenience, reliability, and safety. The traveler or shipper selects the mode based on how these attributes are valued.

6 Chapter 2 Transportation Systems and Organizations Comparative Advantages of Transportation Modes Students are requested to read this topic and to discuss it in the next lecture

7 Chapter 2 Transportation Systems and Organizations Example 2.1 Selecting a Transportation Mode (p29) An individual is planning to take a trip between the downtown area of two cities, A and B, which are 400 km apart. There are three options available: Travel by air. This trip will involve driving to the airport near city A, parking, waiting at the terminal, flying to airport B, walking to a taxi stand, and taking a taxi to the final destination.

8 Chapter 2 Transportation Systems and Organizations Example 2.1 Selecting a Transportation Mode (continued) Travel by auto. This trip will involve driving 400 km through several congested areas, parking in the downtown area, and walking to the final destination. Travel by rail. This trip will involve taking a cab to the railroad station in city A, a direct rail connection to the downtown area in city B, and a short walk to the final destination.

9 Chapter 2 Transportation Systems and Organizations Example 2.1 Selecting a Transportation Mode (continued) It is a business trip The traveler is willing to pay $25 for each hour of travel time reduced Mode cost $ time (hours) Air Auto Rail Which mode is selected based on travel time and cost factors alone? What other factors might be considered?

10 Chapter 2 Transportation Systems and Organizations Solution: Since travel time is valued at $25/hr, the following costs would be incurred: Air: (5) = $375 Auto: (8) = $400 Rail: (12) = $450 In this instance, the air alternate reflects the lowest cost and is the selected mode. Other factors: Safety, reliability and convenience.

11 Chapter 2 Transportation Systems and Organizations 2.2 MODES OF TRANSPORTATION Freight and Passenger Traffic Intercity freight transportation Principal mode: Highways (truck) Railroads Water pipelines

12 Chapter 2 Transportation Systems and Organizations 2.2 MODES OF TRANSPORTATION Intercity passenger transportation Principal mode: Highways (automobile) Air Transit (bus) Railroads

13 Chapter 2 Transportation Systems and Organizations SUMMARY The evolved transportation system has produced a variety of modes that complement each other. Intercity passenger travel often involves auto and air modes; intercity freight travel involves pipeline, water, rail, and trucking. Urban passenger travel involves auto or public transit; urban freight is primarily by truck.

14 Chapter 2 Transportation Systems and Organizations The principal carriers of freight are rail, truck, pipeline, and water. Passenger transportation is by auto, air, rail, and bus. Highway transportation is the dominant mode in passenger travel. The United States highway system comprises 6.3 million km of roadway.

15 Chapter 2 Transportation Systems and Organizations

16 Chapter 2 Transportation Systems and Organizations Public Transportation Transit services available to urban and rural residents Transit modes: Mass transit (buses, light rail, rapid transit) Paratransit (taxi, car rental, dial-a-ride..) Ridesharing (carpool, vanpool, share-ride taxi)

17 Chapter 2 Transportation Systems and Organizations Do people prefer to use public transportation? distance from bus stops long waits at bus stops changing buses long journey time inconvenience on bus

18 Chapter 2 Transportation Systems and Organizations Highway Transportation Highway transportation is the dominant mode in passenger travel and one of the principal freight modes.

19 Solved Examples Mode Selection

20 Chapter 2 Garber P29 Transportation System Comparative Advantages of Transportation Modes Example 2.1 Selecting a Transportation Mode (Garber p29) An individual is planning to take a trip between the downtown area of two cities, A and B, which are 400 km apart. There are three options available: Travel by air. This trip will involve driving to the airport near city A, parking, waiting at the terminal, flying to airport B, walking to a taxi stand, and taking a taxi to the final destination.

21 Chapter 2 Garber P29 Example 2.1 -cont. Travel by auto. This trip will involve driving 400 km through several congested areas, parking in the downtown area, and walking to the final destination. Travel by rail. This trip will involve taking a cab to the railroad station in city A, a direct rail connection to the downtown area in city B, and a short walk to the final destination.

22 Chapter 2 Garber P29 Example 2.1 -cont. It is a business trip The traveller is willing to pay $25 for each hour of travel time reduced 1. Which mode is selected based on travel time and cost factors alone? 2. What other factors might be considered?

23 Chapter 2 Garber P29 Example Solution: Since travel time is valued at $25/hr, the following costs would be incurred: Air: (5) = $375 Auto: (8) = $400 Rail: (12) = $450 In this instance, the air alternate reflects the lowest cost and is the selected mode. Other factors: Safety, reliability and convenience.

24 Transportation Systems and Organizations Highway Project Development Process

25 Chapter 2 Transportation Systems and Organizations Highway Transportation The Highway Project Development Process 1. Planning (6 to 24 months) 2. Design (15 to 24 months 3. Environment (9 to 36 months) 4. Right-of-Way (6 to 21 months) 5. Construction (12 to 36 months) Thus, total project time can range from 4 to 12 years, depending on the physical characteristics, scope, and community support for the project.

26 Chapter 2 Transportation Systems and Organizations Six-step process for transportation projects: 1. Select Project 2. Investigate Alternates 3. Obtain Final Approval 4. Develop Project Design 5. Prepare for Construction 6. Construct the Project

27 Chapter 2 Transportation Systems and Organizations Cost of highways.. Estimate the cost of building 1km length of a 30m wide road. Sources of Funds for Highways 1. Highway users (direct taxes) 2. Property owners 3. Government (general taxes)

28 Solved Example Highway Finance

29 Chapter 2 Garber P33 Example 2.2 Computing the Toll to Maximize Revenue Using a Supply- Demand Curve : A toll bridge carries 5000 veh/day. The current toll is 150 cents. When the toll is increased by 25 cents, traffic volume decreases by 500 veh/day. Determine the amount of toll that should be charged such that revenue is maximized. How much additional revenue will be received?

30 Chapter 2 Garber P33 Example Solution: Let x = the toll increase in cents. Assuming a linear relation between traffic volume and cost, the expression for V is:

31 Chapter 2 Garber P33 Example Solution:

32 Chapter 2 Transportation Systems and Organizations Figure 2.7 Dwight D. Eisenhower System of Interstate and Defense Highways

33 Chapter 2 Transportation Systems and Organizations Figure 2.8 National Highway System

34 Chapter 2 Transportation Systems and Organizations

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36 Chapter 2 Transportation Systems and Organizations Transportation Organizations 1. Private Transportation Companies 2. Regulatory Agencies 3. Federal Agencies 4. State and Local Agencies and Authorities 5. Trade Associations 6. Professional Societies 7. Users of Transport Services

37 Chapter 2 Transportation Systems and Organizations Comparative Advantages of Transportation Modes Students are requested to read this topic and to discuss it in the next lecture

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39 Roads and highway network

40 Roads and highway network principal types of road pattern in urban areas. Gridiron Linear pattern Radial pattern

41 Roads and highway network Gridiron Advantages: 1. Easier for surveyors to set out, using straight lines and rectangular coordinates. 2. It encourages an equal spread of traffic over the grid, therefore, the impact at particular location is reduced. 3. It facilitates the implementation of one-way street systems. 4. If there is a central business area in the middle of the grid, it is easy for through traffic to bypass it. Disadvantages: 1. Extra distances must be travelled when going in a diagonal direction. 2. Providing a diagonal route has an unfortunate effect on the buildings producing acute angles.

42 Roads and highway network Gridiron Omar Elmokhtar Example of Gridiron System Part of Gaza

43 Roads and highway network Linear pattern Advantages: 1. Main traffic flow is canalised into one major roadway. Disadvantages: The major roadway serves as a route both to the completely internal traffic and for the internal-external traffic as well as for external-internal and through traffic... This leads to congestion and the major roadway becomes overloaded.

44 Roads and highway network Linear pattern Example of Linear System Part of Nabuls

45 Roads and highway network Radial pattern Moscow city

46 Roads and highway network Radial pattern Mainly in old cities Advantages: Providing a direct access to the town centre. Disadvantages: 1. Concentration of traffic generators within the central area 2. Radial roads converging on the main sources of attraction 3. Lack of suitable bypass routes for through traffic.

47 Chapter Roads and highway network Radial pattern Example of radial System Part of London

48 Roads and highway network Radial pattern Example of radial System Erbil, Iraq

49 Road classification

50 Road classification (road hierarchy concept) Road classification Roads are classified as follows: In the USA Arterials: Principal (freeways) Minor Collector streets Local streets Source: O Flaherty (2006), page 140

51 Road classification See Table 6.5, O Flaherty (2006), page 142 Urban Roads are classified as follows: In the UK Primary Distributor District Distributor Local Distributor Access roads Pedestrian streets Rural Roads are classified as follows: In the UK Primary Routes (motorways) Secondary roads: A roads B roads Source: O Flaherty (2006), page 141

52 Chapter Road classification Source: O Flaherty (2006), page 142

53 Road classification Source: O Flaherty (2006), page 142

54 Road classification Source: O Flaherty (2006), page 142

55 Road classification In Gaza (Palestine): Main Road Serves for national or inter district traffic Regional road Branching off from, or lining, main roads Access Road Leading from a main or regional road to a certain point within a locality

56 Road classification

57 Roads in Gaza Read حالة الطرق المرورية في قطاع غزة - مشاكل وتوصيات أ. د. محمد علي الكحلوت مجلة جامعة الملك سعود شبكة النقل البري في مدينة غزة رسالة ماجستير عام 2012 للباحث أحمد يوسف شبات

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