Transportation Engineering PDF
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This document provides an overview of transportation engineering, detailing its history and importance. It covers different modes of transportation, and things to consider when developing a transportation system. The document also touches on concepts like transportation planning and the four-step travel demand model.
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TRANSPORTATION ENGINEERING Week1 Introduction, The Transportation Engineering and its development Transportation is essential for a nation’s development and growth. In both the public and private sector, opportunities for engineering careers in transportation are exciting and rewarding. Elements a...
TRANSPORTATION ENGINEERING Week1 Introduction, The Transportation Engineering and its development Transportation is essential for a nation’s development and growth. In both the public and private sector, opportunities for engineering careers in transportation are exciting and rewarding. Elements are constantly being added to the world’s highway, rail, airport, and mass transit systems, and new techniques are being applied for operating and maintaining the systems safely and economically. Many organizations and agencies exist to plan, design, build, operate, and maintain the nation’s transportation system. HISTORY: River Boat (3500 BC) Wheel On Carts (3500 BC) Horses (2000 BC) Paddle Wheel Steam Boat (1783) Hot Air Balloon (1783) Steamboat (1787) 1794, First Toll Road, The Lancaster Turnpike, Pa 1807, Fulton Tested A Steam Boat On Hudson River 1869, First Transcontinental Railroad 1903, First Flight of Wright Brothers 1956, Interstate Highway System Began 1969, Men Landed on The Moon and Returned 1972, Bart Completed 1992, ITS 1998, Electric Cars Now High Speed Rail, Driverless Car, AHS, Solar Highway IMPORTANCE OF TRANSPORTATION To transfer messages and information. Without well- developed transportation systems, logistics could not bring its advantages into full play. It facilitates trade, exchange and travels. It prevents regions to be largely isolated with each other. It allows people to move to new areas. It allows people to get to their destination. DIFFERENT MODES OF TRANSPORTATION IN THE DEVELOPMENT OF THE OTHER COUNTRY: MODES OF TRANSPORTATION is a term used to distinguish substantially different means of conveyance. each mode of transport has a fundamentally different technological solution, and some require a separate environment. ROAD TRANSPORT it is relatively cheaper mode of transport as compared to other modes. perishable goods can be transported at a faster speed by road carries over a short distance. AIR TRANSPORT it is the safest and most convenient mode of transport during natural calamities. it is very useful in transporting goods and passengers to the area, which is not accessible by any other means. it provides vital support to the national security and defense. RAIL TRANSPORT it is a convenient mode of transport for travelling long distances. its operation is less affected by adverse weather conditions like rain, floods, fogs, etc. OTHER MODES OF TRANSPORT Cable Transport Maritime Transport Pipelines Transport THINGS TO BE CONSIDERED IN DEVELOPING THE TRANSPORTATION OF THE COUNTRY ARE: Climate Change Rapid Urbanization and Motorization Accessibility And Affordability Road Safety Air Pollution Week 2 The Highway Transportation System Moving People and Goods from Place to Place Safely and Efficiently ROADWAYS Multilane highways Country Roads Streets PEOPLE Drivers Passengers Cyclists Pedestrians VEHICLES Tractor-trailers Buses Cars, Vans, SUV’s Mopeds Motorcycles FEDERAL AND STATE REQUIREMENTS National Traffic and Motor Vehicle Safety Act Automakers are required to build certain safety features, such as safety belts and shatterproof windows, into their motor vehicles. National Highway Safety Act Guidelines: Vehicle registration, Driver Licensing, Traffic Laws, Traffic Courts, Highway Construction and Maintenance. Each state sets its own statutes or laws, that concern highway safety. READING HIGHWAY TRANSPORTATION SYSTEM SIGNS If the numbers on a highway sign are ODD, it means that the road goes North – South. An EVEN numbered sign means that the road goes East – West. Interstate numbers range from 4 to 99. The greater the EVEN number, the farther North you are. The greater the ODD number, the farther East you are. REDUCING YOUR RISK WITHIN THE HTS Keep your vehicle in top condition Anticipate the actions of others Take steps to protect yourself and others Drive only when you are in sound physical and mental condition Make a conscious effort to develop your driving skills THE IPDE PROCESS Identify Identify objects or conditions within 12 to 15 seconds ahead that could interfere with your planned path of travel. Open Closed Zones Traffic Controls Roadway features and conditions Other users Specific Clues Predict Identify objects or conditions within 12 to 15 seconds ahead that could interfere with your planned path of travel. Imagine what might happen. Path (Where might the other driver go?) Action (What action will other users take?) Space (Will I have an open zone?) Point of Conflict (Where might our paths cross?) Decide Decide what action(s) to take at least 4 to 5 seconds ahead of time to control or reduce risk. *Decision will be influenced by the speed of own vehicle as well as the speed of other vehicles* Change or maintain speed Change directions Communicate Execute Carry out your decision to avoid conflict is the execute step in the IPDE process. *This step involves the physical skills used in driving. * Control Speed Steer Communicate Combine Actions The Smith System Aim High and Look Ahead Look way ahead of your vehicle (20 to 30 seconds ahead), not down at the road directly in front of you. Keep Your Eyes Moving Search the scene constantly for changes that might require you to adjust your speed or position. Get the Big Picture Search the whole scene, not just part of it. Make Sure Others See You Communicate with drivers and pedestrians. Leave Yourself a Way Out Always leave yourself a path of escape (a way to avoid a collision) HOW VISION AFFECTS YOUR ABILITY TO DRIVE Visual Acuity – clear vision Field of Vision Central Vision – the narrow cone-shaped area directly in front of you Peripheral Vision – angles to your right and left Vertical Field of Vision – up and down Depth Perception – gives a 3-dimensional perspective to objects (distance judgment) Week 3 TRANSPORTATION PLANNING Transport planning is defined as planning required in the operation, provision and management of facilities and services for the modes of transport to achieve safer, faster, comfortable, convenient, economical and environment-friendly movement of people and goods. PURPOSE OF TRANSPORTATION PLANNING Identifying multiple options for transportation Identifying outlying problems to a transportation system Identifying possible solutions to those identified transportation system Optimization of existing transportation systems and structural design IMPORTANCE OF TRANSPORTATION PLANNING Obsolete road designs, roadside hazards, and substandard road conditions can cause highway fatalities in different areas of the country. Effective transport in urban areas is essential to the accessibility of land, growth of the economy, and the overall environment of the city. These hazards should be routinely monitored and fixed for the betterment of the people. PLANNING PROCESS 1. Situation Definition Involves all of the activities required to understand the situation that gave rise to the perceived need for a transportation improvement Examples: Inventory transportation facilities Measure travel pattern Review prior studies 2. Problem Definition To describe the problem in terms of objectives to be accomplished by the project and to translate those objectives into criteria that can be quantified. Objectives are statements of purpose such as o to reduce traffic congestion, o to improve safety in a particular road o to maximize net highway-user benefits and; o to reduce noise 3. Search for a Solution In this phase of the planning process, consideration is given to variety of ideas, design, location, and system configuration that might provide solution to the problem. This is the brainstorming stage, in which many options may be proposed for later testing and evaluation. 4. Analysis of Performance The purpose of performance analysis is to estimate how each of the proposed alternatives would perform under present and future conditions. Included in this step is a determination of the investment cost of building the transportation project, as well as annual costs for maintenance and operation. Example: For each option or proposed solution, determine the costs of the implementation of the project, how will the traffic flow be affected, and the impact this proposal will have on the consumers. 5. Evaluation of Alternative The purpose of the evaluation phase is to determine how well each alternative will solve the main objectives of the project. The performance data produced in the analysis phase are used to compute the benefits and costs that will result if the project is selected. Example: For a bridge project, determine The benefits of the project versus the costs required to do the project. The profitability of the project from the future consumers. Cost-effectiveness of the project 6. Choice of Project This part of the planning process is made after carefully considering all the factors that may or may not contribute to the project. Example: Consider factors involved Revenue Cost Forecast Site Location Political Judgement 7. Specification and Construction Once the transportation project has been selected, the project can proceed into the detailed design phase in which each of the components of the facilities is specified Example: Designing the bridge. Contractor selections. Transfer of completed bridge to authority for operation and maintenance. URBAN TRANSPORTATION PLANNING Urban transportation planning involves the evaluation and selection of highway or transit facilities to serve present and future land uses. For example, the construction of a new shopping center, airport, or convention center will require additional transportation services. Also, new residential development, office space, and industrial parks will generate additional traffic, requiring the creation or expansion of roads and transit services. Urban transportation planning is concerned with two separate time horizons; SHORT TERM LONG TERM SHORT TERM This type of planning pertains to different matters regarding transportation within a certain area that can be accomplished within three (3) years. These projects are designed to provide better management of existing facilities by making them as efficient as possible. Short-term projects involve programs such as traffic signal timing to improve flow, car and van pooling to reduce congestion, park-and-ride fringe parking lots to increase transit ridership, and transit improvements. LONG TERM This type of planning is more structured and complex. It requires thorough inspection and planning better than short term planning. This type of planning usually is accomplished with five (5) or more years. Long-term projects involve programs such as adding new highway elements, additional bus lines or freeway lanes, rapid transit systems and extensions, or access roads to airports or shopping malls. Establishment of Goals and Objectives The urban transportation study is carried out to develop a program of highway and transit projects that should be completed in the future. Thus, a statement of goals, objectives, and standards is prepared that identifies deficiencies in the existing system, desired improvements, and what is to be achieved by the transportation improvements. Example: if a transit authority is considering the possibility of extending an existing rail line into a newly developed area of the city, its objectives for the new service might be to maximize its revenue from operations, maximize ridership, promote development, and attract the largest number of auto users so as to relieve traffic congestion. Generation of Alternatives In this phase of the urban transportation planning process, the alternatives to be analyzed will be identified. It also may be necessary to analyze the travel effects of different land-use plans and to consider various lifestyle scenarios. The options available to the urban transportation planner include various technologies, network configurations, vehicles, operating policies, and organizational arrangements. Estimation of Project Cost and Travel Demand This activity in the urban transportation planning process involves two separate tasks. The first is to determine the project cost, and the second is to estimate the amount of traffic expected in the future. The estimation of facility cost is relatively straightforward, whereas the estimation of future traffic flows is a complex undertaking requiring the use of mathematical models and computers. Week 4 Forecasting travel demands, trip generation and distribution, estimating freight demand. Forecasting travel demand Is a key component of the transportation engineer’s technical repertoire. It allows the engineer to predict the volume of traffic that will use a given transportation element in the future, whether that element is an existing highway or a potential-rail route. Four-Step Travel Demand Model Originally developed in the 1950’s and 1960’s when planning major highway facilities Four decisions are the basis of the traditional travel demand model: o The choice and reason to travel o The destination to travel o The mode by which to travel o The route on which to travel Forecasting travel demands Divided process into 4 steps: Trip Generation Trip Distribution Mode Split Trip Assignment Trip generation and distribution Trip generation Is the first stage of the classical first-generation aggregate demand models. It aims at predicting the total number of trips generated and attracted to each zone of the study area. In other words, this stage answers the questions to “how many trips” originate at each zone. Trip purpose Shopping Work Recreational - Social School Serving passengers (picking up and dropping off). Factors Govern Trip Generation Income Car ownership Family size and composition Land use characteristics Distance of zone from the town center Accessibility to public transport system and its efficiency Employment opportunities Trip distribution Is a model of the number of trips that occur between each origin zone and each destination zone. these models try to mathematically describe the destination-choice phase of the sequential demand analysis procedure. it uses the predicted number of trips originating in each origin zone (trip production model) and the predicted number of trips ending in each destination zone (trip attraction model). Factors which affect the number of trips between two zones: The number of trips produced by the origin zone. The degree to which the in-site attributes of the destination zone attract trip makers. The factors that inhibit travel between a pair of zones. Measures of Transportation Demand The contribution factors to total freight volumes might be significantly different by mode. Most demands for freight transportation are predisposed to use a particular mode, based on commodity type, value, weight or size, origin and destination location and urgency. This assumption is further supported when one notes that many carries provide several “tires” of service tide to price, speed and service guaranties to ensure their freight costumers don’t find the need to choose other services. Rail Tonnage These annual statistics, gathered and made public by the Association of American Railroads (AAR) provides a basic measure of the weight of the goods transported, regardless of distance between their extraction, production, or importation supply points and utilization, consumption, or exportation demand location. Rail Ton-Miles Railroads use net ton-miles (net weight of freight, vs. gross which includes the weight of the rail equipment itself) as the primary tally of their productive operation. With a combination of higher terminal and train building costs, the rail mode tends to concentrate on longer hauls of freight than trucking. Rail Train-Miles Since railroad freight, as well as the equipment used to carry it, moves between stations and terminals in trains, it is also useful to measure train-miles. While train-miles increase with traffic, efficiencies can slow train-miles growth even as rail transportation demand increases. Rail Car-Miles Measuring the movement of railroad cars, as opposed to tons, provides a key insight when it is noted that for the purpose of this statistic, a car-mile refers to a mile run by a freight car or an intermodal trailer or container, with or without a load. Rail Revenue Ton-Miles (Quarterly) This is the only dependent viable included in the analysis gathered on a quarterly basis for two reasons. First, as explained above, freight transportation data is limited for the truck and waterway freight. Second is that Revenue Ton-Mile is the best metric of the railroad industry’s productive efforts and used regularly in industry financials to explain revenues. Truck Ton-Miles Surface freight moves primarily by truck. With intermodal rail capturing a moderately higher percentage of longer-distance hauls, most truck moves are less than 200 miles. Ton-miles is a good measure of how most, but not all, trucking companies price their services, as well as a proxy for the useful work trucks provide, although ton-miles aren’t particularly relevant to less-than-truckload (I.TL), package and courier freight. Truck Vehicle-Miles Besides moving up to 25-28 tons of freight, trucks of various sizes may be utilized for shorter-distance deliveries and the essential “last-mile” for transporting air freight, intermodal and even small packages. Domestic Waterway Tons In general, different kinds of freight moves on barges over domestic waterways than by railroad. Barge freight is typically heavy, low-value, and high- volume where timeliness is not important. It also typically does not move far overland to or from its waterway origination or termination because these transfers would obviate the advantages of water transportation. Domestic Waterway Ton-Miles Waterway attract freight that is extremely heavy and usually has low value relative to its weight. The origin-to-destination transportation can involve, but does not require, a long length-of-haul to be appropriate to the water mode.