Transportation engineering is a sub-discipline of civil engineering which deals with the application of technology and scientific principles to the planning, functional design, operation and management of facilities for any mode of transportation in order to provide the safe, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods (transport).
As per American Society of Civil Engineers (ASCE), there are six divisions related to tranportation engineering i.e. Highway, Air Transportation, Pipeline, Waterway, Port, Aerospace, Coastal & Ocean and Urban Transportation out of 18 technical divisions within the ASCE (1987).
The planning aspects of transport engineering relate to urban planning, and involve technical forecasting decisions and political factors. Technical forecasting of passenger travel usually involves an urban transportation planning model, requiring the estimation of trip generation (how many trips for what purpose), trip distribution (destination choice, where is the traveler going), mode choice (what mode is being taken), and route assignment (which streets or routes are being used). More sophisticated forecasting can include other aspects of traveler decisions, including auto ownership, trip chaining (the decision to link individual trips together in a tour) and the choice of residential or business location (known as land use forecasting). Passenger trips are the focus of transport engineering because they often represent the peak of demand on any transportation system.
Transportation engineering, as practiced by civil engineers, primarily involves planning, design, construction, maintenance, and operation of transportation facilities. The facilities support air, highway, railroad, pipeline, water, and even space transportation. The design aspects of transport engg include the sizing of transportation facilities (how many lanes or how much capacity the facility has), determining the materials and thickness used in pavement designing the geometry (vertical and horizontal alignment) of the roadway (or track). Beside these operations planning, logistics, network analysis, financing, and policy analysis are also important to civil engineers, particularly to those working in highway and urban transportation. Every country has some organization providing the guildelines and specifiactions for design and operation of transport systems. In USA, the National Council of Examiners for Engineering and Surveying (NCEES) list online the safety protocols, geometric design requirements, and signal timing.
Before making any sort of planning, the Engineer must take an account of the database of the area or if it is appropriate, the previous system in place. This inventory or database must include information on:
- Land use
- Transportation facilities and services
- Economic activity
- Travel patterns and volumes
- Regional financial resources
- Community values and expectations
- Laws and ordinances
These inventories help the engineer create system models to accurately forecast the future demand or conditions.
Highway engineering is an engineering discipline which involves the design, construction and maintenance of Highway Roads & Systems, urban streets as well as parking facilities. Important aspects of highway engineering include overall planning of routes, financing, environmental impact evaluation, and value engineering to compare alternatives. Traffic engineering involves planning for the volumes of traffic to be handled, the methods to accommodate these flows, the lighting and signing of highways, and general layout.Older techniques include signs, signals, markings, and tolling. Newer technologies involve intelligent transportation systems, including advanced traveler information systems (such as variable message signs), advanced traffic control systems (such as ramp meters), and vehicle infrastructure integration. Similarly, pavement and roadway engineering involves setting of alignments, planning the cuts and fills to construct the roadway, designing the base course and pavement, and selecting the drainage system. Whereas, bridge engineering involves the design of highway bridges, retaining walls, tunnels, and other structures. Engineers in this specialization:
- Handle the planning, design, construction, and operation of highways, roads, and other vehicular facilities as well as their related pedestrian realms.
- Estimate the transportation needs of the public and then secure the funding for the project.
- Analyze locations of high traffic volumes and high collisions for safety and capacity.
- Use civil engineering principles to improve the transportation system.
- Utilizes the three design controls which are the drivers, the vehicles, and the roadways themselves.
It is a branch of civil engineering concerned with the design, construction, maintenance, and operation of railways. Railway engineering includes elements of civil, mechanical, industrial, and electrical engineering. Railway engineers handle the design, construction, and operation of railroads and mass transit systems that use a fixed guideway (such as light rail or even monorails). Typical tasks would include determining horizontal and vertical alignment design, station location and design, construction cost estimating, and establishment of signalling & controlling system. Railroad engineers can also move into the specialized field of train dispatching which focuses on train movement control.
Railway engineers also work to build a cleaner and safer transportation network by reinvesting and revitalizing the rail system to meet future demands. In the United States, railway engineers work with elected officials in Washington, D.C. on rail transportation issues to make sure that the rail system meets the country's transportation needs.
Port and Harbor Engineering
Port and harbor engineers handle the design, construction, and operation of ports, harbors, canals, and other maritime facilities. A harbor (or haven) is a place for ships to enter and find shelter from storms or other natural phenomena. The modern harbor is a place where ships are built, launched, and repaired, as well as a terminal for incoming and outgoing ships. There are four principal classes of harbors; commercial, naval, fishery, and refuge for small craft. Harbor may be natural or artificial.
A port is a harbor with the necessary terminal facilities to expedite the moving of cargo and passengers at any stage of a journey. A good harbor must have a safe anchorage and a direct channel to open water, and must be deep enough for large ships. An efficient port must have enough room for docks, warehouses, and loading and unloading machinery. Geographically, a port or harbor is usually limited to a comparatively small area of usable berthing space rather than an extended coastline. Some ports along exposed coastal areas, for example, the western coast of South America, have little harbor area.
Airport Engineering encompasses the planning, design, and construction of terminals, runways, and navigation aids to provide for passenger and freight service. Airport engineers design and construct airports. They must account for the impacts and demands of aircraft in their design of airport facilities. These engineers must use the analysis of predominant wind direction to determine runway orientation, determine the size of runway border and safety areas, different wing tip to wing tip clearances for all gates and must designate the clear zones in the entire port.
Pipeline engineering embraces the design and construction of pipelines, pumping stations, and storage facilities. Pipelines are used to transport liquids such as water, gas, and petroleum products over great distances. Also, products such as pulverized coal and iron ore can be transported in a water slurry.