CE 402 Transportation Engineering

CE 402 Transportation

Engineering

Life in communities has changed over the years.

One of those changes is in transportation.

Transportation is a way of moving people or things from one place to another.

Transportation

Land

Water

Air

Modes of Transportation

Modes of Transportation

There are three main elements of automobile transportation: The road users (Drivers and pedestrians) The vehicle The road way and geometric design

Elements of Transportation

LOCATION SURVEY AND CONTROLS

Art of observing and making measurements of relative portions of natural and manmade features on the surface of earth and plotting these measurements to some suitable scale to form a map.

SURVEY

Highway surveys involve measurement and calculation of distances, angles (horizontal andvertical) and elevations. The data is then used to form a base map

with contour lines and longitudinal cross-sections.

SURVEY FOR A HIGHWAY

Three major categories1. Ground SurveysBasic equipment is used for location survey Measuring Tape. Levels. Theodolite. Electronic distance measuring devices

(EDM’s).

SURVEYING TECHNIQUES

2. Remote Sensing Measurement of distances and elevations

by using devices located above the surface of earth.

Data is collected through airplanes and satellites using global positioning systems (GPS).

Photogrammetry (data is obtained with the help of aerial photographs) is the most commonly used technique.

3. Computer Graphics Available/collected data is compiled and

stored in the electronic form. Photogrammetric and general survey data

is combined digitally with the help of softwares.

The files can then be plotted in the form of maps.

Location controls are basically the factors that effects the selection of location of a highwayMajor factors are: Topography. Soil Characteristics. Environmental factors (noise and air

pollution). Economic factors.

LOCATION CONTROLS

Highway location process have four phases Desk study of available data/information Reconnaissance survey Preliminary location survey Final location survey

HIGHWAY LOCATION SURVEY/PROCESS

Available data in the form of reports, maps,aerial photographs and charts is studied.

Data is obtained form government authorities e.g. transport department (NHA), geological survey of Pakistan etc.

Similarly, information is required to be obtained on hydrology, mining, agriculture and weather.

DESK STUDY OF AVAILABLE DATA

Data is obtained on the following characteristics: Engineering (topography, geology, traffic

volume and climate) Social (land use trends and zoning) Environmental (air, noise and water

pollution, wildlife, historic and archaeological sites)

Economic (construction cost, agricultural, commercial and industrial trends)

DESK STUDY OF AVAILABLE DATA

“Reconnaissance is the process of identifying several possible routes & evaluating the feasibility of these routes for a highway between specific points” Aerial photographs are often used for the

purpose, especially for rural areas.

RECONNAISSANCE SURVEY

Feasible routes are identifies by keeping in mind the following factors Terrain and soil conditions. Serviceability of route to industrial and

residential areas. Crossing of other transportation facilities

like rivers, rail and highways. Route directness.

Identification of control points for each feasible/selected route.

Routes are then plotted on a map.

The position of the feasible routes are set as closely as possible by Establishing all control points. Determining preliminary vertical and

horizontal alignments of each control point Economic and environmental feasibility of

the routes The best route is then selected as the

preliminary alignment for the highway.

PRELIMINARY LOCATION SURVEY

Initial cost of the project and future economic effects

Road user cost Construction cost Road user benefits Economic drawbacks from the projectInformation also helps in deciding the type of highway for a particular route.

Economic Evaluation

Environment Includes plant animals Human community Effects on quality of life for all (animals and

human being)

Environmental Evaluation

An environmental impact statement should be submitted which should include Available alternatives Assessment of all positive and negative impacts Short and long term effects Unavoidable adverse environmental effects Use of natural resources Each route should be studied

e.g. Positive and negative effects of at grade or grade seperated intersection.

Environmental Evaluation

Detailed layout of the selected route is carried out at this stage Centreline of the road. Horizontal and vertical alignment. Property lines. Intersecting roads. Position of structures and drainage

channels.

FINAL LOCATION SURVEY

Factors that effect location of highway in urban areas Connection to local streets (which street to

connect,traffic flow) Right-of-way acquisition (land cost, road on

elevated structures, noise and aesthetics) Coordination with other transportation systems(integrated system, public transport) Provisions for bicycles and pedestrians

(sidewalks,crosswalks, traffic control devices, ramps, bicycle path)

LOCATION OF HIGHWAY IN URBAN AREAS