Introduction to SurveyingCourses > Surveying > Instruments and Distance Measurements > Introduction to Surveying
What is Surveying?
Surveying is an art of determining relative positions of points on, above or below the surface of earth by means of direct or indirect measurements of distance, direction and elevation.
Why Civil Engineers Need to Know Surveying?
- All engineering projects must begin by acquiring accurate field data.
- Civil engineering projects typically require data about the site conditions and other data in the form of topographic mapping from which base site plans are prepared.
The primary goal of provided surveying materials in this website is to acquaint civil engineering students with the BASIC surveying tools and techniques needed to collect field data.
Applications of Surveying
Uses of surveying is to prepare maps viz. engineeering map, cadastral map, photographical map, contour map, militarymap, geological map, archeological map etc.
Primary divisions of surveying
- Curvature of earth is not considered
- Line joining any 2 points is considered straight.
- Triangles formed by 3 poits are considered plane.
- It is carried out for areas less than 250 sq.km.
- Curvature of earth is considered
- Line joining 2 points is taken as curved line
- Triansles formed by 3 points are considered curved triansgles
- It is done for areas exceeding 250 sq.km
Classification of Surveying
Based on Instruments
- Chain Surveying
- Compass Surveying
- Plane Table Surveying
- Theodolite Surveying
- Tachemetric Surveying
Based on Methods
- Triangular Surveying
- Traverse Surveying
Based on Objects
- Geological Surveying
- Mine Surveying
- Archaeological Surveying
- Military Surveying
Based on Nature of Field
1. Land Surveying
- Topographical Surveying
- Cadastral Surveying
- City Survey
- Engineering Survey
2. Marine Surveying
3. Astronomical Surveying
- Length: foot and decimals, rod
- Area: square foot, square yard, acre (large area)
- Volume: cubic foot, cubic yard
- Angle: degree, min, sec, radian
Metric units (International system units, SI units)
- Length: meter
- Area: square meter, hectare (large area)
- Volume: cubic meter
- Angle: degree, min, second, radian
- 1 foot = 12 inches
- 1 yard = 3 feet
- 1 meter = 39.37 inches or 3.28 feet
- 1 inch = 2.54 cm
- 1 rod = 1 pole = 1 perch = 16.5 ft
- 1 Gunter’s chain = 66ft = 4 rods = 100links
- 1 mile = 5280 ft = 80 Gunter’s chain
- 1 fathom = 6 ft
- 1 nautical mile = 6076.12 ft
- 1 acre = 43,560 ft2
- 1 hectare = 2.471 acres
- 1 hectare = 10,000 m2
- 1˚ = 1/360 circle (angle subtended by 1/360 of the circumference of a circle )
- 1˚ = 60 min
- 1 min = 60 sec
- 1 grad = 1/400 circle (angle subtended by 1/400 of the circumference of a circle )
- 1 grad = 100 min
- 1 min = 100 sec
- 1 rad = 57˚17’44.8”
Solved sample problems of Introduction to Surveying:
Share: Follow our official Facebook page (@civilengineeringbible) and Twitter page (@CivilEngBible) and do not miss the best civil engineering tools and articles!