basics of surveying and types very simple

1. surveying

2. Surveying
♣It is the art of determination of horizontal distances,
differences in elevation, directions, angles, locations, areas and
volumes on or near the surface of the earth.
♣ It involves the measurement and recording of the size and
shape (including the vertical shape) of an area on the earth's
surface.

3. The process of survey divided into two parts:
(a) Field work- taking measurements
(b)Office work- computing and drawing

4. Object of survey
♣The primary object of survey is the preparation of plan or
map.
♣The results of surveys when plotted and drawn on paper
constitute a plan.
♣The representation is called a map, if the scale is small. If
the scale is large, it is called a plan.

5. Primary division of surveying
Surveying may be divided into two general classes:
(a) Geodetic surveying
(b)Plane surveying
Geodetic surveying is also called trigonometrical surveying . In this survey, the
curvature of the earth is taken into account, since large distances and areas are
covered.
In plane survey, the earth's surface is considered as a plane. The curvature of
the earth is not taken into account, as the surveys extend only to small
areas.

7. I. Classification based upon the nature of the field of
survey:
(a) Land Surveys.
(b) Marine or Navigation Surveys.
(c) Astronomical Surveys.

8. II. Classification upon the object of survey:
(i) Archaeological surveys.
(ii) Geological Surveys -for determining different strata in the
earth's crust.
(iii) Mine Surveys- for exploring mineral wealth such as gold,
coal, etc.
(iv) Military Surveys- for determining points of strategic
importance both offensive and defensive.

9. III. Classification based upon the methods employed
in survey:
(a) Triangulation Surveys. (b) Traverse Surveys

10. IV. Classification based upon the instrument
employed:
(i) Chain Surveys.
(ii) Theodolite Surveys.
(iii) Tacheometric Surveys.
(iv) Compass Surveys.
(v) Plane Table Surveys.
(vi) Photographic and Aerial Surveys.

11. Uses of survey:
The planning of all engineering and construction projects
extending over large areas, such as highways, railways,
irrigation, water supply etc., are based upon elaborate and
complete surveys.