Objects of surveying:
The primary object of survey is the preparation of plan estate or buildings roads, railways, pipelines, canals, etc. Or to measure area of field, state, nation.
Object of geodetic surveying is to determine precise positions on the surface of the earth of widely distant points.
Uses of Surveying:
To prepare a topographical map this shows the hills, valley, rivers, villages, town, etc, of a country.
To prepare a cadastral map showing the boundaries of fields houses, and other properties.
To prepare an engineering map to show details like roads, railways, canals, etc.
To prepare military map showing roads and railways, communication with different parts of country.
To prepare contour map and to determine capacity of a reservoirs and ton find the best possible route for roads, railways etc.
To prepare archeological map including places where ancient relics exist.
To prepare a geological map showing areas including underground resources.
Principles of surveying:
There are two fundamental principles.
To work from the whole to the part.
Control points: – triangulation of traversing.
Triangulation divided into large triangle.
Triangles- subdivided in to small triangles
To control and localize minor errors.
On the other hand –It we work from the part of the whole; small errors are magnified & uncontrollable at the end.
To fix the position of new stations by at least two independent process. The stations are fixed from points already fixed by
Linear measurement or
Angular measurements or B
Both the linear and angular measurements.
E.g. Chain surveying- main lines & stations points are checked by means of check or tie lines.