Chapter 4, Problem 4.1P

Define the following leveling terms:

1. vertical control
2. elevation, and
3. vertical datum.

To determine

i.

Definition of vertical control.

Explanation of Solution

Vertical control, also known as basic control or level control is the series of points with known elevation or the benchmarks established on entire area.

The data sheets for vertical control give the

(1) Set of reference points for the station.

(2) Observed or modeled gravity reading at the station, and

(3) Description of the station, its location and juxtaposing details between the stations.

To determine

ii.

Definition of elevation.

Explanation of Solution

Elevation of a point is defined as the vertical distance that is measured along a vertical line with reference to some chosen vertical datum or object, it's also known as the height above the datum or orthometric height. If the elevation of any point is 450 ft, it means the point is 450 ft from the reference datum.

To determine

iii.

Definition of Vertical datum.

Explanation of Solution

Any equipotential or level surface is where the elevations are compared, thereby, calculating every other distance from this surface. This is the surface that is subjectively appointed to an elevation of value zero and is known as reference datum as the points utilizing this datum have heights practically identical to this surface. For example, if the elevation of any point is 450 ft, it means the point is 450 ft distant from the reference datum or vertical datum.