Horizontal distance measurement on plain ground

  • Horizontal distance means the distance between two points measured at a zero percent slope.

  • For measuring horizontal distances, there are various methods used

  • The various methods along with their accuracy are as follows:

 

S.No. 

Method 

Accuracy

1. 

Pacing

 \( \frac{1}{100} \)

2.

Tacheometry

 \( \frac{1}{500} \)

3. 

Taping

 \( \frac{1}{5000} \)

4. 

Electronic Distance Measurement (EDM)

 \( \frac{1}{1000000} \)

 

Steps for Pacing

  • Pacing is the process of walking a certain distance and counting the number of steps (paces) to cover the distance.

  • Pace factor is calculated by walking a measured distance and determining the average length of paces (steps).

  • Take a measuring tape and two pegs.

  • Fix the pegs on the ground at two points 20m apart from each other.

  • Start walking from peg A to peg B and return to peg A and then again to peg B.

  • Continue the process five times to give the value of number of paces, say P1, P2, P3, P4, P5 for the length AB.

  • Now pace factor is calculated as follows:

Average number of steps, \( \bar{X}= \frac{P1+P2+P3+P4+P5}{5} \)

And pace factor, PF=\( \frac{20 m}{ \bar{X}} \)

Steps for taping

  • Taping works by applying a known length of tape to a line.

  • Select two points on the ground (A & B).

  • Measure the distance from point A to B using a 50m tape.

  • Remeasure from point B to A.

  • The more the measurement, the accurate is the result.

  • Horizontal distance is calculated by adding all the results and dividing by the number of measurements.

Last modified: Wednesday, 29 May 2024, 11:48 AM