Surveying Module 3: Measurement of Distance by Pacing

Measurement of Distance by Pacing

• Measurement of distance is a fundamental operation in plane surveying, requiring accurate determination of the distance between two points on any surface.
• There are eight methods of determining distance: pacing, taping, tachymetric, graphical, mathematical, mechanical, photogrammetric, and electronic distance measurement.

Pacing Method

• Pacing involves counting the number of steps or paces in a required distance to determine approximate distances with low precision.
• A pace is defined as the length of a step in walking, measured from heel to heel or toe to toe.
• A stride is equivalent to two paces or a double step.

Factors Affecting the Length of a Pace

• Speed of pacing affects the length of a pace.
• Roughness of the ground affects the length of a pace.
• Weight of clothing and shoes used affects the length of a pace.
• Fatigue on the part of the pacer affects the length of a pace.
• Slope of the terrain affects the length of a pace.
• Age and sex of the individual affect the length of a pace.

Determining the Pace Factor

• To determine the pace factor, walk along a line with known length on level ground.
• Take at least five trials to determine an accurate value of the average number of paces.
• Divide the known distance by the average number of paces to get the pace factor.
• Pace factor is expressed in meters per pace (m/pace).
• It is essential to walk naturally when determining the pace factor.

Sample Problems

• To determine the pace factor, add the number of paces from each trial and divide by the number of trials.
• To determine the length of a line, multiply the number of paces by the pace factor.