27.1
Adjusting a Traverse
Consider that a traverse with four sides is plotted based on the field measurements taken during a site survey.
First, the internal angles of the traverse are calculated and summed, yielding 359 degrees and 48 minutes.
To achieve an accurate four-sided traverse, the sum of the internal angles must be 360 degrees. The shortfall of 12 minutes indicates an error in recording or measuring the readings during the fieldwork.
To correct this error and ensure accuracy, the discrepancy is adjusted by distributing the 12-minute error equally among all four internal angles of the traverse, resulting in an addition of three minutes to each angle.
After adjustment, the summation of the corrected angles equals 360 degrees, which confirms the accuracy of the correction.
Finally, the magnetic bearing for side AB is obtained on the field as the starting point, and the new bearings for the remaining sides are calculated using the corrected internal angles as references.
In the site survey of a four-sided traverse, internal angles are essential to ensure geometric accuracy. The survey revealed that the sum of the measured internal angles was 359 degrees and 48 minutes, which is 12 minutes less than the expected 360 degrees. This discrepancy signals an error likely arising from measurement inaccuracies during the fieldwork.
To rectify this error, the adjustment process involved distributing the 12-minute shortfall equally across the four internal angles. By adding three minutes to each angle, the corrected values were recalculated. The adjusted sum confirmed the accuracy of the traverse with a total of 360 degrees, ensuring that the traverse conforms to geometric principles.
Following this correction, the bearings of the traverse sides were computed. The magnetic bearing of side AB was used as the reference starting point. Using the corrected internal angles, the bearings for the remaining sides were systematically determined. This process ensures that the angular and linear relationships between all sides are accurately aligned, which is critical for precise plotting and mapping.
This method rectifies potential errors and highlights the importance of careful measurement and error adjustment in field surveys, reinforcing the accuracy and reliability of the resulting data.
Consider that a traverse with four sides is plotted based on the field measurements taken during a site survey.
First, the internal angles of the traverse are calculated and summed, yielding 359 degrees and 48 minutes.
To achieve an accurate four-sided traverse, the sum of the internal angles must be 360 degrees. The shortfall of 12 minutes indicates an error in recording or measuring the readings during the fieldwork.
To correct this error and ensure accuracy, the discrepancy is adjusted by distributing the 12-minute error equally among all four internal angles of the traverse, resulting in an addition of three minutes to each angle.
After adjustment, the summation of the corrected angles equals 360 degrees, which confirms the accuracy of the correction.
Finally, the magnetic bearing for side AB is obtained on the field as the starting point, and the new bearings for the remaining sides are calculated using the corrected internal angles as references.
- Four-sided Traverse - A survey method where a parcel of land is divided into four sections.
- Internal Angles - Internal joints between two adjacent lines.
- Measurement Inaccuracies - Errors due to equipment or human miscalculations.
- Adjustment Process - Rectifying measured discrepancies to ensure data accuracy.
- Bearings - Angle at which a line is oriented and measured in clockwise direction.
- Define Four-sided Traverse – Explain it as a survey method of dividing land (e.g., Four-sided Traverse).
- Contrast Internal Angles vs Bearings – Explain key differences (e.g., alignment vs orientation).
- Explore Examples of Measurement Inaccuracies – Describe a scenario where angles are inaccurately measured (e.g., misread instrument).
- Explain Adjustment Process – Short description of how errors are corrected.
- Apply in Context - How bearing corrections can impact overall accuracy of the survey.
- [Question 1] What is a four-sided traverse and how are its internal angles measured?
- [Question 2] What could cause measurement inaccuracies in a survey?
- [Question 3] How does the adjustment process correct errors?
From Chapter 27:
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27.1 : Adjusting a Traverse
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