About Lesson
Key Terms in Chain Surveying
- Survey Stations
- Main stations: Endpoints of main lines (outline the survey area).
- Subsidiary/Tie stations: Points on main lines to locate internal details.
- Base Line
- Longest and most important chain line.
- Must be measured with high accuracy.
- Tie Lines
- Used to locate features far from the main line.
- Check Lines (Proof Lines)
- Help verify accuracy of measurement and plotting.
- Offsets
- Lateral measurements from objects to the chain line.
- Perpendicular offset: At 90° to the chain line.
- Oblique offset: At an angle (when 90° not feasible).