Trigonometric Levelling & Tacheometry
Tacheometry, Instrument Used In Tacheometry – Tacheometer, Stadia Rod. Different Systems of Tacheometric Measurement- Stadia System (Fixed hair system, Movable hair system), Tangential System, Subtense Bar System, Theory of Tacheometer, Distance and Elevation Through Tacheometer- When a Staff Is Vertical, & When a Staff Is Perpendicular to Line of Sight.
Topics
In trigonometric levelling, we details discuss about trigonometric levelling, determination of elevation of object when its base are accessible & not accessible & when the two instruments are not in the same vertical plane.
In liner measurements,we details discuss about procedure in chain surveying,basic definition of chain surveying- main station, tie station, main survey line, tie line/ subsidiary line, base line, check line/ proof line, offset, chainage, well conditioned triangle.Correction in chaining,limiting length of offsets.