Linear Measurements (Chain Survey)
Linear Measurements, 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. Linear Measurement with Chain- On Smooth Level Ground, On Sloping Ground. Errors & Correction in Chaining/ Taping, Type of Error in Chaining, Correction in Chaining & Taping Are Following Type- Correction For Standardisation, Correction for Slope (Cg), Correction for Pull (Tension), Correction for Temperature (Ct), Correction for Sag (Csag), Reduction of length to mean sea level (MSL), Field Work in Chain Surveying- Reconnaissance, Marking of Stations, Running Survey Lines, Taking Offsets. Limiting Length of Offsets- Error only in laying offset, Error in laying direction and liner measurement.
Topics
In plane table surveying we details discuss accessories used in plane table surveying, alidade, tripod, level tube, compass, plumbing fork, setting up the plane table: centering, levelling, orientation, method of plane table survey.
In contour, we details discuss about use of contour, contour interval, properties of contour lines, ridge & valley line, overhanging cliff, vertical cliff. Etc.