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 measurement of area and volume, we details discuss about mid ordinate rule, average offset rule, trapezoidal rule, simpson's rule for measurement of area & trapezoidal rule / end area method, prismoidal / simpson’s rule for measurement of volume.
In equipment used in chain surveying,we details discuss about surveying chain, types of chain- revenue chain, gunter’s chain, engineer’s chain, metric chain, suitability of chain, unsuitability of chain, units of measurement, tapes-cloth or linen tape, metallic tape, steel tape, invar tape, pegs, arrows, ranging rods, offset rods, plumb bob, clinometer, cross-staff, optical square, prism square, chain survey instruments, distance measuring device, instruments used for various types of measurement