Surveying Notes

Surveying Dulance Correction 1. Incorrect Tape Length Case 1 If standard length of the tape (1) is the rame with your actual length of the tape (1) error O Care 2 If the is too short e=1-L; e=(-) -negative emc Care 3 If the is too long add the ener TD MD+E where true distance MD measured dirtance E= total error 2. Temperature Correction *Tapes are mandaraized at 20°C. If temp. increaver, expands. If temp decreases, contract GALAT AL (T2-T1) G : Correction due to temp. 11-GX10 m/me For steel only L Standard length of the tape AT Change in temperature Lp 72 Temp. auring time of observation Ti Standard temp/temp during calibration Pull Correction Standard Tension of steel lape 4kg-55kg = 10 165-12 lbr Unit Weight of fieel Tape 7.866x10 kg/cm³ 490 lbs/113 Formula for correction: APL (P2P) L CP A AE where, Cp Correction due to pull P2 Applied Pull P. Standard Pull/Pull applied during calibration A Cross section area of tape E Modulus of Elarticity 200 690 Sag and Tepcion Correction Formula Crag 24 Pe where, P2 Applied pull w linear den aty (kg/m) *meter or millimeter ang unit Normal Tenviin Crag Cpull *This will identify the correct pull to compenvale the correction due to rag (Creg) Slope Correction Gentle Slope less than 201 h Criope 25 Steep vioper 20%-30% Cutope Very Steep sloper greater than 30% H= vara Crimpe S-Score (1-core) where h diff in elevation. Crepe correction Sloang distance H Horizontal distance A H(5) 1(5) + h 1 1 =H-Criope H= S + Crlope Mean Sea Level Correction * Correction is SUBTRACTED if teOVE VEA LEVEL *Correction is ADDED If BELON VEA LEVEL Formula R where, L'OMS) length of mean sea level. L length mearured R= Distance from the earth's core To the specified location. (& Reavish th) Rearth Distance from the earth's core to the mean sea level h= elevation of the place where the length is measured.