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This document provides formulas and procedures for trigonometric leveling, traversing, and calculating the areas of polygons using double meridian distance and double parallel distance methods. It defines key terms like horizontal distance, radius of earth's curvature, elevation, bearing, azimuth, interior angles, exterior angles, and deflection angles. Formulas are given for calculating the correction due to curvature and refraction based on horizontal distance and earth's radius. Procedures are outlined for traversing, correcting traverse measurements, calculating omitted measurements, and computing total area using double meridian distance or double parallel distance.
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0% found this document useful (0 votes)
746 views1 page

Surveys

This document provides formulas and procedures for trigonometric leveling, traversing, and calculating the areas of polygons using double meridian distance and double parallel distance methods. It defines key terms like horizontal distance, radius of earth's curvature, elevation, bearing, azimuth, interior angles, exterior angles, and deflection angles. Formulas are given for calculating the correction due to curvature and refraction based on horizontal distance and earth's radius. Procedures are outlined for traversing, correcting traverse measurements, calculating omitted measurements, and computing total area using double meridian distance or double parallel distance.
Copyright
© © All Rights Reserved
We take content rights seriously. If you suspect this is your content, claim it here.
Available Formats
Download as DOCX, PDF, TXT or read online on Scribd
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TRIGONOMETRIC LEVELING TRAVERSE (CALTECH)

hcr correction due to curvature and refraction INPUT MODE [2] (CMPLX) RESULTS
k horizontal distance TRAVERSE
A fr. N w/ sign a + b SHIFT [2][3] r
R radius of earths curvature
L; NE L L
Derived Formula L; NW L(360 ) L
For R = 6400 km Lat + Dep LA fr. N
L; SE L(180 ) (L )
m hcr = 0.067k2 km L; SW L(180 + ) (L)
L:Length of Course Azimuth from North: Bearing STORE Every Traverse in Every Letter (A-F)
For R = 6350 km :Bearing clockwise from North (+)clockwise
m hcr = 0.0675k2 km ()counter cw NOTE: Abs(LA fr. N) = L
All
arg(LA fr. N) = A fr. N
General Formula (+)from North
()from South
6 k2
km hcr = ( ) km
7 2R
Latitude, Departure, Linear Error of Closure
LA fr. N (using the table) = ( Lat) + ( Dep)
Principles khor
klevel hcr ( Lat) + ( Dep) SHIFT [2][3] r LECLEC
1) khorizontal = klevel
2) k y1 and k y2 R Corrected Latitude and Departure
R
Elevation Compass Rule
A L
el. A = el. ins. +hcr + y1 LA fr. N course
L
[( Lat) + ( Dep)] = Corr. Lat + Corr. Dep
y1
y1 = k tan k Transit Rule
|Latcourse |
hcr LA fr. N |Lat| [( Lat) + ( Dep)] = Corr. Lat + b
el. B = el. ins. +hcr y2 y2 |Depcourse |
LA fr. N [( Lat) + ( Dep)] = a + Corr. Dep
y2 = k tan B |Dep|

Corrected Length, Bearing/Azimuth from North


Corr. Lat + Corr. Dep SHIFT [2][3] r Corr. LCorr. A
TRAVERSE (Angular Measurement) (+)clockwise
SHIFT [2][1] arg[Corr. LCorr. A] = Corr. A Corr. fr. N ()counter cw
Interior Angle (Closed Traverse) Corr. fr. S = 180 Corr. fr. N
= 180(n 2) Omitted Measurement (One Traverse Unknown)
Exterior Angle (Closed Traverse) L = LA fr. N
(+)clockwise
= 180(n + 2) SHIFT [2][1] arg[LA fr. N] = A fr. N fr. N ()counter cw
fr. S = 180 fr. N
Angle To The Right
Clockwise
Angle To The Left
Counter Clockwise AREA BY DOUBLE MERIDIAN DISTANCE
Deflection Angle AND DOUBLE PARALLEL DISTANCE
= 360 (Closed Traverse) BY DMD
+
+, R, Right: Clockwise DMDfirst = Depfirst Lat Dep DMD 2A

, L, Left: Counter Clockwise DMDnext = DMDfirst + Depfirst + Depnext Lat1 Dep1DMD1 2A1


Bearing DMDlast = Deplast Lat2 Dep2 DMD2 2A2
MODE [3][2]
NE, NW, SE, SW 2Acourse = DMD Lat x for DMD

Due North, Due East, Due West, Due South 1 y for Lat Lat n DepnDMDn 2An

Atotal = | 2Acourse | SHIFT [1][3][5]
If AB : NE then AB : SW 2 1
A total = 2 | xy|
AB = BA NW
Azimuth BY DPD
Dep Lat DPD 2A
Clockwise from N (Land) DPDfirst = Lat first
Dep1 Lat1DPD1 2A1
Clockwise from S (Navigation) DPDnext = DPDfirst + Lat first + Lat next

A fr. N Dep2 Lat 2 DPD2 2A2
A 180 = A A fr. S DPDlast = Lat last MODE [3][2]
2Acourse = DPD Dep x for DPD
1 y for Dep Depn Lat nDPDn 2An
Atotal = | 2Acourse | SHIFT [1][3][5]
TRAVERSE (Linear Measurement) 2 1
A total = 2 | xy|


Lat

OMITTED MEASUREMENTS
Dep SIMPLE CURVES
Latitude Departure Radius of Curvature
Lat = L cos Dep = L sin Arc Basis (20m arc) 20 m LC

1145.916 20 RI
180
Rec(L, ) = Lat, Dep R= D
D
= I R D
R I

Traverse Length Bearing Chord Basis (20m chord)


20 m 10 m
Dep 10 20/2 D
L = Lat 2 + Dep 2 tan = | | R= D = sin ( 2 ) D
sin( ) R R R
Lat 2
D 2

Pol(Lat, Dep) = L, Length of Curve


RI PI I
Sign Convention (After Using Formula) LC = RIrad = 180
T T
Lat: N + S Tangent Distance LC E
I
Dep: E + W T = R tan 2 PC M PT
Long Chord Distance C
I
CLOSED TRAVERSE C = 2R sin 2
R R
Lat = 0 Dep = 0 Middle Ordinate I
I
M = R (1 cos 2)
Disclosure PI: point of intersection
Lat 0 Latitude Disclosure External Distance PC: point of curvature
I
Dep 0 Departure Disclosure E = R (sec 2 1) PT: point of tangency

Linear Error of Closure Deflection Angle of a Point on the Curve


a
=2
LEC = ( Lat)2 + ( Dep)2
a
tan = b
Relative Precision b R
LEC Ra
RP = cos = R
Perimeter PC Ra
Station
BALANCING THE TRAVERSE Sta. PC = Sta. PI T
Sta. PT = Sta. PC LC
Adjustment (with sign convention)
Corr. Lat = Prelim. Lat CLat COMPOUND CURVES
Corr. Dep = Prelim. Dep CDep REVERSE CURVES
Compass Rule
L
course
CLat = Lat Perimeter
Lcourse
CDep = Dep Perimeter

Transit Rule
|Lat|course
CLat = Lat |Lat|
|Dep| course
CDep = Dep |Dep|

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