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Example:

CB

A

 

CB

A

 

CB

A

120  

or 

 S 600 E

 

 

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Angle Types 

  Interior angles

  Angles to the right

  Deflection Angles

Deflection right

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Directions of lines 

Two types of directions:

Bearings 

Bearings are expressed by quadrant with respect to the reference line.

  Measured as the acute angle between the reference line and the lineitself

  Measured either north or south

  Referenced additionally to the east or west

  Referenced to the direction of the survey

Example: Traverse ABC

Line AB –  Bearing =

AC

B

450

 N

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Line BC –  Bearing =

Field process 

Bearings are measured ahead  or forward  and then checked back .

Sta HD Brg AHD Brg BCK Notes

A 121.85 N 62 E S 61 W

B

89.63 S 70 E N 70 W Creek

C

82.61 N 27 E S 28 W

D

A C

B

550

 N

A

D

C

B

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Azimuths 

Azimuths are expressed clockwise with reference to the reference line.

 

Measured as the total angle between the reference line and the lineitself clockwise

  Generally measured from north

   No referencing from the east or west

Example: Traverse ABC

Line AB –  Azimuth =

Line BC –  Azimuth =

AC

B

1350

 N

AC

B

550

 N

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Computing Bearings 

It is quite often necessary to compute bearings from angles

Again, the three requirements for turning an angle:

Example problem: Line AB has been set at S 45

0

 30’ E. Angle B was turned 120

0

 30’.What is the bearing of BC?

AC

B

1200 30’ 

 N

AC

B

 N

S 450 30’ E 

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Computing Azimuths 

Example problem: Line AB has been set at 1340 30’. Angle B was turned 120

0 30’. What

is the azimuth of BC?

AC

B

1200 30’ 

 N

AC

B

 N

1340 30’