Sample COGO Loop Input (Incomplete Alignment Method)

 

Input Code

1 LOCATE 17607 INTERSECT CHA Y8 OFFSET -47.5 CHA CD2 OFFSET 12
2 EQUATE 17609 TO 17607
3 ALI LP1A INC
4 POT 17607 TD N 0 29 59.8 E
5 POT 17608 TL ?
6 SPI LP1AB TL 0 LS 200
7 CUR LP1A TL 0 R 250 M DEF ?
8 SPI LP1AA TL 0 LS 200
9 POT 17609 TL ? TD N 84 13 28.8 E
10 END ALI LP1A
11 S CHA LP1A SPI LP1AB CUR LP1A SPI LP1AA STA 500
12 DES CHA LP1A

Line by Line Code Breakdown

Line 1 Locate point 17607 by intersecting chain -Y8- offset 47.5' left and chain -CD2- offset 12' right.
Line 2 Equate new point 17609 to existing point 17607.
Line 3 Standard Incomplete Alignment Method opening statement with loop name.
Line 4 Starting at point 17607, proceed at a tangent direction parallel to the Collector Distributor chain -CD2-.
Line 5 An arbitrary point 17608 needed to complete the alignment. Let Geopak calculate the tangent length (? = unknown).
Line 6 Back spiral statement with standard naming conventions.
Line 7 Curve statement with unknown minus (left) deflection angle.
Line 8 Ahead spiral statement with standard naming conventions.
Line 9 Proceed to the equated point 17609 with an unknown tangent length paralleling chain -Y8- at that bearing of this point.
Line 10 Standard Incomplete Alignment Method closing statement with optional loop name.
Line 11 Recompile Loop 1A alignment with only spiral curve spiral components beginning at station 5+00.
Line 12 Describe chain to check the alignment.

 
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