The steps taken by the instrumentman and the
rodman are as follows:
1. The instrumentman determines the center-
line cut by subtracting 350.7 ft from 364.0 ft to
get the cut, or 13.3 ft.
2. The rodman holds at the center line for
a check. The rod should-read 369.3 (the HI) minus
364.0, or 5.3 ft.
3. The instrumentman calls to the rodman,
“Cut 13.3 feet.”
4. The rodman computes
d= 20+(1 x 13.3) = 33.3
as he walks to the left.
5. As he approaches about 30.0 ft from the
center line, he estimates that the ground has a fall
of 4 ft. Therefore, he computes the new cut as
13.3 – 4.0, or 9.3 ft.
This means a new d of
20 + (1 x 9.3) = 29.3 ft.
6. The rodman sets up the rod 29.3 ft from
the center line, as measured by metallic tape.
7. The instrumentman reads 10.1 on the rod
and computes the new cut as
369.3 – (350.7 + 10.1), or 8.5 ft.
NOTE: Here you can also use the grade rod
and ground rod values as explained earlier; the
new cut then will be
18.6 – 10.1 = 8.5 ft.
Refer back to figure 14-36.
8. The instrumentman calls, “Cut 8.5,” to
the rodman.
9. The rodman computes
d = 20 + (1 x 8.5) = 28.5 ft.
He knows, therefore, that 29.3 ft from the center
line is too far out.
10. Figuring that the ground rises about 0.1
ft between 29.3 left and 28.5 left, the rodman
calculates that the more nearly correct cut will be
8.5 + 0.1, or 8.6 ft.
11. By using this cut, the rodman calculates
the new d as
20 + (1 x 8.6),
and sets the rod at 28.6 ft left.
12. The instrumentman reads
and computes the new cut as
369.3 – (350.7 + 10.0) =
10.0 on the rod
8.6 ft.
13. The instrumentman calls, “Cut 8.6,” to
the rodman.
14. The rodman sees that the actual cut of 8.6
ft agrees with his estimated cut of the same, and
calls, “Cut 8.6 at 28.6,” to the instrumentman.
15. The instrumentman checks
d = 20 + (1 x 8.6) = 28.6,
signals the rodman, “Good,” and makes the
following entry into the field book:
16. The rodman marks a stake with 15 + 00 and
C86 and drives it in the ground at 28.6 ft left.
More often, slope stakes may be set by using
a hand level. Their distances out are generally
measured to the nearest half or tenth of a foot.
If a slope stake is placed in an offset position, the
offset distance is also marked on the stake so the
equipment operator is not confused about its
actual location. Slope stakes are seldom used in
areas requiring less than 2 ft of cut or fill.
Curb and Gutter Stakeout
For a thoroughfare that will have a curb and
gutter, these items are usually constructed before
the finish grading is done. The curb constructors
obtain their line and grade from offset hubs like
those described previously. Guided by these, the
earthmovers make the excavation for the curb,
the formsetters set the forms, and the concrete
crew members pour, finish, and cure the curb.
Once the curb has been constructed, shaping
the subgrade to correct subgrade elevation and
laying the pavement to correct finished grade is
simply a matter of measuring down the correct
distance from a cord stretched from the top of
one curb to the top of the curb opposite.
14-40
