Spectra Precision FAST Survey Reference Manual - Manual (Page 255)

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for precise modeling of complex roads.
Stake Slope
The Stake Slope command calculates and stakes out the location of the “catch point” where fill slopes or cut slopes
contact the original ground. The command will also set offset stakes to the catch point and will produce a report of the
slope stake information. The location of the slope stake is dependent on the position of the “pivot” point where the
slope begins and on the slope itself (eg. 2:1, 3:1, 4:1, etc.). Slope stakes are typically used in highway work to locate the
top of slope or top of cut. If design file information is available for the road template and profile, then the slope stake
routine will calculate distance and offset information for all “break points” on the template from the slope stake itself
back to the centerline. This also applies to slope staking conducted by section files, and descriptions associated with the
break points on templates and/or sections are identified by name in the slope stake report.
Note: Slope Staking can be conducted within the Stake Slope command from the fixed "pivot point" of the template,
the end-points of cross sections, or the centerline points of a horizontal and vertical alignment (as for a ditch). Slope
staking, however, can also be conducted directly within the command Stake Road from any picked pivot point on the
template or cross section. One of the advantages of the Stake Slope command is the ability to obtain catch point
information "real-time" using the "non-interval" method of walking parallel to centerline. Stake Slope will also
automatically detect the ditch pivot point in cut scenarios using templates defined by Carlson Civil and Carlson Roads.
Plus Stake Slope knows which side of the centerline you are on and slopes stakes automatically to that side. The main
advantage of Stake Road is the ability to slope stake from any picked point going either Left or Right as specified, for
"staged" or partial roadwork design, or for finding catch points towards the interior of the template (eg. central median).
Stake Road also has a cross section view option (within the Helmut Help). All slope staking is improved if the
instruction to the user is In-Out from centerline and Forward-Back along the axis of the centerline. For this reason, it is
best to set the View Point within FILE, Configure to In-Out and Left-Right, but also click on "Use Centerline for
Reference Object
".
There are “rules” for slope staking. The slope stake is measured from a pivot point, which is user-entered, or starts at
the centerline itself in “point-defined” alignments, or starts at the last template point before the cut or fills when
templates are involved, or starts at the left and right end-points of sections when using section files. Note that in the
command Stake Road (which works with both sections and templates), slope staking can be initiated from any desired
point. This allows for slope staking of interior, central median catch points and slope staking of any side of an eventual
divided highway, being built in stages. Slope staking can be interval based, or accomplished based on where you are
standing right now, independent of station interval.
Although office plans may predict the position of the catch points, slope staking is necessary to accurately determine the
catch points based on actual field conditions. Slope stakes are often set at an offset to the actual catch points, since
stakes at the precise top of slope or bottom of fill are likely to be knocked out by earthmoving activity. Furthermore,
slope stakes are often marked with information on the slopes and distances in toward centerline or in toward the building
pad or other feature. The information on the slope stake is often written in “progressive” form: distance and slope from
offset stake to slope stake, distance and slope from slope stake to outside shoulder, distance and slope from outside
shoulder to edge of pavement, on into centerline. Thus, the slope stake, placed safely beyond the area of construction,
tells the story of the cuts and fills in toward centerline or toward the center of the work.
Catch points for both cut and fill are shown in the typical section graphics below. See these two figures.