Slope staking

James Suttles

Active Member
Is there a way to explain what needs to be put into the Javad to do slope staking, I noticed we have a catch point white box, but not sure how best to create the alignment or what I would need to export from CAD to the Javad.

Do we have a manual that would describe the best practice for this? Youtube vid, or something.
 

James Suttles

Active Member
Currently, we are creating a point perpendicular from the centerline at the top or toe of the slope. and also creating a point some distance outside the propose toe or top that is also perpendicular to the centerline. We assign the top or toe elevation to both points and then stake a line between those 2 points until the slope and distance match the desired cut to distance, basically the catch point. Is there a better way to do this, we do not do a tremendous amount of slope staking, it is mostly for the DOT, but when you have several stations to do, it makes more sense to let the LS do the math, and not have to compute it manually.
 

James Suttles

Active Member
Importing a surface is good for general construction staking where contours are available. Most DOT, at least NCDOT, give a set profiles and cross-sections, but no contours. They require slope stakes. So, the question: is there any way to input into the JAVAD the point top/toe of slope along with the slope grade (i.e. 4:1, 2:1) and have it perform the calculation and tell whether to go in our out based on cut or fill?
 

Sdrake14

Active Member
Surface staking does not really function well for slope staking, and comes completely undone once you exit the limits of the designed surface in the reach.

You really need to do it along with alignment staking. I did 4 miles worth in 2017-2018 with Javad but pretty much did the calculation manually at each point while using the alignment function. I created alignments from the plan data on the Jfield then searched kind of traditionally.

I do not see any way that the catch point button can work since I do not find a way to enter the required data. Alignments creating on board is simple enough and you can import a polyline as an alignment, which I have not explored. There is also a way to enter road slope offset info so I assume you will have the Hingepoint available but I find no way to enter the slope out from the HP in the road prism which you would need to calculate the catch.

And from what I see in the LS manual creating the cross sections just blew my fuse and I said no way, easier to create the simple centerline alignment and then search.

A simple routine would be much more usable say that works with alignment staking, where on the fly you enter the current HP offset and elevation along with prism out slope as a "__:1" number, then JFeild could quickly provide the catchpoint data. In, out, cut, etc. Once at the mark if accepted it could provide "offset distance to alignment and offset to hingepoint along with catchpoint elevation which provides what is needed to mark stakes in most situations. Simple One Alignment, 3 entries at each station, 3 outputs.

I am open to suggestions...
 

James Suttles

Active Member
If we could import a CL file from say Carlson, that way we could know what station we are on along the centerline, we could most likely calculate the hinge point in CAD, using the X-sections, from that all we would need would be the calculation of in, out, cut fill, etc. to find the Catch point. If we had a simple routine kinda like stake line, with 2 points, where you tell the CL file, the Station you are wanting to be perpendicular to, and the Hinge point, then the LS could do the math from that point forward.

Let me know if I missed something in that. We get asked to stake slope stakes on roadways, and greenways mostly.
 

James Suttles

Active Member
Here is an example of how we are having to do it now, maybe this helps determine an easy solution, to where the LS can do the math for us.

In the clouded area, there are 3 basic points, PT#2029 is the centerline station @ 16+75, PT#1029.1 is the hinge point for the 4:1 slope, and PT#1029 is located at 90 degrees to the centerline at some arbitrary distance, in this example we used 100' from the centerline, notice the description of 16+75R100. There is a 4th point but its a projection from the radius and is part of the Line for Station 17+75, ignore this point for this example. If you notice the other side of the line has PT#2029.1 and PT#3029, which is the other side of the roadway slope. Same procedure on the other side.

We tell the LS to stake a line between PT#1029.1 and 1029, since both elevations are the same, the cut/fill is computed level between the two points, and as the cut/fill meets the 4:1 slope we can determine the catch point. We have to calculate the catch point by hand. Its great that the LS will stake a line and stake the percentage along the line, but in this instance, that will skew your results. So make sure the points are both at the hinge point elevation.

If the LS could give us an in, out along the line based on the slope and cut/fill, that would simply things.
 

Attachments

  • Slope Stake Example.pdf
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