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I have asked this question a couple different times without an efficient response as of yet. I get my bore holes and define my strata. I build my sites and input my site improvements. However, excavation is never directly vertical. How can I define my excavated areas to return original ground at a degree or ratio of slope so that I can get the accurate quantities? A corridor or utility approach do not make sense as these are for large commercial sites that have excavation over 20' below existing grade, then filling up to bottom of foundations. These buildings are not perfect squares or rectangles. It would seem fairly simple to create a side slope feature for over-excavation or site improvements. 

Chase you can either use the

1) create a side slope function and build the shape in the template and tie back into the EG. 

2) use the create surface tie function. You would select the line at the bottom of the excavation, then define the side slope and the surface you want to tie back into.

Let me know if this helps!

Mike, 

The surface tie seems to make the most sense for my purpose. However, after completing the function I do not seem to see the slope visually or understand how the function affects my quantities. The surface created does not seem to tie into my EG layer at all. 

Good morning Chase,

Can you share the TBC file with me?

Michael Tartaglia

Surveyor /Technology Specialists

SITECH Southwest

Cell (480) 390-5310<tel:(480)%20390-5310>

Office( 602) 437-0410<tel:437-0410>

mtartaglia@sitechsw.com<mailto:mtartaglia@sitechsw.com>

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Unfortunately I cannot I am under NDA. Basically I need to overex under several buildings on the same site. I need to go down to the bottom of a peat layer which is as deep as 20 feet in some areas. I need to backfill up to a deep foundation and then again to finished grade. Overexcavation and site improvement modules would not catch a huge quantity of material if I can only take a vertical footprint. If I take the average depth and offset my excavation limits as my site improvement limits, I am not realizing the full depth I need to go to for the bottom of the peat strata layer I  have modeled. 

It would seem that the program has the capability to create surface tie's (which work great for finding the contours of the excavation) and it has the ability to drape site improvements and overexcavation to surfaces. Why not incorporate the surface tie as a slope function within the takeoff portion of the program. Another issue with the surface tie is that the daylight line cannot be used as a surface boundary. So even after I have found the new extent of my dig, I cannot easily and quickly constrain my new surface to this extent. 

In order to get around these issues, I am currently having to create a separate surface for every dig spot, for each surface I am digging through, and having to tie to my existing ground for excavation quantities, and again to the finished design for backfill quantities. Then run a separate surface to surface report for each one. 

Although site improvements are great, the typical section of a building is never vertical. Although surface tie provides the function, it does not help me with my takeoff quantities as integrated currently. 

I use the function a lot as most engineer's don't bother to tie back into existing so I typically have to (especially with building pads).  Make sure you have the surface tie layer turned on; for me that is defaulted to 0 Layer.  You should get something like what is below.   This is a surface tie using a 3D linestring as the reference line, 10' spacing, with a 4:1 cut/fill slope tying to the original surface.  If you are not getting a surface tie, double check that you have an original surface that extends to the location where the tie is being made.  I had this problem once until I realized I didn't give the computer enough information to make the tie (my tie was too flat and was coming up in the neighbor's property ). 

Another helpful thing to do is right click on you Finished Design surface and go to properties.  In the properties pane, turn wire frame to Yes so you can see the surface triangles.  After you create your surface tie, rebuild your Finished surface and TBC will incorporate the tie. You should see triangles formed in the tie as below.  

Then you will have to use Trim Surface Edge command to clean up the perimeter (maybe-most of the time when I use surface tie the edges are clean).  When that is done, run Edge Breakline command on the finished design.  This will create a daylight line at the base of the tie (around the surface) that you can use for the surface boundary.  

I dug around youtube and the help videos but could not find information on how to do this.  It is probably there somewhere but I couldn't find it.  This is how I do it but the wizards at Trimble may have a better way.  Hope this helps.

If you are doing a Takeoff you can also use Add / Remove Surface members to add the new Surface Tie to the Takeoff Surface (OG or FG etc.) before you run the numbers and the Takeoff Report.

If you have to affect the Subgrade Adjusted Surfaces, you may need to run a Surface to Surface Report as you cannot add remove objects to Takeoff Subgrade / Adjusted Surfaces - in that case I build the FG surface, apply Site Improvements to the FG Surface and then use the Create Subgrade Surface command to get the Subgrade Adjusted Surface model. Then I use the Ties to tie out at the slopes that I want and then add the Ties into the Subgrade Surface and then run the Surface to Surface Volume Report to get my Quantities.

If you need a video on this I can try and do one next week. Let me know if this helps.

I also tend to use the Sidelsope command for this as I can add laybacks and offsets in the slopes if needed. 

Thanks

Alan

Alan, 

This is exactly what I am currently doing. 

However, with a master site that includes multiple structures with multiple excavations that need to be done as an overexcavation, and then returned up to finished design at a certain slope. I also do not want my finished design to capture my slopes as they are for foundation excavation. 

It would seem much quicker for the site improvements to have a slope function, so that I can select my bounded area and my improvement creates a FD with subgrade adjusted surface that incorporates that slope, then the takeoff report can have all of the quantities I need. I can then divide them up by areas of interest to break out my quantities. 

The site improvements module seems powerful and increases workflow efficiency substantially, however, not being able to create site improvements that are not strictly vertical seems to not be able to provide a very accurate quantity, and some excavated areas for foundations and other subfloor structures make the use of the corridor module seem burdensome.

Thank you,

Chase

I have not used the landscaping/topsoil site improvement very much, but there seems to be an edge properties feature that seems to represent what I am trying to accomplish. 

Having a site region that can target a slope and not just a specific thickness would be helpful.  I've run into the same problem when doing basements or large crawlspaces where I need the edges to slope up at a 1:1.  

Yes. I work fairly closely with the Trimble dealer up here in Alaska and they have also brought it up as a feature that would be helpful. It seems the functions are in the program, just incorporating them into the site improvements would make site takeoffs substantially quicker. With frost layers up here, our structural section under our building foundations can reach great depths, and with the substantial amount of Peat in the Anchorage bowl, the depths of excavation and backfill are sometimes over 20 feet deep. To not be able to have a slope to tie that back into my finished grade could lose me thousands of yards of material. Especially on the scale of footprints that I am looking at.

Wow 20' of excavation for a building.  The most of I have personally done is 10'.  Anything more than that around here they switch to a structural slab on piers. 

Have fun in Alaska; I would love to visit that state someday.  Meanwhile in Texas its 70 deg F.

That is the foundation type typically used. Structural slab on piers with stem walls and footings. However, the differential settlement on the peat layer is too great. Anywhere there is peat, more often than not we are digging it all out, and in many cases in the Anchorage bowl it can be 20' deep or more. The benefit is that peat is safe almost vertically sloped coming back up, but the load for the building still has to go out to a 1:1. So I am having to model a 1:1 surface tie from bottom of footing down to my bottom of peat layer. Than I can drape that over my finished design for my excavation footprint. If it weren't peat though I would need to create another surface tie from that building load surface tie all the way back to finished grade at the safe slope for whatever soil type i was digging in. This can be a lot of work when all I would really need to do is assign slopes to each site improvement layer or overexcavation and wham. Done.

70 deg sounds nice. It's -15 in Anchorage today. 

It's beautiful in the summer though. Worth the 7 months of hell for the 5 months of splendor.