How do you do it? I recently had to come up with a quick answer where we were revising some grades. The engineering plan didn't ACTUALLY work with the existing conditions. We had to elevate some portions of the proposed parking lot by 0.5' or 0.25' depending on the location. I just did a quick area and multiplied by that value then divide by 27 to get cubic yards (CY).
Then I did a more detailed analysis - I made sure to preserve my old point file based on the stakeout for the original grades. I generated a surface from those and then one from the newly calculated grades. Via Civil 3D I derived the volume between the two surfaces. The numbers don't exactly match up, so I think we ordered a little extra material. (It is a small job, and this wont be a problem. We'll just raise the high points a little and grade down from there). Just wondering what other methods there are for quick calcs before resorting to computerized stuff. Anybody got any good tricks?
That's pretty much how I would have done it. Only difference is with the detailed analysis, I would have used Carlson, because that is what I have.
I do it the same way you did. Sometimes I'll check a few spot el's in the middle of the proposed changed gradings to have a few different heights to calc from. That's basically what civil 3d is doing but interpolated for thousands of points.
I believe some data collectors have the ability to create surfaces and calc volumes but not ours.
You could use contours as well to determine volumes, but your method seems to have been the quickest.
No matter what, it is always an estimate due to loose yardage vs. in-place. Many times, the contractors are using truck counts anyway.
I sometimes create points from the design surface for layout (if I have it and if it's done properly), but I've always just staked points.
Do you guys actually use the surface model imported into the data collector? I know this capability has been around a long time, but nobody I worked with was ever that forward thinking. I think for a large earthwork site it would be hugely beneficial to have the information in the collector this way.
I'm always being asked "what's the grade supposed to be right here or over there?" It would be nice to instantly have the answer anywhere on the job. I've always done it the other way just by creating grade points. Obviously you'd have to keep verifying that the surface model was correct and to whatever level of detail you need.
For most airport/roadway projects, I enter the design and have the ability to check grade anywhere I set my rod down.
For large grading operations (landfills and parking lots), I usually load the surface model up to check grade prior to approving it for paving.
I do navigate to the grade breaks, where you would normally stake specific points.
Dan Patterson, post: 333371, member: 1179 wrote: I sometimes create points from the design surface for layout (if I have it and if it's done properly), but I've always just staked points.
Do you guys actually use the surface model imported into the data collector? I know this capability has been around a long time, but nobody I worked with was ever that forward thinking. I think for a large earthwork site it would be hugely beneficial to have the information in the collector this way.
I'm always being asked "what's the grade supposed to be right here or over there?" It would be nice to instantly have the answer anywhere on the job. I've always done it the other way just by creating grade points. Obviously you'd have to keep verifying that the surface model was correct and to whatever level of detail you need.
Um... yeah, we been in the 21st century for a while now. 😛
I have my design drawing in my Carlson Surveyor+. I can pick points on it just as easy as on my laptop. New drainage scheme? No problemo!
There is no end to the rabbits you can pull out of your hat right there in front of the contractor. B-)
P.S. I would do it the same as you. A little extra is cool. If you short it they will remember THAT forever.:stakeout:
Dan Patterson, post: 333345, member: 1179 wrote: How do you do it? I recently had to come up with a quick answer where we were revising some grades. The engineering plan didn't ACTUALLY work with the existing conditions. We had to elevate some portions of the proposed parking lot by 0.5' or 0.25' depending on the location. I just did a quick area and multiplied by that value then divide by 27 to get cubic yards (CY).
Then I did a more detailed analysis - I made sure to preserve my old point file based on the stakeout for the original grades. I generated a surface from those and then one from the newly calculated grades. Via Civil 3D I derived the volume between the two surfaces. The numbers don't exactly match up, so I think we ordered a little extra material. (It is a small job, and this wont be a problem. We'll just raise the high points a little and grade down from there). Just wondering what other methods there are for quick calcs before resorting to computerized stuff. Anybody got any good tricks?
Hello Dan,
TBC creates a good 3d model depending on the surveyor, it also has volume reports calculating mounds and depressions....works the same as cad by declaring a datum but is less cumbersome and gives quicker results....used it alot in the mine to calculate materials coming in and going out....best of luck
Just a bit of grave digging... ( sorry for replying to old post )
I dont know how complex your original set out file was.
TSC3:
Select all original points on map --> create surface
Pickup/Key in new points, select all points ( replacing the altered points of course) on map --> create surface
Cogo --> compute volumes --> surface1 to surface2
Only thing tricky with this is it cant seem to define a boundary
Did the computer factor in fluff and compaction? With the sand we usually have, we generally use 1.25 and 0.9 for multipliers.