what is the best way to get accurate cut/fills

[Justin Marchiel]

I have a site that slopes with a bank that is about 30 deg from true east west. we are placing our building in the back but orientated true east west. as you could imagine the building will be more in the bank on one side and less on the other. we are going to cut the bank on 1 side and fill the other. my questions is how do i grade my site, and what to do about pads. i want to get some accurate cut fills so that we know we are not having to truck or haul in too much material.

Where i get confused is where do i grade my new topo to? do i grade it as if we are filling 100% under the building, then the pad will subtract the right amount, or do i grade to the outside face of the building and not use a pad at all?

I have no good way to test actual quanties as the bank is irregular and i am kind of left out in the dark.

Thanks

[Dimitri Harvalias]

In order to calculate cut and fill Revit needs to compare an original to a revised copy o your site.

You need to move your topo to an existing phase and create a copy of your original site topo in the new phase. You can then create a graded region within the new topo and the relative cut and fill will show up as part of the topo properties. You can also schedule these values. If you just select the graded region tool on the site tab of the design bar the instructions will point you int he right direction. (Make sure you check the Copy Internal Points option)

Check out the help file and the tutorials on graded regions, phasing and cut and fill. If you're still stuck send another post.

[Justin Marchiel]

I understand that part, it just am not sure how to handle the info under the building. do i grade so that the site surface extends at the floor level under the entire building then use a pad to subtract it, or do i grade my new region so that it drops at the building foot print.

I ended up doing it the second way and not worrying about the pads. It seems that i will then get the cut/fill by just looking at the surfaces, and not have to worry about the pads. it also seems that modeling it this way is more like how it will be "built" in the field.

Justin

[Alex Page]

bear in mind that here in NZ the 'fill' soil quality of the 'fill' is generally different than the soil quality of the 'cut', therefore we dont do a net cut/fill total anymore - it really caught us out badly since on one of our jobs the builder quoted on only removing the net cut/fill, whereas he needed to allow to remove all the cut soil and get in new soil.
It was a very hard site too access, and he had allowed to take out ~3 c.meters, whereas he took out ~9 c.meters and had to helicopter in ~6 c.meters. Our client was not impressed!

[SkiSouth]

Another note is that fill takes about 20 percent more in actuality due to compaction requirements. So while there is a net calculation, there is a loss of "fill" due to compaction. Don't ask me why, that's just what my earthwork subs tell me. So if you are scheduling, put a disclaimer of some type that this is a volume calculation, and not the actual quantity required.

[gordolake]

Another note is that fill takes about 20 percent more in actuality due to compaction requirements. So while there is a net calculation, there is a loss of "fill" due to compaction.
As material is dug out it bulks up (20%) and the reverse is true when filling from truck /stockpile compaction is needed, therefore bulking factor should be applied.

Also allow in quantities for removal and respread of topsoil as it cannot be used as fill material and can vary in depth over the site.

steve