Calculating Volumes between 2 elevations

[martin888888]

We have a good size channel and the section for the channel varies quite a bit.  We want to find the volume excavated in the channel between 2 elevations (it is the area of sand per the goetech report), see attached.  Is there an easy way to do this?  A template was not used to create the channel surface, breaklines and gradings were used.

[neilyj666]

I presume that the sand is between 300 and 310 but that the channel section varies in level along the channel?

[martin888888]

Thanks for responding. Yes, the sand elevation is between 300 and 310. And the channel section varies quite a bit along the alignment. We have 7 different cross sections and the bottom does vary in elevation.

What I did was cut a bunch of sections and just get an estimate that way but there has to be a better way to do this.

[neilyj666]

A bit busy to look at this in any detail and I'm not sure its a one step calculation but two thoughts

1. Would the stage storage options work for you - I'm not sure how this works so can't offer any more on this method.

2. Could you create a hybrid channel defined by the 300 and 310 contours or create two planes at 300 and 310 and then calculate the volumes?

[fcernst]

Use a Corridor.

300 = Datum surface, 310 = FG surface and compute volumes. Use flat daylight slopes or extract the 300 and 310 contours to be used as outer Targets.

[NMRollo]

Create plane surfaces that extend beyound your channel at elevation 310 and 300.

Paste FG surface to 310 surface (FG/310 compiled)

Create TIN volume surface  with the FG/310 compiled as the base surface and the 300 plane as the comparison surface

Voila.

EDIT: ALL WRONG. SEE NEXT POST

[NMRollo]

Sorry Martin. I messed that up.

Try this.

Create plane surfaces as previously suggested.

Create TIN volume surface "1" from FG and 310

Create TIN volume surface "2" from FG and 300

Volume of sand = Volume from "1" - Volume from "2"

[troma · Accepted solution]

I think this is the easiest way. But be careful; don't look at the NET volume. You only want to look at the FILL from FG to 310, and the FILL from FG to 300. The CUT represents the area where the 'plane surface' is below FG (i.e. extended out further than necessary) and should be ignored.

[fcernst]

Typically on longitudinal projects like channels and roads, the team wants to see volume info per station. Like this:

[martin888888]

Thank You - That worked great.

[faisal.hamdan]

Iwant to how can I calculate volume between 2 surfaces