Average elevation for zoning analysis

[Joe-Bouza]

We have to compute the average elevation along the front, sides and rear of a proposed building envelope to calculate the required set back.

Right now I am setting FL with elevation nodes at the required interval, assigning EG elevation and pasting from the panorama to excel to compute the average.

Is there a way I could create a toolbox report to do this? Maybe even from a profile report?

[fcernst]

..But you also need to divide by the number of elevations..

No, you simply divide by the sum of the weights.

[troma]

Sorry, yes, you're right.

[brian.strandberg]

How about this work flow?  It is a little convoluted but it works.

1. Draw a polyline the length of the frontage (make sure this polyline is contained within your surface.

2. Create a block called _point.  The block should just have an autocad point at the insertion point of the block.

3. Use the measure command to insert the _point block at 1 foot intervals.

4. use the _AeccMoveBlocksToSurface to move the inserted point blocks to the surface Elevation.

5. Explode all of the _point blocks.  This will leave you with autocad points at the correct elevation (the point of steps 1-4)

6. Use the CREATEPTCONVERTADESKPTS to convert your point object (at the correct elevation) to Civil 3d points.

7. Export the Civil 3d points to Excel or other spreadsheet program

8. Use excel to compute the average of the exported points.

Convoluted?  Yes, but it does do the job.

Hope this works for you.

[Joe-Bouza]

Good thought but you might want to re-read the OP 😉

[AllenJessup]

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@jfmayo wrote:

A 1' interval in simply insane. I know the town will typically define this standard but 1'? Come on.  🙂

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A Zoning Board, Insane! Come on John. You know better than that!

Allen

[AllenJessup]

Joe,

I like the idea of a mini-Surface. But I can't think of any way to automatically label it or get in in a table. Just copy/paste from the Statistics tab.

Allen

[troma]

There was a post from a different conversation recently about using pipe network structures to get elevations into a table from a surface.

[BrianHailey]

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@fcernst wrote:

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Yup, the n on the bottom should have been a 2.

[fcernst]

The two is up in the numerator.

Every instance of Z1+Z2 has to be divided by two to obtain the average of Z1 and Z2 before their average is multiplied by the specific weight (Li).

[BrianHailey]

I just factored out the 1/2.

[fcernst]

No, you can't just factor out the 1/2...

((Z1+Z2)/2)*L1 + ((Z1+Z2)/2)*L2...../(L1+L2+ ...)

[BrianHailey]

Sure you can.

[fcernst]

Oops..right my bad.

[jmayo-EE]

How are you doing with this? The number of data points is killer and would love to see if ur cooking anthing up over there.

All the towns we work use the 10' interval which I think if from the IBC. With fewer points the Flines and a manually filled out acad table which does all the other req'ed calcs is still faster for us since it is ready to print on the plan without adding processes to go to and from other apps. Here is a very simple example with a town that only uses the front building line in the calc. 

[Joe-Bouza]

Nothing special, but a surface does return the mean elevation so if i create a sall surface from the FL either offset or grading at 0% the average elevation is reported via surface props. I sure wish a surface label property for average elevation was available. Otherwise it doe elliminate the excel feed. Thanks for asking. Howd that thing go for you?