Corridor Volume Concepts

[mabbas]

I am new to C3D corridors and need some help with a functionality concept.

I have a simple alignment (10 elements, 5 curves), an existing surface model from survey data, a proposed profile with 5 elements, 2 vertical curves, and a basic assembly (BasicLane and BasicSideSlopeCutDitch both sides).

Is there a way to produce average end area volumes from this WITHOUT creating a surface model from the corridor model?  I can open the Corridor Section Editor and view my cross sections, so it seems that all the necessary information is present to do this.  What am I missing on this?

[Jay_B]

The surfaces are required for corridor volume calculations.

Start by reading the help for Calculating Earthwork Volumes from Corridor Models.

[mabbas]

I am stunned that C3D cannot do this without a corridor surface model.  Then does it really provide true average end area volumes?  Does it use the corridor surface model to prepare average end areas or does it use the cross section geometry?

[Jay_B · Accepted solution]

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@MehwashAbbas-WPM wrote:

Then does it really provide true average end area volumes? 

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AFAIK Yes, it uses the average end area method where the Datum surface is compared to the EG surface to obtain cut / fill excavation quantities based on your corridor frequency interval and companion sample lines at the desired interval based on the corridor from daylight left to daylight right.

There's another option I'm aware of, creating a Tin Volume Surface surface which will compare 2 surfaces.

[mabbas]

Thanks, this is what I needed.

I follow the reasoning on the end areas.  Since the corridor TIN is created from the defined intervals, it wouild stand to reason that the triangle vertices would correspond to the geometry at the given intervals.  I will confirm this for my own piece of mind.

[fcernst]

 Then does it really provide true average end area volumes?

When you compute the materials for a sample line group, you can use three different volume calculation methods: Average End Area, Prismoidal, or Composite.