Calculating volume from corridor Models

[db16]

Hello,

I've been learning civil3d for some time now and I really want to understand how the program calculates volumes from road corridors.

When the top code is used to create surface from a road corridor, the created surface coincides with the top of the road pavement (binder/wearing course), which is not part of earthworks.

How can I create a surface at the formation level so as to compute actual earthworks?

I hope my question is comprehensible

[Jay_B]

You'll also want to create a "Datum" surface using bottom links, and apply a surface boundary to each surface in Corridor Properties.

This  related thread may also be helpful in understanding "how the program calculates volumes from road corridors."

I'm not familiar with the term "Formation" but the "Datum" is the bottom most layer of your assembly.

[db16]

Thanks,

I'll try your suggestion.

I my region, we call the Datum "Formation Level".

[neilyj666]

When doing this ensure you use the adjustment for bottom links; can't remember the actual wording as not in front of civil now so can't check.

[neilyj666]

...its overhang correction....:)

[MikeEvansUK]

Remember that this won't be (truly) correct on a road with a camber.

The datum surface will follow the surface profile which the sub base or capping does not do, it will slope from one side to another, it also will project past the edge.

This is ok if you want a pinch of salt volume but otherwise I would consider using either generic links or bolting on sub assemblies to form the base layer correctly.

A quick fix would be to use the featureline points instead of links in the corridor surface as this will ignore the crown level projection at the base , it still won't be true tho..

NB based on uk design.