Calculating excavation volume in multiple levels

[Anonymous]

Hello,

assume we have a topography with 20m depth and sloped edges, 

"Cut" parameter of element returnes total volume of excavation, but i need to know how much excavation is between 0 and 2 m depth, how much between 2 -4 m and so on;

as i figured out, topography elements consist of some mesh geometry, and there is no "Solid" to work with it's faces,

a possible solution is to create multiple virtual building pads, calculate their "Cut" parameter and roll back transaction each time, however, i didn't try this because i am looking for better solutions.

is there any way to accomplish this within revit api? 

[jeremytammik]

Are the volumes convex?

I would just grab the XYZ points and calculate the volume directly from those:

http://thebuildingcoder.typepad.com/blog/2009/06/convex-hull-and-volume-computation.html

[Anonymous]

Dear jeremy,

These excavation are not necessarily convex and may be of variety of shapes - and slop of a single edge may change in elevation. so they don't make any single pyramid,  cylinder or cube but maybe a mixture of them.

So, is there any way to work with these meshes themselft instead of extracting some points from them ( from their traiangles vertices)  to create volume? Using what method revit itself calculates exact Volume of cut and fill between some complicated surfaces?

[jeremytammik]

Search the Revit API help file RevitAPI.chm for "Volume property".

The Solid class has it, and many others besides.

I am sure one of them will fit your needs.

Always do some minimal research yourself before asking others, please.

[Anonymous]

Thank you for your recommendation, but i did more than "minimal" search, not only in .chm but also in api developers guide. i think here is a place to exchange ideas and solutions, i first introduce my own solution and ask others for better ones!

i appreciate your answers but it seems that you didn't read my first  post carefully , i mentioned that there is no "solid" in topography elements, they are "mesh". i am familiar with solid class and its methods and properties and used it several times for elements such as structural framings, floors and walls.

for our information: according to revit api developer guide:

Typically, the objects returned at the top level of the extracted geometry will be one of:

• Solid – a boundary representation made up of faces and edges

• Mesh – a 3D array of triangles

• Curve – a bounded 3D curve

• Point – a visible point datum at a given 3D location

• PolyLine – a series of line segments defined by 3D points

• GeometryInstance – an instance of a geometric element positioned within the element

i think i would use my first solution ,  temporary building pads.

thank you anyways.

[jeremytammik]

Thank you for clarifying the research you did.

That helps a lot, and I was not previously aware of that.

If you have a mesh from the topography element and it represents a volume, you might be able to generate a solid from it using the TessellatedShapeBuilder, and then query the solid for its volume.

Cheers,

Jeremy

[Anonymous]

Thank you for introducing TessellatedShapeBuilder,
however, we need some "face" to create a solid using TessellatedShapeBuilder, and we don't have any faces, just a mesh with its triangles.
as far as i know, we can convert a face to a mesh by using .Triangulate method, but not from mesh to face. it seems logical because every triangle itself is a standalone face and each of them may be in a different plane, so it is not possible to convert a mesh to face.
i think i should give up creating a solid from topography and it seems the only solution is to work with xyz points of triangle vertics as u mentioned.