Add an interface with IFC structural analysis model.

[lcpt]

The IfcStructuralAnalysisModel is used to assemble all information needed to represent a structural analysis model. It encompasses certain general properties (such as analysis type), references to all contained structural members, structural supports or connecting members, the connection properties, as well as loads and the respective load results.

For a general description of BIM implications in structural analysis see: http://projekter.aau.dk/projekter/files/32688467/structural-modelling-and-analysis-using-bim-tools.pdf

Form a description of the IFC structural analysis model see: http://www.buildingsmart-tech.org/ifc/IFC2x3/TC1/html/ifcstructuralanalysisdomain/lexical/ifcstructuralanalysismodel.htm

[berndhahnebach]

I have collected some informations and a few example files in this regard on https://github.com/berndhahnebach/Ifc_StructuralAnalysisView .

Have you started some development in this regard already?

[anaiortega]

These articles deal with several verification tests included in the verif directory, but not exactly a tutorial: - Interaction diagrams (tests: test_diag_interaccion01.py to test_diag_interaccion06.py, interaction_diagram_mayavi.py) http://www.xcengineering.xyz/blog_doc/2016_interact_diag/interactionDiagram.pdf - Tension stiffening (tests: test_concrete02_02, test_smearedCracking_01.py to test_smearedCracking_06.py) http://www.xcengineering.xyz/blog_doc/2017_tens_stiff/XCtensionStiffening.pdf - Building according to Eurocode (https://github.com/anaiortega/XCmodels/tree/master/buildingEC2 , probably outdated) http://www.xcengineering.xyz/blog_doc/2017_EC2building/EC2Building.pdf - Vibrating string (test: test_string_under_tension.py) http://www.xcengineering.xyz/blog_doc/2017_vibr_string/modes_vibrating_string_tension.pdf - Prestressing (tests: test_layout3D_frictLoss_prestress_tendon.py, test_anchorageLoss_prestress_tendon_01.py, test_loss_prestress_units_01.py, test_anchorageLoss_prestress_tendon_03.py, test_layout2D_frictLoss_prestress_tendon.py, test_anchorageLoss_prestress_tendon_04.py, test_anchorageLoss_prestress_tendon_02.py, prestressed_concrete_section_02.py, prestressed_concrete_section_01.py) http://www.xcengineering.xyz/blog_doc//2018_prestressing_partI/XC_prestressing.pdf - Tensegrity (https://github.com/anaiortega/XCmodels/tree/master/tensegrity_prisms) http://www.xcengineering.xyz/blog_doc/2017_tensegrity/XC_tensegrity_models.pdf

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On 03/10/18 07:44, Bernd Hahnebach wrote: I have collected some informations and a few example files in this regard on https://github.com/berndhahnebach/Ifc_StructuralAnalysisView . Have you started some development in this regard already? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#22 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AMRucQ-baiFTTecCLp8Key8R3757_fCuks5uhE7UgaJpZM4H0nU0>.

-- Ana Ortega /Structural engineer (ICCP) / www.xcengineering.xyz <http://www.xcengineering.xyz>

[berndhahnebach]

Ana you may posted this in the wrong issue. This is about ifc structural analysis view.

Have you done any development in the regard of ifc structural analysis view already? I may have an interesting project in this regard where xc could be very very useful.

bernd

[lcpt]

We have talked a lot, but we have not done anything yet.

We are very interested, but we thought that we'll need to extend the collaborator network to develop that.

Luis.

[berndhahnebach]

What where your conclusions? Develop an importer in C++ based on one of the opensource libraries around (for example ifcquery or ifcopenshell) or develop in Python based on IfcOpenShell or something totaly different?

As I have written, I'm involved in a project we gone try to do a proof of concept (POC) ot parametrically connect geometry to analysis. I will get mid faces and lines and load faces. The idea ist to connect this with XC. Thus I'm really interested in XC from project point of view ATM. The idea was to tranfer geometry with IFC structural analysis view. I have some experience with the IfcOpenShell Python API since Iuse the API inside FreeCAD quite a lot.

BTW: Personally I'm interested in the whole project XC, since it is a structural analysis software not for university but for engineers like me too :-) and of course because it uses Python and Python is just great!
BTW2: Since our software at work AxisVM exports to ifc structural analysis view it would be possible than to transfer geometry easily to XC and to get more used to work with XC.

bernd

[anaiortega]

As Luis wrote, we have not done any IFC development. The conversations he refers to date back a few months ago, when we were contacted by a software company that kindly invited us to include XC in a BIM server so that the program would gain in visibility.
https://bimserver.center/bim_store.asp?lang=0
Obviously, for that, it seemed vital to implement a good BIM import / export in XC. At that time we thought that the path to take was to make use of the development that had already been done for freeCAD.
Unfortunately, later we have been developing other capabilities that were more urgent for the work, so the time we have dedicated to the ifc is almost zero, it can be said that we are a little green on these issues.

I think, therefore, that it would be up to you to lead the project you are talking about and tell us where you would need our help.

Ana

[berndhahnebach]

thanks for the information. OK I may give it a try. But it will be in Python based on IfcOpenShell.

ATM I'm sturggeling to understand the geometry definition of XC ... https://github.com/anaiortega/XCmodels/blob/master/workingModel/model_gen.py#L26-L174 and to get some data out of XC see #33 (ATM my main interest is geometry or if this is not possible the mesh.)

bernd

[berndhahnebach]

I have remodeled workingExample in another structural analysis software, to be able play with ifc, but I even do not know if the geometry I have taken from model_gen of workingModel is the right one?

geometry solid

geometry FEM

with dimension

[anaiortega]

It seems to me it's OK.

About your previous question (geometry definition in workingmodel script):

In XC you can do direct generation of the mesh (nodes, elements, ...) or generate geometry (points, lines, surfaces, volumes, ...) and mesh automatically.

The way it's done in the workingmodel script is the second one, but using some functions that camouflage a little the geometry generation. It's constructed by making a grid of hot points (defined by coordinates in lists xList, yList, zList) that we are going to use lately to generate lines, surfaces , ... The way we will refer to one of this points is by calling the index (i,j,k) that its (x,y,z) coordinates occupy in those lists. Sets of points are also selected by defining a range of index ((i_min,j_mim,k_min),(i_max,j_max,k_max)) that point to their ((x_min,y_mim,z_min),(x_max,y_max,z_max)) coordinates.

It is just one way to do it, the user can choose the one that suits him best. In any case, ideally you should group the entities in sets that contain geometric stuff (surfaces, lines, points) and its attached nodes and elements. In this script we have many of them: beamX, beamY, columnZ, foot, wall, decks, ...

You can have access to those elements by iterating in the corresponding get method. For example:
listOfSurfacesInSetDecks=[s for s in decks.getSurfaces] gives you the list of instances of xc.QuadSurface objects in the set decks

Anallogously there exists methods getLines, getNodes, getElements, ...

Ana

[berndhahnebach]

got it. The only one left ATM for me is #33

[berndhahnebach]

is it possible to display the geometry group entries of workingModel without a fem mesh in a openGL window or to export them somehow tot dxf or whatever format?

[lcpt]

The geometry (points, lines surfaces...) is displayed by display_blocks.py...