Down stand grillage BEF model

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Permalink Reply by peter fotiadis on December 3, 2015 at 4:23am

Like this?

Notify if you need some more fun stuff (see the grid option) like orienting HEB/HEA/I/C profiles and creating the load bearing assembly (+ the V "columns") as "solids".

Attachments:

• beam_grids_V1.gh, 15 KB

Permalink Reply by Kenyon Graham on December 3, 2015 at 7:57pm

Peter,

Many thanks for taking the time over my definition issues. my printer got frazzled in a power surge due to lightning. Apologies for not providing you with a sketch.

After taking some time to go and sulk in the corner, my C# is non existent, although i am making progress on python unfortunately slower than my grasshopper.

Attached is a typical relatively simple planar grillage model for a bridge form that is common in Australia/NZ/Asia. The analysis package has a good graphical interface, however i am looking at replicating the process ideally with GH. I am getting there.

There are a few constraints in the use of a super T, the precast mould is governed by two critical dimensions:

1. from the beams soffit to the underside of the precast flange, normally Depth -75 or 100mm. Depths that are common are 1200/1500/1800.

2.The real sweet spot dimension is the 1027mm dimension to the outside of the webs, this is a constraint

The actual shapes of the prestressed beams are governened by AS5100:5 Appendix H (from memory)

In my definition I included the super T cross section which is parametric.

The other definition is where I have got to with the grillage.

I am a little one dimensional: point-line-surface-volume. I think I am getting to grips with manageing data i lists.

My ulimate aim is to:

• generate basic geometry in gh, the type of analysis will be a space frame or FE, these analysis types require different geometries imported to a structural analysis package
• ideally utilise IFC, for materials, 2D, 3D drawings and project documentation

At the moment I am looking to generate all of my gemetry in GH, that seems to generate a lot of doubled up geometry. Deconstruct Brep may become my favourite.

A little excesive is the inclined members spilt into the same no. of points at the grillage length.

again thanks for you time, oh! took a a few minutes to work out how to plug your def's in.

kenyon

Attachments:

• Lusas grill Rev A.gh, 43 KB
• Box Beam and Slab Analysis - Super T Sections.pdf, 1.1 MB

Permalink Reply by peter fotiadis on December 4, 2015 at 12:11am

Hmm ... this is rather easy:

1. First see some primitive IPE/C "maker" geared to the grid option (obviously it doesn't do the things that you want since this simple test is made PRIOR your PDF):

2. With regard your specific case: (a) Create the suitable "grid" (the C# grid requires a few lines more to do what you want) (b) Create suitable parametric profiles (at WorldXY) and define "on-the-fly" an instance definition (nested or "flat") containing the extruded "solids" (c) place the instances using classic plane to plane transformation (kinda like the Orient component). Steps b,c require code ... but is 10000 times faster VS orienting a "seed" solid (or more) in N planes - meaning actually "copy,transform and paste" (and that's especially true when the "solids" are complex). 

I could rather easily provide a demo on all these ... but using solely code and that MAY not be an ideal solution for you.