yorik wrote: ↑Thu Oct 04, 2018 2:50 pm

I don't know staad pro

I would try to tell about StaadPro.

A beam or column in StaadPro (or for that matter any other Structural Analysis software (Finite Element or Stiffness method based )), is represented by its end points (called nodes, which are 3D points), like wise slab can be represented by 4 nodes or 3 nodes, and brick can be represented by 8 nodes.

After telling element's (Beam/Column) position in space using 2 points, we need to tell cross-section's geometric properties, which can be Area, Moment of Inertia and more like that (for prismatic members, though it can also handle non-prismatic (tapered) members):

AX = Cross sectional area

IX = Torsional constant

IY = Moment of inertia (MoI) about y-axis.

IZ = Moment of inertia about z-axis.

In addition, the user may choose to specify the following properties:

AY = Effective shear area for shear force parallel to local y-axis.

AZ = Effective shear area for shear force parallel to local z-axis.

YD = Depth of section parallel to local y-axis.

ZD = Depth of section parallel to local z-axis.

One way is give such values directly, and 2nd way is telling the type of section i.e. circular (Give dia), rectangular (give size Depth x Width) or Trapezoidal, T and I section, then programme will calculate Area, MoI and do needful.

Line:

1 PRIS YD 500 ZD 300

which is line no. 134 of

https://bitbucket.org/hsrai/staad-pro/s ... ew-default
tells that section 1 is prismatic, with width 300 and depth 500.

yorik wrote: ↑Thu Oct 04, 2018 2:50 pm

three structural elements (one beam and 2 columns, and each of them is made of a 2D polyline that gets extruded to form a volume

It will be nice, if IFC from FreeeCAD can identify such common cases like rectangular (IfcRectangleProfileDef)/ circular / T sections, and for other irregular X-section, IfcArbitraryClosedProfileDef should be OK, but in staad-pro it must translate to AX, IY etc.

yorik wrote: ↑Thu Oct 04, 2018 2:50 pm

each of them has the "Concrete" material associated.

In StaadPro, material is defined as:

DEFINE MATERIAL START

ISOTROPIC M25CONC

E 22000

POISSON 0.15

END DEFINE MATERIAL

Lines 116 - 125 of

https://bitbucket.org/hsrai/staad-pro/s ... ew-default