Retrieving the Properties of a Beam Section

This task shows you how to compute beam properties from ply sections defined on your models, to analyze the structure using finite elements.

In a beam model, the finite element analysis requires information about the structural behavior of the beam, namely how it responds to loads. These properties of the beam depend on the shape and size of the beam and the material properties. In the case of a Composites structure, this can be a very complex problem, as the cross-section may contain many plies, using different materials which have non-isotropic properties.

Ply Section Beam Properties proposes an easy way to compute these properties. From the intersection of a plane with a cross-section you have defined, Ply Section Beam Properties computes the outline of the cross-section. The section is displayed in the graphic area while the Composites layup is retrieved to compute the necessary properties. You can then export the properties to a spreadsheet.

Available in Composites Engineering Design (CPE).

Open the BeamSections1.CATPart document.
Sections must already exist.

Click Ply Section Beam Properties in the Analysis toolbar.
The Section Properties dialog box is displayed:

It is populated with the sections found in the model.
Select the sections to process in the list.
Only planar sections can be processed.

Select a coordinates system to define a frame of reference:

Its X-axis and Y-Axis are projected on the section plane.
All sections need to be parallel to that XY plane.
The intersection of its Z-axis with the section plane defines the origin used to compute the properties.

If you do not select a coordinates system, Section Properties uses the origin and the axes of the section plane instead. In that case, it is your responsibility to define a consistent plane.

Click ... to enter the path and the name of the spreadsheet to create.

Click OK to validate.

The following beam properties are exported to the spreadsheet.

Parameter Name
in the Spreadsheet Description Support in
Analytical Solution

Section Name Name of the cross section (string) -

E Average Youngs modulus Yes

AREA Cross-sectional area Yes

EA Product of E and AREA Yes

El11 Bending stiffness for axis 1 Yes

El12 Cross bending stiffness Yes

El22 Bending stiffness for axis 2 Yes

GJ Torsional stiffness No

MASS Mass per unit length Yes

I11 Moment of inertia for axis 1 Yes

I12 Moment of product of inertia Yes

I22 Moment of inertia for axis 2 Yes

XY1m Beam center of mass, x Yes

XY2m Beam center of mass, y Yes

GA11 Transverse shear stiffness, axis 1 No

GA22 Transverse shear stiffness, axis 2 No

GA12 Transverse shear stiffness, cross product No

XY1c Beam centroid location, x Yes

XY2c Beam centroid location, y Yes

XY1s Shear center location, x No

XY2s Shear center location, y No

AI11 Area moment of inertia about 1-axis Yes

AI22 Area moment of inertia about 2-axis Yes

AI12 Area moment of inertia for cross-bending Yes

Ox Global x position of section origin Yes

Oy Global y position of section origin Yes

Oz Global z position of section origin Yes

AX1x First component of section x-axis Yes

AX1y Second component of section x-axis Yes

AX1z Third component of section x-axis Yes

AX2x First component of section y-axis Yes

AX2y Second component of section y-axis Yes

AX2z Third component of section y-axis Yes