Edit/Review Beam Sections

Edit and review any type of beam section.

  1. From the Beam Section Browser, right-click on any beam section and select Edit.
    The Section Manager opens.
  2. From the Section Manager, select sections from the browser list to navigate between the sections.
    Note: The name of the opened section is displayed in the top-left corner of the Section Manager.

    The Section Manager invokes the Sketch ribbon. For sections from the database, the Sketch tools are grayed out, since their shape cannot be edited; otherwise, the tools are available for normal use.

Section Parts Tab

The Part tab contains information about sketch line grouping and the attributes used to compute section properties.

There are two types of parts:
Shell Parts
A ShellPart is defined by one or more continuous curves. Not all ShellParts are necessarily connected.
The characteristic size of a ShellPart is its Thickness, which can be updated from the corresponding table column.
If the beam section is configured as Elastic, the ShellPart may or may not have a Material assigned. If it has a valid material, the ID corresponds to the one in the Materials list. If no material is assigned, it is considered Geometric.
For a Shell beam section, the SectionPart cannot be assigned a material.
Solid Parts
A SolidPart is defined by a group of one or more curves forming a closed loop.
A SolidPart may optionally contain one or more SolidParts as inner parts. In this case, the inner part can be a hole or an inclusion (with a different material).
The characteristic size of a SolidPart is its MeshSize, which defines the average element size used when meshing the section. The default MeshSize is 0.0, in which case it is automatically computed using a global area-based metric.
If the beam section is configured as Elastic, the SolidPart may or may not have a Material assigned. If no material is assigned, it can be Geometric or a Hole.
For a Solid beam section, the SectionPart cannot be assigned a material and can only be Geometric or a Hole.

Properties Tab

Whenever engines compute the section properties of the current section, they are displayed in the Properties tab.

Figure 1. Section Manager Properties tab


Cross Sectional Properties

The beam cross section is always defined in a y,z plane.

The x-axis is defined along the beam axis. The coordinate system you define is called the local coordinate system; the system parallel to the local coordinate system with the origin in the centroid is called the centroidal coordinate system; the system referring to the principal bending axes is called the principal coordinate system.

For shell sections, only the theory of thin-walled bars is used. This means that for the calculation of the moments and product of inertia, terms of higher order of the shell thickness t are neglected. Thickness warping is also neglected.
Area
Figure 2.
Area Moments of Inertia
Figure 3.
Area Products of Inertia
Figure 4.
Radius of Gyration
Figure 5.
Elastic Section Modulus
Figure 6.
Max Coordinate Extension
Figure 7.
Plastic Section Modulus
Figure 8.
Torsional Constant
Solid
Figure 9.
ω - Warping function
(see below for warping function)
Shell Open
Figure 10.
t - Shell thickness
Shell Closed
Figure 11.
Ami - Area enclosed by cell i
Fsi - Shear flow in cell i
Elastic Torsion Modulus
Solid
Figure 12.
Shell Open
Figure 13.
Shell Closed
Figure 14.
Shear Center
Figure 15.
Warping Constant (normalized to the shear center)
Figure 16.
Shear Deformation Coefficients
Figure 17.
Shear Stiffness Factors
Figure 18.
Shear Stiffness
Figure 19.
Warping Function
Figure 20.
For solid sections, the warping function is computed using a finite element formulation. This may lead to un-physically high stresses in geometric singularities (sharp corners) that get worse with mesh refinement. This may cause problems computing the elastic torsion modulus.

Nastran-type Notation

Figure 21.
Figure 22.
Figure 23.
Figure 24.
Figure 25.

Section Manager Toolbar

Access additional tools from the Section Manager toolbar.

The toolbar, located at the top of the window, contains the following tools:
Tool Function Behavior
Split Parts Splits one or more ShellParts defined by two or more curves. Enabled only if applicable ShellParts are selected.
Merge Parts Merges two or more ShellParts is they form a continuous path. Enabled only if ShellParts are selected. Limitations on t juntions.
Convert Casts SolidParts to ShellParts (or vice versa). This command is available only for Elastic section types, since only the FEM engine can handle both shell and solid parts.

Shell parts need to form a closed loop to be converted into a Solid part.
Delete Deletes selected Parts.
Centroid On-off state to draw centroid in sketch.
Shear Center On-off state to draw shear center in sketch.
Plastic Center On-off state to draw plastic center in sketch.

Graphics Window

Access additional features from the graphics window.

In addition to standard Sketch graphics, all sections display the following items:
Item Description
Section Centroid
Shear Center
Element Axis
There is a two-way selection mode in the Section Manager:
  1. From the Sketch graphical window, select a line(s) to highlight the corresponding part(s).
    Figure 26. Lines graphical selection behavior


  2. From the Part table, select a Part(s) to highlight all corresponding sketch lines in the graphical area.
    Figure 27. Part selection from table behavior