##### Figure 1. The View commands

The View menu gives access to a number of tasks that display useful information about the cross-section under investigation. To access these commands, the following step must be completed first.

1. Load the problem you want to run and perform the finite element analysis.

Once this step is completed, you are ready to performs these ancillary tasks. Select the menu View, to reveal the commands shown in fig. 1. You can

1. Display the names of the topological entities of the section
2. Display the location of the origin of the coordinate system
3. Display the orientation of the principal axes of bending and the location of the centroid
4. Display the orientation of the principal axes of shearing and the location of the shear center
5. Display the orientation of the principal axes of inertia and the location of the center of mass

## Display the names of the topological entities (View→Names)

To mesh the cross-section, it is subdivided into simple topological entities that form triangles or quadrangles. Figure 2 shows the example of an elliptical section, which has been divided into five quadrangular faces, named Core, Quadrant1, Quadrant2, Quadrant3, and Quadrant4. Command View→Names toggles the display of the names of the topological entities. Figure 1 also displays the names of all the vertices of these faces. The vertices are highlighted by a black circle with their respective names. The names of the faces, edges and vertices of the model will be referred to in the output file. These topological entities are also used to describe the section; for instance see the description of the elliptical section.

## Display the location of the origin (View→Origin)

Figure 2 shows the origin of the coordinate system, denoted O, used to describe the cross-section. Command View→Origin toggles the display of the origin of the axis system, highlighted by a purple circle. The lines of action of the externally applied forces F1, F2, and F3 pass through point O.

## Display the principal axes of bending (View→P. Axes Bending)

The analysis of the sectional properties of the cross-section of beams leads to many important concepts. When the general problem decouples into the extension-bending and shear-torsion problems, the extension-bending problem involves two important quantities.

• The location of the centroid and
• The principal centroidal axes of bending.

Command View→P. Axes Bending toggles the display of the location of the centroid and of the orientation of the principal centroidal axes of bending. Figure 4 illustrates the effects of the command.

• It displays the location of the centroid, indicated by the symbol.
• Indicates the orientation of the principal centroidal axes of bending, b2c* and b3c*.
• Draws the bending stiffness ellipse [1].

## Display the principal axes of shearing (View→P. Axes Shearing)

The analysis of the sectional properties of the cross-section of beams leads to many important concepts. When the general problem decouples into the extension-bending and shear-torsion problems, the shear-torsion problem involves two important quantities.

• The location of the shear centre and
• The principal axes of shear at the shear center.

Command View→P. Axes Shearing toggles the display of the location of the shear centre and of the orientation of the principal axes of shear at the shear center. Figure 5 illustrates the effects of the command.

• It displays the location of the centroid, indicated by the symbol.
• Indicates the orientation of the principal axes of shear at the shear center, b2k* and b3k*.
• Draws the shearing stiffness ellipse [1].

## Display the principal axes of inertia (View→P. Axes Inertia)

The analysis of the sectional properties of the cross-section of beams leads to many important concepts. The analysis of the inertial characteristics of the section involves two important quantities.

• The location of the centre of mass and
• The principal axes of inertia at the centre of mass.

Command View→P. Axes Inertia toggles the display of the location of the centre of mass and of the orientation of the principal axes of inertia at the centre of mass. Figure 5 illustrates the effects of the command.

• It displays the location of the centre of mass, indicated by the symbol.
• Indicates the orientation of the principal axes of inertia at the centre of mass, b2m* and b3m*.
• Draws the moment of inertia ellipse [1].
##### Figure 5. Display the principal axes of inertia at the center of mass for the circular arc

[1] Bauchau, O.A. and Craig, J.I., Structural Analysis with Application to Aerospace Structures, Springer, Dordrecht, Heidelberg, London, New-York, 2009