2.7.1 Drawing a section


The first thing to do is define the nodes. You can locate nodes graphically on the drawing window or enter the coordinates in the input fields. To add a node, click on \includegraphics[width=14pt]{./Images/newnode.png}.

If you are editing Example 10.5, try this. Click \includegraphics[width=14pt]{./Images/newnode.png}. A row for node 4 appears. Move the cursor to coordinates (10,10) on the grid. As you move the cursor over the grid, the coordinates are displayed on the table. Once you have it located, left click. That’s it! You have node 4.

Now click \includegraphics[width=14pt]{./Images/edit.png} for node 4. Move the cursor to position (20,20) and left click.

Now add a segment \includegraphics[width=14pt]{./Images/newsegment.png}. First select a laminate in the dropbox labeled Panel. Then, select the end nodes as follows: $n_ i$=3, $n_ f$=4. Click on the grid to finalize your selection. Voilà! You made a C section. When defining segments, pay attention to the direction of the segments, which are marked by arrows. The arrows indicate the direction of the shear flow. Everything is explained in Chapter Beams in the textbook.

You can move a node on the grid easily. Click on it once and the pointer changes to a hand. Now click on the place where you want the node to go and it’s done.

Each time you add a segment, the default is to assign it a Concentrated Stiffness (CS). If the segment you want to add is not a CS, you change that by selecting the laminate for the segment. Then, you select the end nodes in the drop boxes for segment $n_ i$ and $n_ f$. Now click anywhere on the grid to finalize you entry.

Finally, don’t forget to \includegraphics[width=14pt]{./Images/save.png}. If you don’t, your changes will not be saved.

Behold the power of CADEC! Each segment can be a different laminate. Each laminate can be a stack of several types of laminas (unidirectional, CSM, fabric-reinforced, even experimental!). And each lamina can be made of any fiber and matrix that you have in your database! Later update any property in the database and all the dependent objects are updated, automatically!

You will need Section Loads in order to analyze a Thin Walled Beam.

To do the analysis for a Section (which represents a Thin Walled Beam), go to Chapters/Beams.