• TechNotes
• Core-Only Display of Composite Structures

When sending data to structural engineers, it is frequently a requirement to show only the Structural Core of Composite Structures.

Currently this is not possible in ArchiCAD at the switch of a button, but there are several possibilities to achieve the desired result.

Modeling the Core separately

One way is to model structural elements on separate layers. In case of Walls, two possibilities may be considered. The first one is to create a Composite with 2D representation for the Core, and also create the Core only on a separate Layer (a Layer containing structural elements).

A different approach: the Composite Structure uses a 2D Representation that does not show the Core. In this case, you will have the Layers of both elements shown to see a correct architectural representation (Here you need to make sure the Structural elements are in front of nonstructural elements in Display Order). When you need the structural representation, you only need the structural Layer shown.

The advantage of these first two methods is that the structure will be correctly represented in both 2D and 3D (3D Window/Sections/Elevation etc.).

Their disadvantage is twofold: a) more modeling is required and b) if there is any change in the location of these elements or the skins of any of the Composite Structures, again you need to make sure elements on the Structural Layers are also changed accordingly.

Changing 2D Representation only

If you need to provide only Floor Plan data to the Structural Engineer, without any 3D model data, there are two other possibilities. Both involve modifying attributes of these composites so they look exactly as required. This is done by not showing those skins/skin separation lines/end lines that are not necessary for a Structural View.

The first method involves the definition of a new Pen Set. In the Composite Structures Dialog Box (Options > Element Attributes > Composites), select the Composite Structure you want to work with.

Next, change the the Pens used for its Core fill /outline so that they are not used in any other skin fills/outlines (Here, we changed Core Pens from 27, 107 and 127 to 21, 101 and 121, respectively).

Now go to the Pens and Colors Dialog Box (Options > Element Attributes > Pens and Colors).

Here, change all pens used in the fills/outlines of non-core skins to a White color. When done, save the new Pen Set under a new name (Here, we changed Pens 1, 47, 67 and 107).

Then, when a Structural View is needed, just apply this new Pen Set.

Note: Make sure that the line and pen settings in the Structure and Cut Surfaces part of the element's Settings are set to "Apply Structure's Settings."

The advantage of this method is that you can use it simply by changing the Pen Set. In ArchiCAD 11 and later, this means that switching to the desired saved View also applies the Pen Set (since in these versions, Pen Set settings are saved with Views).

The disadvantage is that a) the 3D model does not change accordingly and b) those fills/contours are still there - they are just colored White - so you must make sure they do not overlap something accidentally.

The other 2D method involves duplicating the Composite Structure you wish to work with and redefining the Composite Structure. In this redefined Composite Structure, the Core remains as it is. All other contours and skin end lines are set to Hide. All other fills are set to Empty Fill and all other Fill backgrounds are set to the value of -1 (Window background).

Now, every time you have to send data to the Structural Engineer, you can either select and change the desired Composites to this modified Composite, or you can duplicate those Composites on another Layer and change the element on that Layer, so it can be shown and exported when needed.

The advantage of this is that it looks perfect in 2D since skin fills/contours are really hidden and not just White as in the previous method. Its disadvantages are a) the 3D model does not change accordingly and b) you need to either change the Composites each time before sending data, then change them back afterwards (or save before changing, change data, then revert back to the saved version), or you have to make sure the duplicate structural Layer data stays in coordination with the architectural layers’ data whenever there is a change.

Category3dModeling