Foundation to Roof Columns with different size shapes at specific floor heights

[Anonymous]

I have tried to make a Member Style that has a square column section of 450x450mm from 0 to 8000 in height. From 8000-12000 I would like the column shape be 400x400mm.

I have tried using nodes to make this work but I can never get the column to display properly.

These are the settings I think should work: (the shape is basically a 1 unit square)

                                    Start Shape                                 |              End Shape

Component   Name   Relative to  Node  Scale  XOffset   |      Name   Relative to  Node  Scale  XOffset

1F-2F              SQ          Start            0      450      0                 SQ       Start           1     450      8000

3F                   SQ          Start            1      400     8000            SQ       Start           2     400     12000

Does the X Offset always refer to the Member's start point or the the previous node point?

I saw in the instructions about a process to draw a multi-segment polyline, make a rigid frame tool and applying that but it seemed like something useful for a roof beam and not a column. Ideally I would like to have a multi-segmented column where I could snap to a node and stretch it to a floor level to change the location of the shift from one column size to another.

Tips greatly appreciated!

[David_W_Koch · Accepted solution]

The offsets are relative to the Start or End of the referenced node.  If you want a column that is always 8000 long for the first size and 4000 long for the second, you can make a single node structural member with two components that have the appropriate offsets at start and end.  If you want a multi-segment structural member where you can adjust the point at which the shapes change, then something similar to the image below should work for you.  Just such a member is defined in the attached file, and two 12000-long instances placed.  One has the specified 8000/4000 split in sizes; the other started as a copy of that, in which the intermediate node was stretched down 10000.

To add an instance of that style, I drew a polyline with two co-linear segments, the first 8000 long and the second 4000 long, by setting the Front UCS active temporarily.  After drawing the polyline, I switched back to the World UCS.  A copy of that polyline can be found in the attached file, with one end at 0,0,0.  I tried drawing an instance of the column using the multi-node style and the COLUMNADD command, to get that style set as the default style.  Then I made use of the Column tool on the out-of-the-box Design tool palette (in the Design tool palette group).  I right clicked on the tool and chose Apply Tool Properties To > Linework, as shown in the image below.

I selected the polyline, and then cleared both checkmarks in the Convert to Column dialog.  If you want to get rid of the polyline, you can leave the Erase Layout Geometry toggle checked, but do not check the One Member Per Polyline Segment toggle, as you want the nodes of the polyline to be the nodes in your style.

Once it is created, you get a grip at the intermediate node that can be used to set where the change in size occurs.

[Anonymous]

Thanks David-

You always make it look so easy.

[Anonymous]

Follow Up Post

I did not get the same results as you, but it seems to be a drawing setting related issue.

I modified my Structural Member Size as you suggested and I didn't quite get the same results. When I used COLUMNADD to set the current style then placed a column the resulting column had an alert symbol on it. Ignoring that I used the Apply Tool Properties to Linework option but the resulting column was Standard style. Not to be deterred I selected the column and changed the style in the PROPERTIES palette to C3 (My column definition). The column disappeared or rather it was an invisible column. I could see the node points but as soon as it was unselected I could not see anything

I then imported the style you created and tried using that but got the same results.

Then I tried the opposite way and imported my style into your drawing and it worked as you suggested. There appears to be an issue with the drawing file that I cannot determine. My only guess is that I used a template file created in AutoCAD so that I could get my layer settings. I have created additional drawings from scratch, using Architecture and AutoCAD templates and they both seem to work fine.

At this point I will start over with a new drawing. I have attached my problematic one in case your curious as to what may be causing this not to work.

Thanks again!

Tom

[David_W_Koch]

The alert symbol in the columns in your attached file was there because my style was expecting to have two segments, but the column to which it was assigned only had one.  I was able to use one of your two-segment polylines, convert it to a column and then change the style to my style and it worked.

You may also have run into display issues, since the file was started with an AutoCAD template (or came from a file with an AutoCAD template).  It is easier to move layers between files than it is to copy display settings; I would recommend starting with an ACA template file and moving the layers.