I am wondering if anyone can provide some advice on the best way to create an interaction diagram for axial and bending.

For example, a reinforced concrete column.

The basic process to form an interaction diagram is to assume the location of the neutral axis then to perform a bunch of smaller calculations/checks and finally end up with the column axial and bending strength.

If I want to plot these results do I need to set up the calculation so that all these small steps are part of the same 'for loop'?

Or if I want to calculate the moment and axial strength at certain points then plot the result of these points; I suppose I could just repeat (copy/paste) the calculation for each point and record the Moment and Axial capacity then plot these values.

Any thoughts on this?

I can attached a spreadsheet or calc of what I'm trying to accomplish if that would help.

You can compute the moment/axial force pairs individually, append them to a 2 column matrix and plot that matrix. Best results are obtained with the X-Y-Plot plugin by Viacheslav N. Mezentsev (uni).

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First, thank you.

Second, quick question, in the 'for' statement shown above (for i from 1 to n+1) how do you get the two periods (the "to" part of it)? What keys are pressed?

a..b is the operator form of the function range(a,b).

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Martin,

I'm taking a look at this again...
I seem to be having an issue getting this to plot.

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Interaction - Graph.sm (7 KiB) downloaded 95 time(s).

Hello,

What exactly is your issue? As I could see, you just did not change the scale for X-Y plot and therefore did not see your data plotted.

Regards,
Radovan