Writing code for P-M Interaction Diagram Question

[mfstructural]

I am currently trying to write VBA code to go through a SAP 2000 output text file and check combined axial load and out of plane flexure for each shell element in the text file. There are about 4000 elements and 216 load cases being considered. That's the reason for a VBA code as opposed to something more simple. I'm having trouble understanding how to check the allowable P and M against a given P and M. I know that for a given P and M, I know the eccentricity. The equation to compute the allowable axial load and allowable bending moment is based on knowing the distance to the neutral axis from compression face, c. However, how do I know what "c" is for a given P and M from SAP? I'm am a structural engineer but it has been a while since I looked at this. I guess I'm asking for advice on how to program this in general.
Thanks

 

[brengine]

Excel can easily handle 4000 rows of data, and it'd (probably) be easier than resorting to VBA.

 

[mfstructural]

There are 4000 elements with 4 nodes per element with 216 load cases for each element. This is over 3 million lines of data. I understand what EXCEL can do but understand this is the way the client would like it done.