I Need a Concrete Cross Section Analysis Tool that May Not Exist 2

[KootK]

I would like a tool that would allow me to determine the moment of inertia of the cracked, transformed section of the shear wall group below for a given location and angle of the neutral axis. I know, it's asking a lot. Anybody know of such a thing? Our own member Denial has something close for arbitrary solid sections but I don't believe that would handle the voids.

 

[Celt83]

Ah think I am on the same page, thanks for including those notes very much appreciated!.

I've been heavily researching the parabolic stress blocks as well as biaxial ULS analysis and found two great references in ACI journals recently by Desayi and another by Collins. I am still in the very early stages of trying to approach biaxial ULS or even SLS analysis of regular/irregular concrete cross sections. I've been looking into green's theorem a bit since I think it would/could be applied so you could do the line integrals across the polygon edges knowing the stress/strain values and get the total compressive force on the area but I'm a bit out of my depth on this currently.

From my research and being honest how I understand it/explain it to myself the I,cracked-PNA I am calculating would be a lower bound elastic cracked moment of inertia since at Mp an assumption is uniform stress across the transformed area. So I say that, but I have also found that this is not entirely accurate with the respect to the real conditions because if the look at the actual moment-curvature diagram the I,cracked-PNA determined in this way would be a bit above and too the left of the actual Mp location.



Open Source Structural Applications:

https://github.com/buddyd16/Structural-Engineering

 

[Celt83]

Re-read your original post KootK and just re-uploaded my script now you can specify an axis angle and depth and get the elastic transformed Icracked about that axis rotation and depth. Optionally you can set the NA depth to 0 and it will find the PNA at the defined angle.


Open Source Structural Applications:

https://github.com/buddyd16/Structural-Engineering