Geometric Nonlinearity

[ammar]

Hi All,

Glad to see that this forum is finally been resurrected, good work.

I am trying to perform second-order inelastic dynamic analysis. I can see that nonlinearBeamColumn can do material nonlineairity, but does it do geometric nonlinearity as well?

I read a comment on top of the source file indicating that P-Delta effect included, but not sure if it is meant from a stability stand point or a full second-order analysis (updating geometry and tangent stiffness in each step and performing element state determination according to the new geometry?).

Thanks.


-ammar

[Boris Jeremic]

Hello Ammar,

You can also try to use the Total Lagrangian brick elements
we put in there and test the outcome. Might be an overkill for a beam analysis but perhaps good for testing...

Boris

[fmk]

you can use the corotational transformation with the force (nonlinearBeamColumn) and displlacement beam column elements.

[ninoit]

I'm very involved in geometrically non linear analysis in this period. I tried some simple example with Opensees ElasticBeam and CorotCrdTransf. The examples worked fine so i got a look to the source code but i didn't find the source code of CorotCrdTransf classes (only the .h and the corotational.lib files are available). Can anyone help me? Thank you!

[fmk]

send email to Prof. Filippou (fillippou@ce.berkeley.edu) if you want to look at the source code .. the theory is in Crissfields book.