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Does anyone have a good reference on how to choose the best option for system, numberer and algorithm commands? My model includes soil, structure and soil spring elements and I have been doing that mostly by try and error so far, but I was wondering if someone has done this in a more systematic way ...

1. Being able to assign different convergence criteria to different regions (i.e. soil and structure). 2. It would also be nice to record the residuals (in "test" command) in different elements to get a sense of which part of the model is problematic. This is helpful when the model consist...

Hey Frank, Could you please explain more on what you mean by current/last/committed stiffnesses (or any reference)? I'm using San Diego's model (i.e. highly nonlinear). Within one time step, the solver iterates to find the yield surface, so there is an initial stiffness and a current stiffness withi...

I suggest using the following syntax instead of the one online: element nonlinearBeamColumn $eleTag $nodeI $nodeJ $transfTag $intRule $SecTag $numIntPnt And $intRule could be "Legendre", "Lobatto", etc. In this case you know exactly where the intgr points are located. Then use re...

Hi,

Is there any way to save the unbalance force of each analysis in a file, rather than just showing it on the screen?

Thanks

I used -xml. It showes eta being 0 and L but when I divide the recorded moment by the applied force (to back-calculate the location of the ip) it is +/- 0.3333 (in range of [-1 +1]). It might be an integration error though, i.e. 2 integration pnts might not be accurate enough to integrate the polyno...

Thank you Frank,

I double checked 2 point and got +/-0.3333 instead. Even when I use UseDefined it still gives +/-0.3333.
Also I think UserDefined gets pt locations between 0 and 1.

Thank you,
Arash

I'm not sure if my post delivered correctly, so I'm posting it again, sorry for duplicate. Hi, I have a problem finding the locations of ip's in dispBeamColumn element. In the manual the integration rule is mentioned to be "Gauss-Legendre quadrature", whereas when I back-calculate the loca...

Hi Silvia, Can I modify the nodal constraints during an analysis, say between two load patterns? I tried it and didn't work, so my question, in another word, is that how can I erase the previously defined "fix" command and assign new constraints with a new "fix" command. Thank yo...