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peymannp wrote:
> Hello everyone
> I have a question which is related to this error.
> Is it possible that after some step(after earthquake subjection) the system
> looses its constraint?
>
>
> bests

I'm also interested in this question.

Basa wrote: > Nikos, when you used elastic beam column elements (except from the natural period) > did you have any convergence regarding the reaction forces of beams and columns > between SAP2000 and OpenSees? And if not, did you have convergence when you used > non linear elements with elastic sec...

Thank you for your advice. It is clear that if the analysis fails and it does not achieve the desired displacement, an error is returned and a "FAILURE" message is printed. But, couldn't this message also suggest a numerical convergence failure (meaning that the whole response until collap...

fmk wrote: > that message is coming from the analyze command .. so the analysis at the current > step has failed .. if 1 step fails, you can of course do other things to move the > analysis forward .. i suggest you look at the following basic pushover example: > > http://opensees.berkeley.edu/wiki/i...

Dear All, Say that I'm performing a displacement-controlled Pushover analysis of an RC structure. I need to clarify the meaning of the "analyse failed, returned : -3 error flag" message, which occurs sometimes after several steps and stops the recording of the control node displacements. D...

fmk wrote: > did you try with elastic materials before the nonlinear ones .. if same > problem, use elastic elements to see if you got your section definitions > correct. if different prolem, see what happens without the aggregator. Dear fmk, thank you for your reply. I checked the fiber section def...

Anyone..?

Deal All, I have modeled a simple 3D 1-floor, 4-columns RC building with fiber sections and nonlinear beamcolumn elements, incorporating elastic torsional stiffness in each fiber command like this ##section Fiber $secTag <-GJ $GJ> {...## and using a section aggregator for every fiber section in orde...

UPDATE --- At last , I managed to solve the problem and I feel I should share it with anyone who may be interested. It seems that elastic BeamColumn element does not account for shear stiffness of members. I concluded this after a series of tests with stiffness properties modifiers on SAP2000 ( I se...

soko wrote: > Hello! > I am trying to perform a 3D Gravity Analysis of an 8-storey buidling model. This > particular building consists mostly of bare frames and has 5 small walls surrounding > the elevetor and the stairwell. I have allready modeled this building using both > SAP2000 and Opensees wit...

Basa wrote: > Nikos CV did u solve your problem? Thank you for your concern! No, unfortunately not yet. Strangely enough, the input I insert to both programms is exactly the same, but results differ (~10% divergence for the first natural period of vibration). It is significant for me to achieve a go...

sb1966 wrote: > Hi, > The following post may be of use. http://opensees.berkeley.edu/community/viewtopic.php?f=2&t=29144 > Thanks. Thanks a lot for your answer! Sadly, I haven't managed to find the root of the problem, so I am in a dead end. The strange thing is that, when I run an eigen analysi...

If anyone has a clue, I would really appreciate it.
This is about my post-graduate thesis, which includes concrete shear walls modelling with linear beam elements among others, and is crucial for me.

Thank you.

Hello! I am trying to simulate a simple 1-storey elasticBeamColumn 3D building with OpenSees and I would be grateful for your help. A 3D picture of the building is given on this link http://i1311.photobucket.com/albums/s663/stereotype232323/sapwallmodel_zpsbcd0b9e6.jpg A modal analysis of this on SA...

Thank you Tas!

That's very disappointing...