Forum for OpenSees users to post questions, comments, etc. on the use of the OpenSees interpreter, OpenSees.exe
Moderators: silvia , selimgunay , Moderators
from tongji
Posts: 94 Joined: Fri May 11, 2007 9:53 pm
Location: tongji university
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by from tongji » Wed Nov 14, 2007 6:49 pm
silvia, I found that if there are some additional nodes,Opensees can't converge.
silvia
Posts: 3909 Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
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by silvia » Wed Nov 14, 2007 7:51 pm
yeah,
i think all nodes need to to be connected, i believe.
at least the eigensolver doesn't like it....
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104
fmk
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by fmk » Wed Nov 14, 2007 10:06 pm
no hanging nodes are allowed .. OpenSees will typically fail to converge with an error from the solver if there are any rigid body modes in the moel.
from tongji
Posts: 94 Joined: Fri May 11, 2007 9:53 pm
Location: tongji university
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by from tongji » Wed Nov 14, 2007 10:13 pm
This should be revised. additional node shouldn't influence the result. in other software,such as ANSYS, sap2000, this doesn't occur.
Gang Wang
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Location: HKUST
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by Gang Wang » Mon Nov 19, 2007 10:23 am
I am curious about your remark. But, on what occasion do you really need hanging nodes? Impact analysis?
fmk
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by fmk » Mon Nov 19, 2007 3:30 pm
there are no need for hanging nodes and we do not plan on allowing them .. by flagging it as an error we are more likely to be catching modelling errors, e.g. someone messing up with their element connectivity, which on large models can be impossible to spot in a gui.