When I calculate my modell i get the following error: instability of type 3 in RX direction
I have looked at the node but everything seems to be correct. I the releases box I have tried to tick off RX, but that did not help.
Solved! Go to Solution.
if the difference between these values is greater than 1e11 \ 1e12 program reports instability number 3.
It is related to big differences in stiffenes of elements for example very short elements exist in model = some inaccuracies.
You can check it this way: on dummy model select everything, make intersection, then open Bars table on View tab. Find shortests bars. Then locate nodes \ places on original model and correct location of nodes.
If it is not the case. Send me model. You already know how.
please find attached 2 files.
the first, AUVENT_V2, is calculated without sismic load and is free of instability.
the second, AUVENT_V2_SISMIQUE, contains sismic loads and shows instability.
Calculation report :
Elém. diagon. de la matrice de rigidité
Min/Max après décomposition: 4.067231e+002 2.066486e+015
Shortest calculaltion element : 0.16 m -> I think it's not too short
- How be sure than we can ignore this instability (after checking node displacements, shorts elements)?
- Is it possible to highlight calculation node?