unable to achieve the eigenvalue problem- result is the imaginary or null

[erdemck]

Dear all,

I have issue that couldnt manage on the bridge which has the 3 bays, as you see from subject explanation, i couldnt get the accurate vibrated modes.
Bridge has the piles, standart abutment and piers, plus it has the spring with nonlinear for the shear keys and elastomer designing. The big prestressed superstructure is defined by the user defined mode.
If any author requested i can attached the file.
But where is the problem all nodes are setted as for the right DOF or restrained .
Looking forward to hearing from you??

[z.gronti]

Dear erdemck,

You should check for the correct modelling and if you have connected all the members properly in your model.

[erdemck]

Dear z.gronti,

I have checked and you are correct that some link connection behav is not similar with the sap designing.
So i tied node by node carefully and then it was solved.
Thanks for your answer.

[erdemck]

I need to clarify one more thing that about bearing hardening ratio parameters.
Default config is assigned by 0,2, however i couldnt decided for my bridge, my elastomer bearing dimensions 250mmx400mmx52mm,
It has 5 plates and plates thickness is 2mm.
Can you suggest any source or research about that matter?