Seismosoft | Earthquake Engineering Solutions

I have a problem with defining dashpot element at the base of my system. I also use a linear link element at the base and running dynamic time history analysis.

1) When I complete the analysis, total base shear of system is a very huge number like 2500-3000 kN, although total base shear seems to be 180-190kN when I remove the dashpot and link element.

2) And displacements are the same in both cases (considering and not considering dashpot) and I am not sure whether the damper is working or not.

Is there a way to be sure that the modelling is true or can you have a look at my system?

Best Regards.

The results seem to be consistent with your model, considering that dashpots are fixed to the ground, as explained in the Help System.
The question is, are you sure a dashpot is what you need? What are you trying to model, some sort of damping device? If so, then using a link with an adequate nonlinear response curve, or a link with a linear response curve plus 'element damping' might be a better option.

Seismosoft Support

I had already fixed the dashpots and links to the ground as it is written in Help System.The very huge base shear I mentioned was found with this model.
I am trying to do "soil structure interaction analysis" and I want to model soil with horizantal and rocking springs and dampers as it was done in literature previously, that's why I am using link elments and dashpot elements for my system. (The values are
Kx=F1=1940877 kN/m, Kyy=M2=37861651 kNm/rad, Cx=8742 tonne/sec and Cyy=92866 tonne*m^2/sec. These values are obtained based on a study of Wolf et al.)
So what can be the problem or is there a way to overcome?
Best regards.

We are not specialists in SSI. However, as we mentioned before, we tend to believe that a linear spring with associated element damping is the most adequate modelling approach.

Seismosoft Support