Friction stiffness factor

Dear All,

In one of the projects, for achieving frequency in modal run, we use friction stiffness factor as 1000.

Client asking for guideline/basis for using 1000 as a factor.

How to determine this friction stiffness value, whether I have to use 100, 200, 300 etc.,

Please let me know any idea of this topic

Thanks,

ANY HELP

Please see http://www.coade.com/uploads/caesar%20ii/webinars/may-2011-webinar.pdf
under title "Stiffness Factor for Friction".

I think there the key sentence is "Use it as a tuning parameter in forensic engineering.".

Vs this sentence, your wording "for achieving frequency in modal run" is unclear. You tried to achieve compliance with an observed frequency or you tried to achieve a target frequency considering nonlinear effect of friction? For the last one I think the following post gives a fair answer
http://forums.coade.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=47517

My opinion is that a large range of values will have very minor effect in most modal analyses.

The only time it could have a major effect is if CAESAR treats the support as sliding when it potentially isn't.

If this is the case, then selecting specific values of friction stiffness is about as scientific as specifying friction values in static analysis.

Thank all for sharing your ideas