Posted by: ccckkkk
Wind load parameters - 09/08/18 11:59 PM
Hi ,
When we select ASCE as the specified wind code and taken into CII calculation , how do we consider the parameter for structure damping coeff. ? CII marked the typical value could be 0.03 ; however, it can't be found that the specified valuces defined in ASCE code , is any reasonable reason to use 0.03 as default value ?
Thanks
Posted by: Dave Diehl
Re: Wind load parameters - 09/10/18 10:02 AM
Older documents (USNRC and ASME III) listed piping system damping values of 1% to 3% for seismic use. These sources now show 5% critical damping. In my opinion this change was implemented to better-match actual system performance regarding seismic events.
Usually lower damping will simply increase the applied model load so lower damping may be considered more conservative.
Posted by: ccckkkk
Re: Wind load parameters - 09/12/18 04:08 AM
Hi Dave ,
Thanks for your reply and I will think it in deep.
Regards,