how to include damping in a shock study

[cobra46]

Hi All,

I need to perform a shock study that included damping. From all my research, a Response Spectrum Analysis is the study used for shock. I don't see where damping can be included in this study.

Is there another study I can use for shock that would include damping. My customer has given me a Shock Response Spectra (Freq versus peak acceleration) and a damping value.

Thanks for your input.

 

[FEA way]

Response spectrum analysis will be the right choice in this case. Damping can be specified in material properties.

 

[cobra46]

Duh - I now recall seeing this option if I use CQC.

I think I forgot about this because not all my materials have a damping factor specified in the material properties and wanted to globally set it like I did in my random study. It won't be too hard to go in and artificially set them all to 5% which the customer wants.

Thanks for the quick response. My Monday will be much smoother now.

 

[statist1]

Hi. Response spectrum is conservative analysis, which calculate quickly. You use damping for get the level of load. It's analysis not simple how look.
You need to read this article of mr. Irvine:

https://www.vibrationdata.com/tutorials2/srs_intr.pdf

You also can use transient analysis for shock.

 

[FEA way]

When it comes to literature, I'd also recommend "Response Spectrum Method in Seismic Analysis and Design of Structures" by A.K. Gupta.

 

[statist1]

I recommend too Christian Lalanne(auth.) - Mechanical Shock_ Mechanical Vibration and Shock Analysis, Volume 2, Second Edition (2009, Wiley-ISTE)
In this book also explayning responce spectrum analysis for shock. The problem is precisely in getting the load. To do this, you need to use another application.