An example of Response spectrum analysis?

[rikhan]

Hi there,
Does anyone has a simple example for response spectrum analysis in ANSYS with excitations in more than one directions?
I have an idea that it will involve few load case commands but I need a reference to validate my macro.

Thanks in advance

 

[Drej]

Assume you've checked the help file and found the sample response spectrum analysis in there (Structural Guide> Chapter 6. Spectrum Analysis> 6.5 Sample)? I know this is only unidirectional response, but this falls into your "simple" request. The only difference with more than one direction is that you need to deal with cross (SRSS etc.) combinations of results not just modal (unidirectional) combinations (CQC, SRSS, GROUP, DSUM). You don't need an example for that, you need to read some literature on dynamics of structures and the response spectrum method (clough & penzien is a good choice

http://www.amazon.co.uk/exec/obidos...627/sr=1-1/ref=sr_1_8_1/026-5696886-3087627);

ANSYS deals with cross combination of modes using the jobname.mcom file (read in using the /input command in a post session). This is a big area of work to be involved in, and unfortunately the complexities don't allow a simple answer.

Cheers,

-- drej --