Maximum Mapped Response Acceleration Ss problem

[magner]

Hi,

I am building a (static seismic) piping model in a seismic area class 2A (Libya).

Looking at the input box. located in model tab at the top of page> Seismic wizard.

I am having trouble locating an explanation of where max. response acceleration (ss) figure comes from.

Following the help recommendation to chapter 22 of ANSI 7, I find maps for the united states. reading the explanation box on p344:

"The number on the fault is the deterministic median spectral response acceleration times 1.5"

Not to sure if this relates to the 1.5 figure which is automatically inputted into the ss input box when you first open seismic wizard.

Any help would be appreciated.

 

[DDiehl]

There's a nice application from USGS to provide Ss for all US locations. Take a look at

http://earthquake.usgs.gov/hazards/designmaps/

click on that Java Ground Motion Parameter Calculator.
Great info & background but that won't give Lybia data.
You might also look at

http://www.hnd.usace.army.mil/techinfo/ti/809-04/ti80904.htm

Chapter 3 has lots of good background and has estimates for Ss around the world using UBC as the basis.
I will not say the data is current and is does not address fault proximity.