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Designing Module to go in 70% of the World

Designing Module to go in 70% of the World

Designing Module to go in 70% of the World

If you were told to design a process module than could be plunked down pretty much any place in 70% of the livable land mass of the world, what seismic criteria would you use? I'm in the U.S. so I picked some S1 and Ss values along with risk category III and site class E that would allow it to go in probably around 90% of the U.S. Do you think this would fit the criteria?

I realize there are different codes all over the world and this is not a simple problem. Just trying to get a feel for it. Thanks.

RE: Designing Module to go in 70% of the World

Will they be permanent emplacements, or picked up and moved from time to time?

Best bet would be to ask more questions and figure out which 70% they want to get to and look for the worst case. Link.

RE: Designing Module to go in 70% of the World

These would be permanent. This is a request from sales so they have no idea what 70%. About the best they can do is narrow it down to several continents.
Looking for the worst case is the crux of my question. With all the codes worldwide and lack of data that I can found outside the U.S., it's tough. I use the ASCE 7 Hazard tool for determining seismic conditions of sites in the US but I haven't found anything like that for the world. Even if I did I would then have to magically become an expert on the countries building code that has high seismic activity.

RE: Designing Module to go in 70% of the World

I've posted this link before, but this has a good global research map of PGA around the world if you want to locate where your worst case spots might be. I've done some conversion from Chinese Building Code to ASCE 7 but I won't be much help outside of that.


RE: Designing Module to go in 70% of the World

Thanks Luceid. That's definitely a step in the right direction.

RE: Designing Module to go in 70% of the World

IDK how you can possibly rely on something like global PGA maps. Site specific soil conditions can have a large impact on seismic. I would think you want to design for 100%. Or for seismic look into performance based design and over capacity.

RE: Designing Module to go in 70% of the World

If the module is covered the regulations of the country it is installed in then that sets the seismic design levels. Which may them depend of the risk level and design life of the equipment.

We work in high seismic risk country, we could draw a line round the PGA contours (and soil types) with 70% of the country below that contour and design for that, but there would a number of cities where the equipment could not be installed.

RE: Designing Module to go in 70% of the World

Check the DOD's Unified Facilities Criteria, specifically the structural engineering section. There are a lot of overseas military installations, so they include several OCONUS locations with data tailored to US design methods.

RE: Designing Module to go in 70% of the World

Drift, you are absolutely right. My intention when using that map is never to get any design value, but it helps for a gut check level comparison between two locations (especially in a country somewhere else around the world that I know nothing about the seismicity of). I use it as a big picture: oh okay cool: type of “research.”

RE: Designing Module to go in 70% of the World

Are you also designing for the worst case snow load and worst case wind load in 70% of the livable world?

Depending on what 70% we're talking about, snow could control (anywhere from Canada on north) or wind could control (possibly anywhere with an ocean coastline).

Oh, the load combinations.......

Not to mention license reciprocity in 70% of 180 countries (assuming those countries even have license regulations)

Gotta love sales folks.

RE: Designing Module to go in 70% of the World

I think this is pretty much pie in the sky, but I had to give them something. The various levels will have grating so we're not too worried about snow. I gave them a very high number for wind. I did tell them extreme northern latitudes (I guess southern for that matter) have their own issues like possibly needing low temperature steel and it just wasn't worth trying to design something that could go in these type of areas.

Yes, licensing and local codes could be a nightmare. Maybe it's just my negative outlook but it seems to me that for the piping if it meets ASME B31.3 and for vessels if it meets ASME BPVC Section VIII then everyone is as happy as a pig in slop. But when it comes to civil/structural everybody has their own code which makes it extremely hard (impossible?) to design a one size fits all.

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