Lagos, Nigeria and adjacent regions design parameters

[e104909]

Hi,

Our office has a prospect project in Lagos Nigeria. I'm looking at the normal parameters used in designing structures and foundations in this region to somehow give a brief intro to our proposed team and start creating our design criteria. I'm used to structures designed in the United States where you can get initial parameters online through some legitimate websites. Can you recommend any good websites for seismic and wind information? does wind normally govern in this country?

Do they typically use Euro codes or still BS codes?

For foundation design, can you share your experiences if typically you have done mostly piles in this area? Though Geo report is a must, Can you share your experiences in the past?


Thanks for your inputs. Any bits of advice or recommendations will be appreciated.

Regards,
E104909
Civ-Str P.E.

 

[MrHershey]

I usually throw out the US military code (UFC 3-301-01), it's often helpful in getting you in the ballpark for environmental load parameters (wind, seismic, snow) in areas outside the US.

This looks to be an exception though.

Looks like they don't have much wind data for Africa, none anywhere near Nigeria. Obviously no snow data. Seismic values they list for Lagos are so small that I'd worry they're incorrect. UFC lists Ss = 0.3% g (so 0.003g) and S1 = 0.1% g (so 0.001g). I know Nigeria isn't often mentioned as a seismically active area, but those numbers are less than the lowest numbers I've seen anywhere in the US by a factor of at least 10. So probably merits double- or triple-checking with other sources.

Outside of the UFC I've also had luck finding data from local universities and academic publications in the region. Have heard others throw out organizations like Engineers Without Borders as potential resources, but haven't gone that route myself. Organizations like EWB probably won't know the answer themselves but may be able to hook you up with either a local engineer or a remote engineer familiar with working in the region.

 

[Lomarandil]

Another good source for seismic info is the Global Seismic Hazard Assessment Program.

They list a 10% in 50 year PGA for Lagos of 0.0-0.2m/s^2 -- so 0.02g at maximum. An approximate conversion to Ss would be 0.1g, S1 = 0.04g.

In short -- you're not going to be controlled by seismic.

----
The name is a long story -- just call me Lo.