The 10/50 Seismic Acceleration
The 10/50 Seismic Acceleration
(OP)
I'm working on a project in California in a high-seismic region. The geotechnical engineer recommended use of Ss and S1 based on a 10% chance of exceedance in a 50-year period, instead of the normal standard of 2% for seismic and wind. The 10/50 seismic accelerations are about half of the 2/50.
When is it acceptable to use a 10% exceedance probability? This is an Occupancy Category II, two-story building.
When is it acceptable to use a 10% exceedance probability? This is an Occupancy Category II, two-story building.






RE: The 10/50 Seismic Acceleration
RE: The 10/50 Seismic Acceleration
So, why would the Geotech suggest doing that? I wonder if the Geotech would be willing to stamp the structural calcs.
MJ
RE: The 10/50 Seismic Acceleration
10/50 is the data which was originally published by the USGS in 1991. It is used by various federal agencies for design, although not necessarily for buildings. See the link.
http://pubs.usgs.gov/of/1995/596/appxC.html
the USGS hazards map site also lists 10/50, 5/50 and 2/50 maps all updated in 2008.
http://geohazards.usgs.gov/hazards/apps/cmaps/
RE: The 10/50 Seismic Acceleration
RE: The 10/50 Seismic Acceleration
RE: The 10/50 Seismic Acceleration