Need a book? Engineering books recommendations...
Re: Need feedback from those using strict interpretation for Woodstructures[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: seaint(--nospam--at)seaint.org
- Subject: Re: Need feedback from those using strict interpretation for Woodstructures
- From: FEMCCLURE(--nospam--at)aol.com
- Date: Sat, 31 Jul 1999 21:59:24 EDT
- Cc: FEMCCLURE(--nospam--at)aol.com
Lynn Howard, In the subject email message, "Need feedback from those using strict interpretations for Woodstructures, you stated: "We are supposed to be designing for the earthquake that has a 10% chance of reoccurring every 50 years." According to the 1997 UBC, Division IV-Earthquake Design, the correct definition of the "Design Basis Ground Motion is that ground motion that has a 10% chance of being exceeded in 50 years as determined by a site-specific hazard analysis or may be determined from a hazard map." This Design Basis Ground Motion has a MEAN RETURN PERIOD of 475 year with a mean annual probability of exceedance of .002 or .2%. There is nothing in this definition that addresses the question of the recurrence time for the design basis ground motion. Earthquakes are defined by their probability of being exceeded in a certain number of years or their MEAN RETURN PERIOD, not their chance of recurrence in so many years or their recurrence period like the time for the return of Haley's comet. Frank E. McClure FEMCCLURE(--nospam--at)aol.com July 31, 1999.
- Prev by Subject: Re: Need feedback from those using strict interpretation forWoodstructures
- Next by Subject: Re: Need feedback from those using strict interpretation for Woodstructures
- Previous by thread: Re: Seismology Committee Meeting August 13 to review Wood Draft of Blue Book
- Next by thread: Re: Need feedback from those using strict interpretation forWoodstructures