[CEUS-earthquake-hazards] FW: Report on estimating maximum magnitude in the Central and Eastern US.

[Wang, Zhenming]

Time is a fundamental element that must be considered in any activity.


-----Original Message-----
From: Krinitzsky, Ellis L ERDC-GSL-MS Emeritus [mailto:Ellis.L.Krinitzsky at usace.army.mil] 
Sent: Thursday, May 07, 2009 10:01 AM
To: Central and Eastern U.S. Earthquake Hazards Listserve
Cc: Wang, Zhenming
Subject: RE: [CEUS-earthquake-hazards] Report on estimating maximum magnitude in the Central and Eastern US.

Everything depends on the criticality of the structure. If the structure is
critical (the consequences of failure are intolerable) then one must design
for the maximum earthquake regardless of temporality. Otherwise, it is proper
to design on a cost-risk basis.

Nobody can say that a 1,000-year earthquake or a 10,000-year, both based on
150-year record, will not happen tomorrow. The 10,000-year earthquake,
assuming the time estimate has any meaning, could just as well be more likely
to happen.

Ellis Krinitzsky
Corps of Engineers, ERDC, Vicksburg