East Coast Earthquake 8-23-2011

Thu Aug 25 05:53:41 UTC 2011

On 8/24/2011 7:18 PM, Sean Donelan wrote:
> On Wed, 24 Aug 2011, Leigh Porter wrote:
>> Indeed, we are not going to be building earthquake proof buildings in 
>> London for example.
>
> Of course there is no such thing as earthquake proof.  The Earth is 
> still a single point of failure :-)
>
> Essential facilty design usally takes the "standard" design 
> probabilities for various hazards (heat, cold, wind, rain, earthquake, 
> etc) and multiplies it by a larger safety factor.  It doesn't mean 
> designing for
> the most extreme situation possible anywhere.  You've got to rely on the
> geologists and structual engineers to know their stuff.
>
> In any case, its still just a probability.  No matter how small the 
> probability, any facility can still have a failure.  Have a backup plan
> somewhere else with a different set of hazards.
>
>

Many years ago I was taught that "earthquake proof" means the building 
doesn't kill the occupants and not that the structure survives 
unscathed..    As examples, they used a hospital that was damaged in the 
magnitude 6.6 Sylmar quake of 1971  The building was basically destroyed 
but only four people were killed.