Sounds Alas-scary …
Keep safe
Amities
Philippe
> Le 25 nov. 2019 à 09:36, Ken Norton <ken@xxxxxxxxxxx> a écrit :
>
> ...and the ground still shakes.
>
> We got a good 4.0 several days ago just to remind us that tectonic
> plates laugh at us and the earth can shake us off like a dog shakes
> off fleas.
>
> A year later and about 10% of the homes are still not inhabitable in
> Eagle River, (population 30,000), with some neighborhoods having over
> 30% of the homes red flagged and/or condemned. Several on our private
> street were red flagged. Every single one of our houses on our street
> shifted downhill 1-5 inches and all experienced various levels of
> structural damage--some quite extensive. $150,000-200,000 in damages
> is a pretty common amount. Ours has over $100,000 and counting and
> counting and counting... (fortunately, we rent!!!)
>
> Eagle River got hit the hardest as we're not only closest to the
> epicenter, but directly east of it and got the bulk of the energy
> release as it was highly directional. The business district was
> decimated, with numerous structures destroyed or damaged beyond
> repair. Things are slowly coming back to normal--kinda like during a
> recession when you have a number of stores closed. At one point or
> another, about half of the businesses have been closed for repairs or
> moved to other locations entirely. It was really misleading as
> structures had visible damage, but passed inspection, only to be
> condemned later once repairs were started and structural damage was
> found. (like steel beams broken, or voids under foundations).
>
> Due to the specifics of this earthquake, two or three story structures
> were affected the most. And Eagle River also experienced more damage
> because it is built on either glacier till or rock slides. Entire
> neighborhoods moved en-mass, including ours. Some houses were built on
> ground not properly prepared, and nearly all of those are bulldoze
> specials.
>
> The USGS has posted some interesting computer simulations on youtube
> of several high-rise buildings in Anchorage. The Atwood building is
> right downtown, while the Frontier and BP buildings are in midtown. (I
> currently work a couple blocks away from the Frontier building). You
> can see by these YouTubes just how fierce the east-west motion was and
> how the resonance really got some of these buildings doing some odd
> things. Gotta love steel.
>
> Atwood Building (November 30, 2018)
> https://youtu.be/9MlvLdnwLY4
>
> Frontier Building (November 30, 2018)
> https://youtu.be/BXhU5oeIgs0
>
> BP Building (November 30, 2018)
> https://youtu.be/NKOdkmrjYWA
>
> For comparison, here is the Atwood Building in the January 24, 2016
> earthquake that had a very different motion. The building did get
> signifiant changes to the shear wall structure which changed the way
> it moves as it was designed to twist in order to dampen movement.
> https://youtu.be/Nt0m5JWa62w
>
> AK Schnozz
> --
> _________________________________________________________________
> Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
> Archives: http://lists.thomasclausen.net/mailman/private/olympus/
> Themed Olympus Photo Exhibition: http://www.tope.nl/
>
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|