J
John Larkin
10:22:00 AM, just a few seconds ago.
John
John
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W
Winfield Hill
John Larkin wrote...
Near Hercules, CA - 10:21:34 PST - 3.4
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/ciim_display.html
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/40181915_ciim.pdf
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/ciim_download.html
Near Hercules, CA - 10:21:34 PST - 3.4
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/ciim_display.html
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/40181915_ciim.pdf
http://pasadena.wr.usgs.gov/shake/ca/STORE/X40181915/ciim_download.html
J
Joerg
Hello John,
Do you think everyone is ok? Didn't hear anything on local AM radio and
nothing on the SF Chronicle web site yet.
Regards, Joerg
Do you think everyone is ok? Didn't hear anything on local AM radio and
nothing on the SF Chronicle web site yet.
Regards, Joerg
J
John Larkin
It was only 3.4, just a gentle shake here. I doubt anything got broke.
But it reminds me that I just spent a few hundred K for seismic
upgrades on our new place, and it was probably a good idea.
John
J
Jim Thompson
Roll bars ?
...Jim Thompson
J
John Larkin
Roll bars ?
...Jim Thompson
Three *big* excavations in the dirt. Well, you jackhammer the floor
out first. Fill them with much concrete, rebar, and 14" I-beams
extending all the way to the roof; it's 3 stories. Rip off all the
flooring and the roof and replace with structural plywood. Now start
bolting and welding. Lots of inspectors get involved... concrete
sample crush tests, pull tests on epoxied bolts, rebar inspection,
plywood nail patterns, ultrasonics on all the welding.
This is pretty seriously downtown, and the entire front of the
building is a major Muni bus stop, which makes it all a lot more
interesting.
Wanna see pics?
John
J
Jim Thompson
Sure!
...Jim Thompson
J
Joerg
Hello John,
Oh man, I am more and more surprised you didn't relocate to some less
regulated place.
This all might make sense, some of it might not. When I see those
'earthquake measures' around here some of it is pathetic. Water heater
straps that get fastened with teeny bolts that any serious wrestler
could rip out of the stud in a second. A 5.0 could make the boiler do a
tango because they are always full of water. Well, at least it'll be
held by the gas pipe ...
Or the requirement to bolt to the foundation but anything on top is just
wood sticks and nails. Then they allow heavy tile roofs above which is
pretty much a guarantee that the house will pancake when the big one comes.
Regards, Joerg
Oh man, I am more and more surprised you didn't relocate to some less
regulated place.
This all might make sense, some of it might not. When I see those
'earthquake measures' around here some of it is pathetic. Water heater
straps that get fastened with teeny bolts that any serious wrestler
could rip out of the stud in a second. A 5.0 could make the boiler do a
tango because they are always full of water. Well, at least it'll be
held by the gas pipe ...
Or the requirement to bolt to the foundation but anything on top is just
wood sticks and nails. Then they allow heavy tile roofs above which is
pretty much a guarantee that the house will pancake when the big one comes.
Regards, Joerg
J
John Larkin
But we like it here. You'd think, from a pure economic view, we'd be
better off in Riverton, Wyoming or somewhere else where taxes are low
and real estate is free. But the really good people don't want to live
in Riverton, and people are our major asset.
Besides, owning a building five blocks from San Francisco City Hall
isn't a bad investment in itself. This town is still just thinking
about recovering from the dot-com bust, and commercial property is
still fairly cheap... per square foot, maybe 1/4 the price of
residential.
It's a seesaw: in 1998, anybody could find a job here but apartments
were simply unavailable, and commercial real estate was outrageous.
Now all those things are reversed.
Google Earth on 18 Otis, San Francisco. It used to be a fortune cookie
factory.
John
J
Joerg
Hello John,
But from "downtown" Riverton it's under 10 minutes to the airport. And a
keyboard is still considered the thang whar the keys to the John Deere
is kept. Nobody is going to complain when you crank the wood splitter
all day long or the dogs run loose.
Where we live it's two minutes to the airport. Not that there's a whole
lot of flight out of here but I can even jog to the FBO in under 10 minutes.
That sure sounds like a smart investment. Still I wouldn't want to live
in S.F. or any other big city for that matter. Been there, done that,
didn't like it. Life is too hectic there.
Regards, Joerg
But from "downtown" Riverton it's under 10 minutes to the airport. And a
keyboard is still considered the thang whar the keys to the John Deere
is kept. Nobody is going to complain when you crank the wood splitter
all day long or the dogs run loose.
Where we live it's two minutes to the airport. Not that there's a whole
lot of flight out of here but I can even jog to the FBO in under 10 minutes.
That sure sounds like a smart investment. Still I wouldn't want to live
in S.F. or any other big city for that matter. Been there, done that,
didn't like it. Life is too hectic there.
Regards, Joerg
Joerg said:
A few years ago the Scientific American had an interesting article on
Chinese temple construction - some of them have been standing for a
long time and have survived a lot of earthquakes.
It turns out that the standard heavy tile roof is always mounted on a
structure that allows the whole roof structure to jiggle from side to
side or back and forth during the earthquake - the roof itself stays in
one piece, and the supporting frames - wood sticks - distort without
breaking.
Maybe your regulations were originally writtne in Chinesse or Japanese.
John said:
Sounds like a very good investment. Pictures would be fascinating.
J
Joerg
Hello Bill,
I doubt it. What happens here is that many houses are originally built
with wood shake roofs. Then the insurance company says they won't renew
the contract unless the shake roof goes, too much fire danger. Some put
composition on it which, for you Europeans, would look like glorified
tar paper pieces with some finely crushed gravel sprinkled over it. That
doesn't look too upscale for many people so they opt for tile. An
engineer comes out, looks at whether or not the rafter construction can
hold that or not and then blesses the plan or not.
AFAICT the dynamic properties of a house are not looked at during that
assessment, just whether the trusses, rafters and load bearing walls are
strong enough to carry the tile. Now you have house that is top heavier
than it was before.
Regards, Joerg
I doubt it. What happens here is that many houses are originally built
with wood shake roofs. Then the insurance company says they won't renew
the contract unless the shake roof goes, too much fire danger. Some put
composition on it which, for you Europeans, would look like glorified
tar paper pieces with some finely crushed gravel sprinkled over it. That
doesn't look too upscale for many people so they opt for tile. An
engineer comes out, looks at whether or not the rafter construction can
hold that or not and then blesses the plan or not.
AFAICT the dynamic properties of a house are not looked at during that
assessment, just whether the trusses, rafters and load bearing walls are
strong enough to carry the tile. Now you have house that is top heavier
than it was before.
Regards, Joerg
J
John Larkin
Not to mention the cascade of tiles you'd prefer not to stand under.
In the '89 quake, the building next to ours was faced with brick, 7
stories high, and they all peeled off and fell on the sidewalk. It's a
busy street and it's a miracle nobody was walking there; one brick
would have killed you. I think 100% of the people who died in San
Francisco were in masonry buildings.
John
W
Winfield Hill
John Larkin wrote...
Yes please. Pretty please!
Yes please. Pretty please!
J
Joerg
Hello John,
That is indeed a miracle. Brick without reinforcement can be a problem.
But I believe the old saying that wood frame or other framed
construction is always better than brick and concrete is, to an extent,
a myth. We had an earthquake in Germany and our house didn't even
flinch. Despite a big heavy tile roof. Ok, I had to put a lot of stuff
in the attic back into the shelves, it was a mess and the hutch in the
living room suffered a big crack but nothing structural happened. One
reason may be that there is rebar in all poured concrete ceilings and in
the basement.
The frame construction of a nearby school gym didn't fare so well. IIRC
it had to be closed until further notice.
Regards, Joerg
That is indeed a miracle. Brick without reinforcement can be a problem.
But I believe the old saying that wood frame or other framed
construction is always better than brick and concrete is, to an extent,
a myth. We had an earthquake in Germany and our house didn't even
flinch. Despite a big heavy tile roof. Ok, I had to put a lot of stuff
in the attic back into the shelves, it was a mess and the hutch in the
living room suffered a big crack but nothing structural happened. One
reason may be that there is rebar in all poured concrete ceilings and in
the basement.
The frame construction of a nearby school gym didn't fare so well. IIRC
it had to be closed until further notice.
Regards, Joerg
Joerg said:
Me too, but made a cute closing line.
We had the equivalent of that in England - a house that started off
with a slate roof, replaced with ceramic tiles when the slates gave up
the ghost as they do after 60 to 80 year - the nail holes enlarge until
they are bigger than the nail heads.
The guy who surveyed the house did say that the roof beams were rathr
mean ... but they weren't sagging.
<snip>
K
Ken Taylor
No damage/people hurt I hope??John Larkin said:
Are the pic's available yet? We have to do seismic bracing over here in New
Zealand as it's a little shaky (more so further south; the capital has been
flattened in relatively recent history). Our bracing of racks and other
equipment at work is pretty solid stuff.
Cheers.
Ken
J
John Larkin
I posted a bunch to s.e.d. The building has poured concrete sides, and
the front/back are "soft", mostly doors and glass, so the hazard is
that it will parallelogram sideways, the sides will crumble and the
floors will break away, pancake, and squash everything inside. It's
1935-vintage concrete, not prestressed and not nearly as tough as
modern stuff. The plywood and steel and bolting are supposed to make
this less likely. All our parts racks and partitions and stuff will be
bolted to the walls, too.
Like our present place, it's mostly wood, RF-transparent, and in sight
of Sutro Tower, 25 megawatts of involuntary EMI testing.
The worst earthquake in modern US history was on the New Madrid fault,
1803 I think, near what is now Kansas City and Memphis; it sheared off
whole forests. Those cities take no earthquake precautions. Places
like New York and Boston get occasional severe quakes and would be
piles of rubble; fortunately the interval is 500 years or more.
John
J
Jim Thompson
On Sun, 18 Dec 2005 10:27:51 -0800, John Larkin
[snip]
They hope. Sounds like the same kind of disaster planning that took
down New Orleans.
...Jim Thompson
[snip]
They hope. Sounds like the same kind of disaster planning that took
down New Orleans.
...Jim Thompson
