Ha, this gets a full post, but it really is an addendum. The other 'Easter Egg' they gave us in the famous California report, is the holy treatment of peak acceleration. This came from early film strong motion recorders that only put out acceleration as a body force, like gravity. In other words, a pendulum.
This religious assumption probably cost the 30,000 lives in the Ven earthquake, and many thousands before that. It is that you can determine structural loads by treating the earthquake ground motions as a body force, like tilting the building. This is so wrong, I just grind my teeth. But, as an engineer once said to me "How else can we operate?"
By using the Scientific Method with Physics! Anyway, this system downplayed soft basins by a factor of 10 or more. Oh, you are on a nice soft cushion that reduces the pga. No need to design anything.
And a million people die (maybe too much?). What kills the building, my friend, is base shear. This is directly correlated to peak ground velocity, or pgv. No other indicator need apply. We have a standard factor of 10 amplification of pgv on soft basins.
I want world standards of 20 cm/s for 'riding it out untouched' and cracking at 40 cm/s and sides fall off at 80 cm/s. Even 100 cm/s should leave most of the slabs supported. All this is easy with steel and real concrete. Guatemala does this, and it should be easy in the US drug supplier countries.
This also goes against the Shake Table Industry, as evil as anything trumpy ever did. Just add to the death count.
ps oh, and shout-out to growing out own Coca leaves in Canada. The US drug demand has rendered all these countries non-operational. We want a slice of that action!
ps this wonderful 'buildings are a pendulum' has given us soft-story condos all over the place. Also, they will not find any example 'complex vibration modes' in the observations.
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