Most of the damaged buildings are on mud and were hit with 40 cm/s. This is exactly the same as Christchurch. Their difficult choice is to certify the remaining buildings for occupation. The problem is that there is no sign of damage, so this whole thing about 'inspection' is a farce.
In Christchurch, NZ, a building had no observable damage, it was occupied, and then was hit by the exact same ground motion. It collapsed and killed many people.
Japan is a walled garden for earthquakes, just like California. I like Taiwan, but they make their buildings out of tin cans. A ground motion of 40 cm/s on mud leaves a lot of 'dead man walking' buildings. They are dead, but don't know it. I fully expect the bravado that they know what they are doing, and blah, blah.
First, they don't need to inspect buildings on the firm ground at 10 cm/s. They are fine. If they had read my stuff, they would have run tests on all the buildings before the earthquake, and determined the stiffness. Then they could run the tests again, and see if the building softened. For example a building resonating at 8 Hz, should be 8 Hz after the earthquake. If it is 4 Hz, demolish it.
However, we all know what will happen. They will approve the buildings and the next earthquake down the fault road will happen. Lots of people killed.
All the replacement buildings there should be on deep piles.
ps. and I love the fact that meteorologists are in charge of earthquakes.
pps. these pictures are typical of 40 cm/s on mud
As usual, more info is gained by looking at the houses around it.
more: wow, Japan is having a rash of stupidity.
lots: from the Chile earthquake -- nobody learns anything.
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