The maximum ground motion was 0.8 g, and 40 cm/s. Nearly all of the seismic energy of the quake was directed down, so this a very low ground motion for an M7. As an example, look at the Kobe, Japan earthquake M7, where all the energy was directed up.
So, Anchorage dodged a bullet. I just picked up this last ground motion, and I'll go into a long explanation for Penny.
The main damage from an earthquake is from shaking. There can also be ground slips, and landslides. Your frame house is quite secure up to 50 cm/s, but you'll lost your knick-knacks. Use tacky mounting stuff to secure your valuables. Those in Anchorage might think about using latches on the cupboards. You can also strap down the hot water heater.
Once you get above 50 cm/s, the foundation cracks, and you get serious structural damage. Still, the house shouldn't kill you until 100 cm/s. Even then, it will be the chimney. :)
I always use peak ground velocity (PGV) as an indicator of damage. I've done the literature, and numerical analysis, and it perfectly scales with damage. The more standard peak ground acceleration (PGA) is useless on soft ground and should be scrapped. This is the Grand Stupidity in earthquake engineering. It results in a lot of tilted buildings.
We haven't learned anything from this earthquake. However, in couple of months (give or take decades) the big M8 should rip through the whole rift. Then we'll learn something.
ps. Anchorage should upgrade enough to shrug off 40 cm/s, and go on with normal business. They seem to have achieved this (I would styrofoam the road ramps). The next step is to not have anybody killed up to 100 cm/s. That may need work.
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