Shake tables, earthquake simulators and pull tests can replicate forces similar to those that occur in earthquakes, but the earthquakes themselves provide even more valuable on what we do right, and unfortunately what we do wrong when preparing for the next time the ground starts moving under our feet.

The information gathered from the actual quakes over the last year or so will take a long time to decipher, as rescue turns to rebuilding, and countries are left with the dire consequences of perhaps a false sense of preparedness pre-earthquake.

So what are some of the things we have learned?

Haiti Earthquake - Building Codes matter, and we can build buildings that do not fall down in earthquakes.  Also, the P Wave - or Primary Wave; that initial jolt, can bring down buildings and destroy environments within the first 10 seconds.  People don't always have the time to consider whether or not the shaking is bad enough to drop, cover and hold on.

Chile Earthquake - Building Codes matter, and we can construct buildings that won't fall down even in enormous shaking.  Building codes do not have a continuity to building occupancy post disaster.  just because a building does not fall down does not mean it is functioning after the quake.  Suspended ceilings and fire sprinkler failure, and furniture being tossed about can knock a business off line for months.  Many will never recover.  Also, Subduction zone quakes can cause damage from hundreds of miles.  Vancouver BC to Eureka CA is a distance of hundreds of miles.  Everything in between is next to a subduction zone.

Christ Church Earthquake - The ground can move with more in a 6.3 earthquake than with an 8.8 earthquake.  Thrust faults breaking near the surface can create a huge amount of damage.  There are a lot of thrust faults around Los Angeles. 

Japan Earthquake - When we prepare for events that are statistically, in our estimation, 1 in 500 year events, such as the japan tsunami, we will be caught off guard when the actual quake is far worse.  The Sylmar and Northridge earthquakes were both 1 in 10000 year event, according to our best guesses.  Perhaps we don't have enough history of statistical data to accurately predict earthquake frequency, or perhaps all the rules regarding earthquakes are changing all around us.