Shaking could be worst than we thought.
The University of Washington and the United States Geological Survey have been working on what they call the M9 Project.
Their work has looked at coastal tsunamis on the Washington and Oregon coasts and of particular interest to us here in Washington state, and how the Seattle Basin will impact shaking by an earthquake.
One of the significant findings is that buildings over 10 stories tall will experience shaking that is much greater than what the building codes envisioned when they were constructed. This impacts many fairly modern buildings in the downtown core.
They don't say it this way in the briefing I just reviewed, but my interpretation is that building codes are meant to prevent the pancaking of buildings, which allows occupants to safely evacuate the building after an earthquake. This new research indicates that for those taller buildings, there could be some significant damages to the structures, pancaking or even toppling over?
This is the type of information that businesses that operate from these buildings, the city building department and building code reviewers and emergency managers will find unsettling — indeed!