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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

More Tsunami Basics

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Phases of a Tsunami Event:

•Generation

•Propagation

•Shoaling

•Inundation

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Shoaling

Wave steepens and breaks because of decreasing depth:

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Forces on a structure:

Hydrostatic (pressure) forceBuoyant ForceHydrodynamic Force

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Forces on a structure:

Hydrostatic (pressure) forceBuoyant ForceHydrodynamic ForceSurge ForceImpact ForceBreaking Wave Force

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Here is an example of a broken wave (or bore) hitting a square column in a laboratory:

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Hydrodynamic forces on a structure on a structure:Here is what the lateral force looks like on the square column during impact

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

For the modelers in the audience, here is the same thing on a computer:

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

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Catherine Petroff, University of Washington - July 22, 2007UW Educational Outreach – Tsunami Science & Preparedness Program (Su 07)

Let’s do a brief exercise:

Light wood construction

2x4 studs, light plaster both sides 19psf

Floor wood 4 psf

Roof wood 3 psf

5 meters square

1 psf = 48 Newtons/m2

Velocity?Asafa Powell 100

meters in 9.77s, 2006 Zurich

http://nctr.pmel.noaa.gov/education/science/docs/floatorfall.xls