tornado loadings

[rfdpe]

I need to know if the overpressure loading from a tornado varies with the tornado type. For instance, does a n F2 tornado have the same overpressure as a F3 toranado. What is this ovepressure loading. Where is a good source on designing a tornado resistant structure.

 

[JAE]

The "world" experts on tornados are at Texas Tech University.  We hired one of their professors some years ago to consult with us on designing a tornado resistant system for a backup recovery computer facility in San Antonio, TX.  They studied the lay of the land, amount of vegitation, types of projectiles that could be generated by a tornado in the area, etc. and then issued a report outlining their findings and recommendations.  What I remember them coming up with was a recommendation for wind speed and a minimum concrete thickness necessary for projectile resistance.