THE PROGRESSIVE COLLAPSE CHALLENGE
Your structure can be made out of anything: straws, toothpicks, cards, dominoes, mud, vegetables, pancakes, etc.
The designers of the Twin Towers were able to meet all 5 challenges using steel and concrete.
CHALLENGE #1:
Build a structure with a vertical aspect ratio of at least 2 (twice as tall as it is wide) and induce it to undergo top-down total progressive collapse.
CHALLENGE #2:
Build a structure with a square footprint and a vertical aspect ratio of at least 6.5 (6.5 times as high as it is wide), and induce it to undergo top-down total progressive collapse.
CHALLENGE #3:
Build a structure as required by CHALLENGE #2 which, in the process of collapsing, will throw pieces outward in all directions such that at least 80% of the mass of the materials ends up lying outside of the footprint, but their center of mass lies inside the footprint.
CHALLENGE #4:
Build a structure as required by CHALLENGE #2 which is capable of remaining intact in 100 MPH cross wind.
CHALLENGE #5:
Build a structure that meets the requirements of both CHALLENGES #3 and #4.
Thanks to Mr. Hoffman for this challenge.