SUBS #9:
The Theory of Voids

What's wrong with this story?

A man with a vacant lot put up some 12'x12' SUBS units for swap meeters to rent.  As his business grew, he gradually covered his lot until all the separate swap meet units bolted up together into one great big building, twelve units by twelve units.  Over the years, he added a second and a third story.

When his daughter wanted to be a ballerina he built her a clear span ice skating rink by removing the four unit by four unit section in the middle of the first floor [about 50'x50'].   Of course, when the center walls of the building were removed, the floors above fell down and killed them both.

(end of story)

? What's wrong with the story ?

The idiot built her a skating rink to be a ballerina?
No, that's perfectly logical.

What's wrong with the story is that, in actual fact,
NOTHING FELL DOWN!

Well . . . why DIDN'T the ceiling of the ice rink [the floor of the second story] come crashing down and kill them?

Because the second and third floors are a gigantic box beam internally criss-crossed with 29 [count'em!] rigidly interlocked shear planes and the 50'x50' "unsupported" second floor is part of the bottom surface of that beam, hung with hundreds of bolts from the very same connectors it always was . . . but those connectors are now HUNG from the walls they formerly SUPPORTED.  [Turnabout, fair play, and all that.]  The weight formerly supported by the now missing walls is transferred to the four unit wide first floor outside ring of the building, which supports the twelve unit by twelve unit two story thick box beam of the upper floors.

The girl became a world famous ice ballerina.

Bill Dur <billdur@net-prophet.net>

modular.systems * Simple Universal Building System * "Superior By Design"