Even better, no TV
That roof held, but I could tell it was heavily overloaded. I had mocked it up to try to understand how they work. There is one in speedfunk's post above. I then calculated the breaking load on the model roof system and realized it was mighty close. I stood on it and had my wife start handing me books. Low tech but this is what it looks like after failure, a bending and then horizontal shear failure. I did several more and had all bending failures.
I gotta admit, in the wintertime, kindling is coming in and it just doesn't seem right not to play with it one last time
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This is another "hand in hand" frame. The floor system in Independence Hall is based on this beam arrangement.
The concept behind these is neat, they are self supporting. A reciprocal frame is a "closed circuit which is self supporting". In old floor designs it was a 2 dimensional structure often called "grillage". In more recent designs roofs are being framed in 3 dimensions.
At our snow load I figured up a small carport type structure out of logs on the DaVinci model. At ~24' wide x 16' deep it would take 3 bents using 6" minimum dia logs 10' long. 21 of those, 12 long purlin logs and rafter logs. Not a large pile, and of forest thinnings diameter.
