workshop domes - handy little tensegrity domes & shells (2006-10)

this geodesic framework is hemispherical, 16 feet in diameter, 8 feet high at the center, made of 1/2-inch conduit pipe.  it will be covered with a solid thin shell made of chicken wire screen covered with a few layers of fabric scraps (old t-shirts, bedsheets, etc) which have been soaked in a thin solution of homemade hypo-allergenic vegetable glue and thrown onto the wire screen to dry.  after the shell is complete, the relatively expensive conduit frame can be removed and used as the form for another shell...

[dome09cv.jpg 44k photo]

again, the geometry is based on a one-frequency dodecahedral tensegrity.  this frame is made of 1/2-inch EMT conduit pipe, 35 main struts 5 feet long, 30 stellation struts of 4.4 feet, and 10 ground-anchor struts (about 1.6 feet), all connected with 26 bolts (5/16-inch coarse thread).  total cost of materials for the frame is about $150 from any retail hardware store, and about 3 person-days of labor with a saber saw, hammer & anvil, grinder, and drill press to prepare the strut ends.

once the struts have been fabricated, the frame is easily & quickly assembled / disassembled by 1 or 2 people, and this "dome kit" is relatively small & easy to store and transport.  this size and layout is much easier to assemble than greenhouse dome 98 (which had 10-foot main struts).  also, orientation with a 10-sided base gives a peaked pentagonal roof for better drainage, and it's easier to secure a 25 by 25 foot sheet of greenhouse plastic or canvas all around the edges of the base.

[dome09dsdk.jpg 36k photo]
stress testing by diarmuid & david  (vansprouts photos)
( more photos in progress... )
also see - rebar dome design - victoria's rebar dome - greenhouse dome 98 - webliography - dome cat