Attendees of the Bridges 2009
Math & Art conference are in the process of building the largest Zometool
sculpture ever. It will be ~12 feet high and wide if completed, and consume 24000 parts IIRC. There isn't a master digital model yet, but the portion of the model that I do have was run through a simple structural analysis program of mine and shows significant tensional stresses at the narrow junctions.
Red is for segments in tension, blue is for compression. Since the magnitudes of the peak tension and compression forces are roughly equivalent, I have to conclude that if the structure does break, it will be a tensional pull-out failure, and will occur on the undersides of the narrow junction regions.
(cross-posted to my own journal, apologies to those who have to see it twice)