Article in S.F. Chronicle regarding the raising of a 500,000 lb dome from the old Emporium so a new building could be built underneath it (maybe someone can tell me exactly how the jacks work that they used…):
http://sfgate.com/cgi-bin/article.cgi?file=/c/a/2004/05/19/MNG066O85V1.DTL
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Based on the graphic it looks more like they're hoisting it than jacking it. The 30-foot lifts appear to be the height that the interior of the dome can accommodate in terms of a structure built within to do the lifting. Lift, support, reset hoists, lift, support, reset hoists, etc. House movers use unitary hydraulic jacks that go between 1 and 2 feet per shot, and then are reset on another 2 or 3 courses of cribbing.
I'm not sure I can imagine working under that dome to build the new building. I'd pucker up every time the wind blew.