The June edition of Grassroots Motorsports has an article " Concrete Conundrum " , page 111. Must be too early for the article to be referenced on line, search did not return any results.
GM lists theses alternatives with comments:
Paint
Epoxy floor covering
Stained or dyed concrete
Plastic mats
Plastic tiles
Polished concrete
Recapped is the application of UCoat on their, GM , 50 year old concrete. Also mentioned Ucoat used in Jay Leno's shop
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