Years ago, in Southern California, I worked in the aerospace program. Our company used a great deal of cryogenic materials (mainly hydrogen, LOX and even played with FLOX) in addition to liquid hydrogen and petroleum compounds. Much of the structures were stainless and all our gratings and supports were stainless because they also supported the piping. I appreciate your situation.
All finished ground cover was concrete since asphalt was too good of a fuel. We were concerned about the concrete life since some splls occured around the tanks. There was no corporate or government money for a quick answer, so we conducted some non-scientific testing/observations - impact, chipping after repeated exposure. We did not have any numbers.
It appeared that higher strength air entrained concrete held up better, probably due to the entrained air voids, just as it does for freeze-thaw resistance.
Based on some other things I have seen in some Russian durability testing, I would suspect that lightweight concrete made with quality lightweight aggregate (not natural pumice, scoria, etc.) could offer some advantages because of the void structure. Manufactured rotary kiln expanded shale or clay (uncrushed in all sizes if possible) would be a good starting point. This also offers additional insulation compared to convential heavyweight concrete.
The lightweight aggregate producers may have some information on the subject. Google Gravelite, Arkalite and Livlite for possible information sources. The guru of the industry was a brilliant man, Thomas (Tom) Holm, who authored many very technical ASTM, ACI, etc. papers on the structural and other uses of lightweight aggregate. He has retired, but some of his information should be available.
I hope this helps you on your quest in this narrow application of concrete.
Dick
