This sounds like a professor at a university that won a contest with his students, it could well be employed in this manner, but it’s a far cry from being a standard material being used for bunker construction by a defense contractor.
BTW-Who does Iran use as a contractor for it’s bunkers or nuclear facilities? I’d bet it’s a Russian or German company.
Since Russia is building their reactor I would assume they are also pouring the concrete.
Or French....or Dutch.....or Belgian...or Italian....or Swedish....or Canadian....
Germans I believe. They seem to be the main bunker builders used by all ME regimes. As far as I know, construction grade concrete hasn't changed much, it's a matter of using good measurement of ingredients and exact amounts of water which determines the final strength of the concrete once it sets and cures. While it is possible to fine tune this in a lab making small amounts, thus resulting in higher strength concrete, this isn't as easy when pouring huge slabs and foundation walls in the field.