AFAIK this design has been invented back in 1935 by Albert Caquot and first put in application in the so-called "Forme Caquot", later "Forme Jean-Bart" in Saint Nazaire, France, where battleship Jean Bart has been assembled in 1936-1940.
This design allowed multiple builds and repairs in a single dock.
This dock has been dismanteled for years in favour of dry areas with huge cranes and is now the place where giant passenger ships are being prefabricated and assembled.
Not to be confounded with the "Forme Normandie" which is a very large conventional dock farther down the Loire river.