
1) Concrete
Found on
https://www.crosswordclues.com/clue/mass-concrete

Mass concrete – is defined by American Concrete Institute Committee 207 as `any volume of concrete with dimensions large enough to require that measures be taken to cope with the generation of heat from hydration of cement and attendant volume change to minimize cracking.” As interior temperature of mass concrete rises due to the process of .....
Found on
http://en.wikipedia.org/wiki/Mass_concrete

Any large volume of concrete cast in place intended to resist applied loads by virtue of mass. Generally a monolithic structure incorporating a low cement factor with a high proportion of large coarse aggregate.
Found on
https://www.encyclo.co.uk/local/21066
No exact match found.