The hydraulic composition having resistance to carbonation IMPROVED

The present invention relates to the use of at least one cross-linked polyacrylamide in the form of particulate powder having a mean size of 300 .mu.m to 2000 .mu.m, said crosslinked polyacrylamide having a higher nitrogen content than or equal to 4% by weight based on the weight of said polyacrylamide in combination with at least one hydraulic binder in a hydraulic composition, for reducing and / or preventing carbonation within said hydraulic composition, said one or polyacrylamide (s) crosslinked (s ) is present (s) in said hydraulic composition in a weight ratio polyacrylamide (s) polymer (s) / binder including from 0.01% to 5.0%.