RicodJour writes:

Hydraulic cement (and no, I don't like the name it is
marketed by any more than you do) expands slightly as it sets to offset
the natural shrinkage.

The proper term "hydraulic" has nothing to do with "expansive".

http://www.fhwa.dot.gov/infrastructu...rp/cement.html

"ASTM C 150 defines portland cement as "hydraulic cement (cement that not
only hardens by reacting with water but also forms a water-resistant
product) ...". That is, all portland cement is hydraulic.

By blending proportions of various aluminates, silicates, and sulfates in
portland cement, the shrinkage/expansion can be controlled. Shrinkage
typically has everything to do with inadequate hydration while curing and
not composition.