Mitigating Autogeneous Shrinkage by Internal Curing.
Mitigating Autogeneous Shrinkage by Internal Curing.
(144 K)
Geiker, M. R.; Bentz, D. P.; Jensen, O. M.
Special Publication 218;
High-Performance Structural Lightweight Concrete.
American Concrete Institute Special Publication 218.
Proceedings. 2004, Ries, J. P.; Holm, T. A.,
Editor(s)(s), 143-148 pp, 2004.
Keywords:
curing agents; shrinkage; deformation; cracking
(fracturing); aggregates; mortar; water supply; sand;
autogenous deformation; cement hydration; lightweight
aggregates; superabsorbent polymers
Abstract:
The use of internal curing is a highly effective means
of mitigating autogenous shrinkage in cement mortars
(w/s=0.35, 8% silica fume). Two different sources of
internal water supply are compared: 1) replacement of a
portion of the sand by saturated low-density fine
aggregate and 2) the addition of superabsorbent polymer
particles (SAP). At equal water addition rates, the SAP
system is seen to be more efficient in reducing
autogenous shrinkage at later ages, most likely due to a
more homogeneous distribution of the extra curing water
within the three-dimensional mortar microstructure. A
comparison of the water distribution in the different
systems, based on computer modeling and direct
observation of two-dimensional cross sections, is given.
