The drying process in concrete is very slow. Hygral gradients
exist for a long time in drying concrete elements with usual dimensions.
Measured shrinkage, is in fact the response of a concrete
specimen to strains and stresses generated by the drying process.
If the water loss of a specimen with known geometry is measured,
the Hygral diffusion coefficient can be determined by inverse analysis
[20].
Shrinkage is important in applications such as large slabs on
grade, containment structures, and reinforced concrete exposed
to deicing chemicals. Shrinkage of concrete on drying frequently
leads to cracking; this is recognized in concrete design and construction
practice, especially concerning pavements, floors, and
relatively thin structural members. To counteract this problem
shrinkage-compensating concrete containing expansive cements
or expansive admixtures has been employed successfully for the
last 20 years [21].