Mapping Drying Shrinkage Deformations in Cement-Based Materials.
Mapping Drying Shrinkage Deformations in Cement-Based
Neubauer, C. M.; Jennings, H. M.; Garboczi, E. J.
Cement and Concrete Research, Vol. 27, No. 10,
cements; deformation; digital images; finite elements;
A new technique for mapping the deformations in a
digital image of microstructure is presented. This
technique works on any set of two digital images of the
same area taken before and after deformations are
generated. Results for cement paste show that the
deformations are distributed as large compactions
separated by crack-like rarefactions. The rarefactions
may represent the precursor to microcracking. The
results suggest that macro-scale deformation is the
result of a competition between expanding and
contracting parts of the matrix. Individual
microdeformations can then be much higher in magnitude
than average macrodeformations. A single shrinkage
value like the average macrodeformation does not,
therefore, adequately represent the microstructural
processes occurring during drying shrinkage.