TY - JOUR
T1 - Observations of ice lens formation and frost heave in young Portland cement paste
AU - Corr, David J.
AU - Monteiro, Paulo J.M.
AU - Bastacky, Jacob
N1 - Funding Information:
The authors would like to thank Ms. Evelyn Clausnitzer of the Children's Hospital Oakland Research Institute for her assistance with the LTSEM analysis presented here. We would also like to recognize the National Science Foundation (NSF grant 442408-21202) and the California Tobacco-Related Disease Research Program (grant 4RT-0832) for their continued support of this research.
PY - 2003/10
Y1 - 2003/10
N2 - As part of a research program to image frozen cement past specimens, abnormal microstructural formations are seen in specimens frozen after 10-h hydration. The formations are areas of loose microstructure with aspect ratios of 6-10, which appear perpendicular to the direction of cooling in the specimen. After sublimation of the water in the specimens during the imaging process, these formations collapse, indicating that ice is instrumental to their structure. These formations coincide with longitudinal cracks in the specimen, which do not appear to be due to specimen preparation and are consistent with an internal tensile strain. The authors have hypothesized that ice lens formation and frost heave, or a similar freezing mechanism, is responsible for these microstructural features, which are seen in 10-h specimens and are absent in all other cement paste specimens. Triaxial permeability tests have also shown that the cement paste mix used in this study has a permeability at 10-h age of ~10-6 cm/s. This permeability is similar to that of silty soil, some of the most susceptible to frost heave.
AB - As part of a research program to image frozen cement past specimens, abnormal microstructural formations are seen in specimens frozen after 10-h hydration. The formations are areas of loose microstructure with aspect ratios of 6-10, which appear perpendicular to the direction of cooling in the specimen. After sublimation of the water in the specimens during the imaging process, these formations collapse, indicating that ice is instrumental to their structure. These formations coincide with longitudinal cracks in the specimen, which do not appear to be due to specimen preparation and are consistent with an internal tensile strain. The authors have hypothesized that ice lens formation and frost heave, or a similar freezing mechanism, is responsible for these microstructural features, which are seen in 10-h specimens and are absent in all other cement paste specimens. Triaxial permeability tests have also shown that the cement paste mix used in this study has a permeability at 10-h age of ~10-6 cm/s. This permeability is similar to that of silty soil, some of the most susceptible to frost heave.
KW - Freezing and thawing
KW - Frost heave
KW - Microstructure
KW - Permeability
KW - SEM
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U2 - 10.1016/S0008-8846(03)00103-0
DO - 10.1016/S0008-8846(03)00103-0
M3 - Article
AN - SCOPUS:0043195364
SN - 0008-8846
VL - 33
SP - 1531
EP - 1537
JO - Cement and Concrete Research
JF - Cement and Concrete Research
IS - 10
ER -