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Autogenous Healing of Early-Age Cracks in Cementitious Materials by Superabsorbent Polymers.

ABSTRACT: The effect of superabsorbent polymers (SAPs) on autogenous crack healing in cementitious materials with early-age cracking was investigated. SAP-containing samples exposed to wet/dry cycles showed better autogenous healing than those only exposed to wet conditions, as determined by water flow and compressive strength recovery tests. The water flow rates through cracks (380 ± 40 µm) in cement paste and cement mortar containing 1.0% SAP decreased by around 97.1-100% and 79.7-90.7%, respectively, after 14 cycles of healing compared to 1 cycle. Although the initial compressive strength decreased with SAP addition, it recovered somewhat after a 28-d healing period. Microscopy and spectroscopy results identified CaCO3 and/or calcium silicate hydrate (CSH) as the main healing products.

SUBMITTER: Hong G

PROVIDER: S-EPMC7040729 | BioStudies | 2020-01-01

SECONDARY ACCESSION(S): 10.1617/s11527-017-1053-3

REPOSITORIES: biostudies

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