The potential of conventional superabsorbent polymers (SAP) based on partially neutralised acrylate and acrylate/acrylamide copolymers as an admixture for self-sealing of cracks in concrete is investigated. SAP are crosslinked polymers that can absorb a disproportionately large amount of liquid and swell substantially to form a soft and insoluble gel. However, their swelling capacity is highly dependent on the alkalinity and ionic content of the solution. These characteristics may be exploited

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... or self-sealing cracks in concrete. In this preliminary study, the mechanism involved is described and tests performed to determine the swelling ratios of SAP in various solutions including synthetic pore solution, groundwater and seawater are reported. Transport testing found that the flow rate through a 340μm wide model crack is reduced substantially by using less than 1% vol. SAP. The re-swelling capacity of SAP in cement paste and the effect of SAP on cement paste microstructure were investigated by microscopy.