Monitoring Early-age Concrete with the Acoustic-emission Method and Determining the Change in the Electrical Properties

Monitoring Early-age Concrete with the Acoustic-emission Method and Determining the Change in the Electrical Properties

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Concrete is the most popular building composite material (CM). Its long-term aging properties depend on the mixture, the setting and the curing. When concrete is produced and used in the place where we want it to be for the whole of its life, it is very sensitive and easily ruined. Curing is one of the things that we do to keep concrete protected during the first week or so of its life: we maintain proper temperature (neither too hot nor too cold) and dampness. The acoustic-emission method and the electrical-property measurement technique are applied to monitor early-age concrete. The relationships between the acousticemission activity, the temperature and the electrical properties, e.g., the resistivity and the capacity of concrete at an early age were studied in this research. W. Chen et al. studied the microstructure development of hydrating cement pastes during early ages using non-destructive methods including the ultrasound P-wave propagation-velocity measurement and non-contact electrical-resistivity tests. Nevertheless, there are not many references about the continuous study of the properties of concrete during an early age. A long-time monitoring of concrete properties is necessary to determine its lifetime and quality. The acoustic-emission method was proven to be a very advantageous tool for a non-destructive monitoring of structural microchanges during the lifetime of concrete. The differences between hardened concrete mixtures detected with acoustic emission can partly determine their properties at the age of 28 d. The basic concrete property is its compressive strength after 28 d; nevertheless, this can change over a long time period, thus a continuous measuring needs to be applied.

Concrete is the most popular building composite material (CM). Its long-term aging properties depend on the mixture, the setting and the curing. When concrete is produced and used in the place where we want it to be for the whole of its life, it is very sensitive and easily ruined. Curing is one of the things that we do to keep concrete protected during the first week or so of its life: we maintain proper temperature (neither too hot nor too cold) and dampness. The acoustic-emission method and the electrical-property measurement technique are applied to monitor early-age concrete. The relationships between the acousticemission activity, the temperature and the electrical properties, e.g., the resistivity and the capacity of concrete at an early age were studied in this research. W. Chen et al. studied the microstructure development of hydrating cement pastes during early ages using non-destructive methods including the ultrasound P-wave propagation-velocity measurement and non-contact electrical-resistivity tests. Nevertheless, there are not many references about the continuous study of the properties of concrete during an early age. A long-time monitoring of concrete properties is necessary to determine its lifetime and quality. The acoustic-emission method was proven to be a very advantageous tool for a non-destructive monitoring of structural microchanges during the lifetime of concrete. The differences between hardened concrete mixtures detected with acoustic emission can partly determine their properties at the age of 28 d. The basic concrete property is its compressive strength after 28 d; nevertheless, this can change over a long time period, thus a continuous measuring needs to be applied.