Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Evaluation of an Embedded Wireless Relative Humidity Probe for Monitoring Concrete Drying
In this study, wireless embedded relative humidity, RH, probes, developed by Electrotech Kalix AB, were evaluated in a laboratory setting. These RH-probes are designed to monitor the drying of concrete at construction sites in a Swedish climate. Two concrete slabs, each with a thickness of 100 mm, were fabricated, using two different concrete mixes, with water-to-cement (w/c) ratios of 0.6 and 0.4. Drying was monitored for approximately six months using these wireless RH-probes embedded in the concrete. This extended testing period is important, as the drying of a concrete slab is slow and may take longer than 6 months to reach the required RH-level.The performance of the RH-probes during temperature fluctuations was also studied. Given that such fluctuations commonly occur at construction sites, this parameter is crucial to include in the study. Consequently, the ambient setpoint temperature varied during the test period, although it was initially constant at +20°C. After 14 days of drying at constant ambient conditions, two five- day periods were employed, separated by a five-day period at +20°C. During the first period, the ambient temperature varied daily between +20°C and +6°C, “Summer case”, and during the second period, it varied between -5°C and +5°C, ”Winter case”. Such temperature variations are plausible in a Swedish climate. Lower temperatures also occur. At temperatures below +5°C, special winter measures are usually adopted to protect newly cast concrete slabs.The RH was successfully measured using wireless embedded RH-probes in two separate concrete specimens over a 6-month period. Calibration of RH-probes was made before embedding and after 71 and 182 days of embedment in the concrete. The data indicate that the sensors demonstrated exhibit a high degree of accuracy, with the average deviation between the generated RH and the recorded RH readings being less than 1% RH. Calibration results showed that linear regression could be applied within the tested RH range, allowing for pre-installation ...
Evaluation of an Embedded Wireless Relative Humidity Probe for Monitoring Concrete Drying
In this study, wireless embedded relative humidity, RH, probes, developed by Electrotech Kalix AB, were evaluated in a laboratory setting. These RH-probes are designed to monitor the drying of concrete at construction sites in a Swedish climate. Two concrete slabs, each with a thickness of 100 mm, were fabricated, using two different concrete mixes, with water-to-cement (w/c) ratios of 0.6 and 0.4. Drying was monitored for approximately six months using these wireless RH-probes embedded in the concrete. This extended testing period is important, as the drying of a concrete slab is slow and may take longer than 6 months to reach the required RH-level.The performance of the RH-probes during temperature fluctuations was also studied. Given that such fluctuations commonly occur at construction sites, this parameter is crucial to include in the study. Consequently, the ambient setpoint temperature varied during the test period, although it was initially constant at +20°C. After 14 days of drying at constant ambient conditions, two five- day periods were employed, separated by a five-day period at +20°C. During the first period, the ambient temperature varied daily between +20°C and +6°C, “Summer case”, and during the second period, it varied between -5°C and +5°C, ”Winter case”. Such temperature variations are plausible in a Swedish climate. Lower temperatures also occur. At temperatures below +5°C, special winter measures are usually adopted to protect newly cast concrete slabs.The RH was successfully measured using wireless embedded RH-probes in two separate concrete specimens over a 6-month period. Calibration of RH-probes was made before embedding and after 71 and 182 days of embedment in the concrete. The data indicate that the sensors demonstrated exhibit a high degree of accuracy, with the average deviation between the generated RH and the recorded RH readings being less than 1% RH. Calibration results showed that linear regression could be applied within the tested RH range, allowing for pre-installation ...
Evaluation of an Embedded Wireless Relative Humidity Probe for Monitoring Concrete Drying
Åhs, Magnus (Autor:in)
25.11.2024
TVBM; (3191) (2024)
Paper
Elektronische Ressource
Englisch
DDC:
690
Internal relative humidity and drying stress gradients in concrete
| British Library Online Contents | 2006
Internal relative humidity and drying stress gradients in concrete
| Springer Verlag | 2006
Internal relative humidity and drying stress gradients in concrete
| Online Contents | 2006
Internal relative humidity and drying stress gradients in concrete
| Online Contents | 2006
Drying and Measuring Relative Humidity of Concrete in Practice
| British Library Conference Proceedings | 1996