Real-Time Monitoring of Cement Paste Carbonation with In Situ Optical Fiber Sensors

• Type: Article in International Scientific Journal
• Date: 2023

Authors

da Silva, PM (Author) Other; Mendes, JP (Author) Other; Coelho, LCC (Author) FCUP; de Almeida, JMMM (Author) FCUP

Journal

The Journal is awaiting validation by the Administrative Services.

Title: CHEMOSENSORS

Vol. 23

Final page: 449

ISSN: 2227-9040

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 0 Citations

Other information

Authenticus ID: P-00Y-VZB

DOI: 10.3390/chemosensors11080449

Abstract (EN): Reinforced concrete structures are prevalent in infrastructure and are of significant economic and social importance to humanity. However, they are prone to decay from cement paste carbonation. pH sensors have been developed to monitor cement paste carbonation, but their adoption by the industry remains limited. This work introduces two new methods for monitoring cement paste carbonation in real time that have been validated through the accelerated carbonation of cement paste samples. Both configurations depart from traditional pH monitoring. In the first configuration, the carbonation depth of a cement paste sample is measured using two CO2 optical fiber sensors. One sensor is positioned on the surface of the sample, while the other is embedded in the middle. As the carbonation depth progresses and reaches the embedded CO2 sensor, the combined response of the sensors changes. In the second configuration, a multimode fiber is embedded within the paste, and its carbonation is monitored by observing the increase in reflected light intensity (1.6-18%) resulting from the formation of CaCO3. Its applicability in naturally occurring carbonation is tested at concentrations of 3.2% CO2, and the influence of water is positively evaluated; thus, this setup is suitable for real-world testing and applications.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 16