Probing the microstructure of cement mortars through dielectric parameters‟ variation

dc.contributor.author	Τσώνος, Χρήστος	el
dc.contributor.author	Σταύρακας, Ηλίας	el
dc.contributor.author	Αναστασιάδης, Κίμων	el
dc.contributor.author	Κυριαζόπουλος, Αντώνης	el
dc.contributor.author	Καναπίτσας, Αθανάσιος	el
dc.date.accessioned	2015-04-04T21:45:52Z
dc.date.available	2015-04-04T21:45:52Z
dc.date.issued	2015-04-05
dc.identifier.uri	http://hdl.handle.net/11400/8233
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://www.elsevier.com	en
dc.subject	A. Microporous materials
dc.subject	D. Dielectric properties
dc.subject	D. Electrical conductivity
dc.subject	D. Electrical properties
dc.subject	D. Microstructure
dc.subject	Α μικροπορώδη υλικά
dc.subject	Δ διηλεκτρικές ιδιότητες
dc.subject	Δ Ηλεκτρική αγωγιμότητα
dc.subject	Δ Ηλεκτρικές ιδιότητες
dc.subject	Δ μικροδομή
dc.title	Probing the microstructure of cement mortars through dielectric parameters‟ variation	en
heal.type	journalArticle
heal.classification	Technology
heal.classification	Engineering
heal.classification	Τεχνολογία
heal.classification	Μηχανική
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh85133147
heal.classificationURI	http://zbw.eu/stw/descriptor/19795-3
heal.classificationURI	N/A-Τεχνολογία
heal.classificationURI	N/A-Μηχανική
heal.contributorName	Τριάντης, Δήμος Α.	el
heal.identifier.secondary	doi:10.1016/j.jpcs.2008.12.015
heal.language	en
heal.access	free
heal.publicationDate	2009-03
heal.bibliographicCitation	TSONOS, C., STAVRAKAS, I., ANASTASIADIS, C., KYRIAZOPOULOS, A., KANAPITSAS, A. ET AL. (2009). Probing the microstructure of cement mortars through dielectric parameters’ variation. Journal of Physics and Chemistry of Solids. [Online] 70 (3-4). p.576-583. Available from: http://www.sciencedirect.com/ [Accessed 30/12/2008]	en
heal.abstract	The present work deals with the electrical properties of typical cement mortars during the hardening process, cured at low relative humidity. Measurements were made by using dielectric spectroscopy (DS) over a broad frequency range of 10 Hz–1 MHz and isothermal depolarization current (IDC) techniques, for several weeks after sample preparation. This work presents a coherent study of the various formalisms employed in dielectric spectroscopy. Each of these formalisms contributes to the development of the complete relaxation mechanisms that are responsible for the frequency spectrum. After the first week of hardening, when the DC conductivity effects were absent, two distinct dielectric relaxation mechanisms were observed in the frequency spectrum of the complex permittivity ε* and tan δ functions. The mechanism positioned at low-frequency region (few kHz) is observed for the first time, as we know from the literature, on cement mortars. The relaxation times of both mechanisms were found to increase gradually, while the strength of the relaxation mechanisms varied also as a function of the hardening time. Fitting analysis in complex impedance Z* and electric modulus M* formalisms revealed also the existence of two short-range relaxation mechanisms of conductivity. We suggest that the low-frequency relaxation is related to the closed capillary pores and the high-frequency relaxation to the C-S-H gel pores. An increase of the mean dimension, of both types of pores, estimated from our data analysis with hardening time.	en
heal.publisher	Elsevier	en
heal.journalName	Journal of Physics and Chemistry of Solids	en
heal.journalType	peer-reviewed
heal.fullTextAvailability	true