eprintid: 9631
rev_number: 2
eprint_status: archive
userid: 1
dir: disk0/00/00/96/31
datestamp: 2023-11-09 16:36:16
lastmod: 2023-11-09 16:36:16
status_changed: 2023-11-09 16:29:27
type: article
metadata_visibility: show
creators_name: Malkawi, A.B.
creators_name: Al-Mattarneh, H.
creators_name: Achara, B.E.
creators_name: Muhammed, B.S.
creators_name: Nuruddin, M.F.
title: Dielectric properties for characterization of fly ash-based geopolymer binders
ispublished: pub
keywords: Dielectric losses; Dielectric materials; Dielectric properties; Fly ash; Geopolymers; Hardening; Inorganic polymers; Permittivity; Porosity; Regression analysis; Silicates; Sodium hydroxide, Alkaline solutions; Dielectric loss factors; Geopolymer binders; Loss factor; Parallel plate capacitors; Quality control applications; Setting time; Sodium hydroxide solutions, Binders
note: cited By 23
abstract: In this study, a method for determining the setting time and the porosity of fly ash-based geopolymer binders (FAGPBs) has been established. This method permits a real-time monitoring of the geopolymerisation and hardening progressions. A parallel plate capacitor cell technique was used to determine the dielectric constant εr ' and dielectric loss factor εr '' of fresh and hardened mixes. Equivalent model-circuits of the measurement system were developed, and the accuracy of the system was verified. The dielectric properties were monitored at different ages until 56 days over a frequency range of 0.1�60 MHz. The alkaline solution to fly ash ratio, sodium silicate to alkaline solution ratio, and sodium hydroxide solution molarity were varied to study their effects on the dielectric properties. It was found that dielectric properties can provide valuable information when measured in the frequency range of 10�25 MHz. In this range, the dielectric values responded well to the variations with age and with mix properties. The relationships between the dielectric properties and the different physical states and constituent materials of FAGPBs could be used for quality control applications. The εr ' and εr '' time plots were effectively utilized to determine the setting time and the rate of geopolymerisation of FAGPBs. Measurements showed a strong correlation between εr ' and porosity; the εr ' values decreased 2.3-fold over a porosity range of 3�15. The proposed regression models can be further used in determining the porosity of FAGPBs at a high accuracy level. © 2018 Elsevier Ltd
date: 2018
publisher: Elsevier Ltd
official_url: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85052903651&doi=10.1016%2fj.conbuildmat.2018.08.180&partnerID=40&md5=e1352be8a10319340889185b94c699a0
id_number: 10.1016/j.conbuildmat.2018.08.180
full_text_status: none
publication: Construction and Building Materials
volume: 189
pagerange: 19-32
refereed: TRUE
issn: 09500618
citation:   Malkawi, A.B. and Al-Mattarneh, H. and Achara, B.E. and Muhammed, B.S. and Nuruddin, M.F.  (2018) Dielectric properties for characterization of fly ash-based geopolymer binders.  Construction and Building Materials, 189.  pp. 19-32.  ISSN 09500618