Searched for: author%3A%22Pargar%2C+F.%22
(1 - 14 of 14)
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Pargar, F. (author), Koleva, D.A. (author), van Breugel, K. (author)
In this paper the potentiometric response of a Ag/AgCl electrode as a chloride sensor in cementitious materials of different mix design was studied. The chloride sensor’s response was discussed with respect to the presence of hydration products around the sensor. The free chloride content inferred from the sensor’s response was compared to the...
journal article 2019
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Pargar, F. (author)
Determination of the chloride content in a reinforced concrete structure is important for evaluation of the risk of chloride-induced corrosion of reinforcement. The traditional techniques for chloride determination in concrete are laborious, time-consuming and cannot be used for continuous monitoring of the chloride content. The investigation on...
doctoral thesis 2018
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Pargar, F. (author), Kolev, H (author), Koleva, D.A. (author), van Breugel, K. (author)
The stability and reproducibility of an Ag/AgCl sensors’ response in an alkaline medium are important for the application of these sensors in cementitious materials. The sensors’ response, or their open circuit potential (OCP), reflects a dynamic equilibrium at the sensor/environment interface. The OCP response in an alkaline medium is affected...
journal article 2018
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Pargar, F. (author), Koleva, D.A. (author), van Breugel, K. (author)
Determination of the free chloride content in a concrete structure is important for evaluation of the risk of corrosion of reinforcing steel. The Ag/AgCl sensor is sensitive to chloride ions and exhibits an open circuit potential (OCP) that depends on the chloride ions activity in the environment. The interference of hydroxide and sulfide ions...
conference paper 2018
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Pargar, F. (author), Kolev, H (author), Koleva, D.A. (author), van Breugel, K. (author)
Characterization of the Ag/AgCl electrode is a necessary step toward its<br/>application as a chloride sensor in a highly alkaline medium, such as concrete.<br/>The nucleation and growth of AgCl on Ag in 0.1 M HCl was verified through<br/>cyclic voltammetry. Ag anodization was performed at current densities, determined<br/>by potentiodynamic...
journal article 2018
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Pargar, F. (author), Koleva, D.A. (author)
When studying chloride-induced corrosion in reinforced concrete structures, essential information of interest is the concentration of chloride ions in the system. The absence of a reliable method for monitoring the free chloride ions justifies the attempts towards establishing a feasible practice in the application of the already known Ag/AgCl...
journal article 2017
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Pargar, F. (author), Koleva, D.A. (author), van Breugel, K. (author)
This paper reports on the advantages and drawbacks of available test methods for the determination of chloride content in cementitious materials in general, and the application of Ag/AgCl chloride sensors in particular. The main factors that affect the reliability of a chloride sensor are presented. The thermodynamic behaviour of silver in the...
journal article 2017
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Pargar, F. (author), Koleva, D.A. (author), van Breugel, K. (author)
Free chloride ions are the main cause of steel corrosion in reinforced concrete structures. Ag/AgCl electrodes, as chloride sensors, are predominantly sensitive to chloride ions and respond electrochemically to the chloride ion activity in the environment. This is reflected by changes of the open circuit potential (OCP) of the sensors. To...
conference paper 2015
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Abbas, Y. (author), Pargar, F. (author), Olthuis, W. (author), Van den Berg, A. (author)
The half-cell potential of the Activated carbon (AC), due to its high double layer capacitance (EDL), remains stable in high ionic electrolyte. The open circuit potential (OCV) of the AC, with EDL of 40 – 50 F, shows a stable potential (10 mV variation) over two weeks in the cement pore solution (sat. Ca(OH)2). The OCV is less sensitive to the...
journal article 2014
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Pargar, F. (author), Koleva, D.A. (author), Koenders, E.A.B. (author), Van Breugel, K. (author)
One of the reported problems associated with the performance of Ag/AgCl electrodes in alkaline environment, as concrete pore water, has been their poor stability. Open circuit potentials are typically observed to be stable for a time period of a few minutes to some days depending on the thickness and microstructure of the sparingly soluble AgCl...
conference paper 2014
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Pargar, F. (author), Koleva, D.A. (author), Copuroglu, O. (author), Koenders, E.A.B. (author), van Breugel, K. (author)
The level of free chloride concentration in reinforced concrete structures essentially determines the onset of steel corrosion initiation and further propagation. One of the well-known methods for monitoring free chloride concentration is using silver/silver chloride electrodes (Ag/AgCl). These electrodes are sensitive mainly to chloride ions...
conference paper 2014
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Pargar, F. (author), Koleva, D.A. (author), Copuroglu, O. (author), Koenders, E.A.B. (author), van Breugel, K. (author)
The stability of chloride ion selective electrodes in highly alkaline solutions is an important aspect when reliability and feasibility within reinforced concrete applications are concerned. The sensitivity of these electrodes largely depends on the properties of the AgCl layer, including uniformity, porosity, orientation, thickness, etc. These...
conference paper 2014
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Pargar, F. (author), Koleva, D.A. (author), Koenders, E.A.B. (author), van Breugel, K. (author)
Service life of reinforced concrete structures exposed to chloride enriched environment is well known to be mainly determined by steel passivity breakdown in the event of chloride-induced corrosion initiation and propagation. Since Cl- induced (localized) corrosion is caused by the free (water-soluble) chloride, present in the pore network of a...
conference paper 2014
document
Abbas, Y. (author), Pargar, F. (author), Olthuis, W (author), van den Berg, A. (author)
The half-cell potential of the Activated carbon (AC), due to its high double layer capacitance (EDL), remains stable in high ionic electrolyte. The open circuit potential (OCV) of the AC, with EDL of 40 – 50 F, shows a stable potential (10 mV variation) over two weeks in the cement pore solution (sat. Ca(OH)2). The OCV is less sensitive to the...
conference paper 2014
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