Bernhard Elsener - University of Cagliari (original) (raw)
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Papers by Bernhard Elsener
Corrosion of Reinforcement in Concrete — Monitoring, Prevention and Rehabilitation
Corrosion of reinforcing steel represents the most widespread form of deterioration of concrete s... more Corrosion of reinforcing steel represents the most widespread form of deterioration of concrete structures resulting in significant costs for repair and replacement worldwide. Despite the huge demand, a simple, cheap and reliable technique that either protects the steel in concrete from corrosion or at least lowers its corrosion rate is still lacking. The concrete repair industry has developed novel techniques that are claimed to prevent the steel from corrosion and/or to restore the protective character of the cover concrete by introducing corrosion inhibitors into the carbonated or chloride contaminated concrete. Inhibitors, chemical substances that prevent or retard corrosion, are applied as concrete admixtures or as surface applied liquids both for preventive or for restorative applications. A short review on literature results regarding the performance of the most frequently used inhibitors for steel in concrete in laboratory and in field tests is given, in particular two inorganic inhibitors, calcium nitrite (DCI) and MFP, and several organic inhibitors, the "migrating inhibitors" (MCI or SIKA) and an organic corrosion-inhibiting admixture (OCI) are adressed. The problem of transport of inhibitors into concrete is discussed. A critical review of corrosion inhibitors to be used on reinforced concrete structures regarding concentration dependance, durability and measurement and control of the inhibitor action is given.
Materials and Structures, May 1, 2022
The steel-concrete interface (SCI) is a complex, multi-phase and multi-scale system. It is widely... more The steel-concrete interface (SCI) is a complex, multi-phase and multi-scale system. It is widely known to influence the performance and longterm durability of concrete structures. However, a fundamental understanding of its properties and effects on corrosion initiation of embedded reinforcing steel remains elusive. This is attributed to its complicated heterogeneity and time-dependent nature, exacerbated by the lack of suitable techniques for systematic and detailed characterisation. This paper, prepared by members of the RILEM Technical Committee 262-SCI, critically reviews available information regarding current methods (laboratory or field-based) for characterising local properties of the SCI that have been identified as governing factors affecting corrosion initiation. These properties include characteristics of the steel such as mill scale and rust layers, and characteristics of the concrete such as interfacial voids, microstructure and moisture content. We evaluated over twenty methods and summarised This article has been prepared within a framework of RILEM TC 262-SCI. The article has been reviewed and approved by all TC members. TC Membership.
Potentialfeldmessroboter für die Bauwerksinspektion – Automatisierte Erfassung des Korrosionszustandes von Stahlbetontragwerken
A data collection of critical chloride contents for steel corrosion in concrete
Monitoring chloride concentrations in concrete by means of Ag/AgCl ion-selective electrodes
Transport Processes in Concrete
Materials and Corrosion-werkstoffe Und Korrosion, Sep 4, 2017
A pH sensor to be used in highly alkaline media under continuous long-term immersion conditions i... more A pH sensor to be used in highly alkaline media under continuous long-term immersion conditions is crucial in various engineering applications. This work develops the production protocol and posterior conditioning of thermally oxidized iridium (IrOx) electrodes to be used as potentiometric pH sensors embedded in highly alkaline environments such as concrete or cathodically protected steel in soil. The main investigated aspects for the desired applications are the potential-pH response, its reproducibility, accuracy, and oxygen dependency. The stability during long-term immersion is also studied in detail. The studied IrOx electrodes responded to pH changes with slopes between-50 and-68 mV/pH unit, even after continuous immersion in alkaline solutions for almost 2 years. Additionally, the electrodes response did not show oxygen dependency. Our results highlight the importance of sufficient conditioning in alkaline media prior to use. When properly produced, conditioned, and pre-calibrated the electrodes reproducibly permit measuring the pH with a maximum error of 0.5 pH units over a range of at least pH 9 to 13.5. Preliminary results show that the studied electrodes are promising sensors for monitoring pH changes in concrete.
Characterisation of Surface Films on FeCrPC Alloys by XPS and X-ray Excited Auger Peaks
CRC Press eBooks, May 31, 2023
Passive films on Glassy FeCrPC Alloy—The Role of Phosphorus in Stability
CRC Press eBooks, May 31, 2023
Surface Analysis of Passive Films on Stainless Steels
Electrochemical Techniques
Potenzialmessung an Stahlbetonbauten
IEEE Transactions on Evolutionary Computation, 2013
Stray-Current-Induced Corrosion
Principles and Methods for Repair
Corrosion-Resistant Reinforcement
Chloride-Induced Corrosion
Carbonation-Induced Corrosion
Effect of reinforcement corrosion on serviceability behavior of RC beams and analytical model
Corrosion of Reinforcement in Concrete — Monitoring, Prevention and Rehabilitation
Corrosion of reinforcing steel represents the most widespread form of deterioration of concrete s... more Corrosion of reinforcing steel represents the most widespread form of deterioration of concrete structures resulting in significant costs for repair and replacement worldwide. Despite the huge demand, a simple, cheap and reliable technique that either protects the steel in concrete from corrosion or at least lowers its corrosion rate is still lacking. The concrete repair industry has developed novel techniques that are claimed to prevent the steel from corrosion and/or to restore the protective character of the cover concrete by introducing corrosion inhibitors into the carbonated or chloride contaminated concrete. Inhibitors, chemical substances that prevent or retard corrosion, are applied as concrete admixtures or as surface applied liquids both for preventive or for restorative applications. A short review on literature results regarding the performance of the most frequently used inhibitors for steel in concrete in laboratory and in field tests is given, in particular two inorganic inhibitors, calcium nitrite (DCI) and MFP, and several organic inhibitors, the "migrating inhibitors" (MCI or SIKA) and an organic corrosion-inhibiting admixture (OCI) are adressed. The problem of transport of inhibitors into concrete is discussed. A critical review of corrosion inhibitors to be used on reinforced concrete structures regarding concentration dependance, durability and measurement and control of the inhibitor action is given.
Materials and Structures, May 1, 2022
The steel-concrete interface (SCI) is a complex, multi-phase and multi-scale system. It is widely... more The steel-concrete interface (SCI) is a complex, multi-phase and multi-scale system. It is widely known to influence the performance and longterm durability of concrete structures. However, a fundamental understanding of its properties and effects on corrosion initiation of embedded reinforcing steel remains elusive. This is attributed to its complicated heterogeneity and time-dependent nature, exacerbated by the lack of suitable techniques for systematic and detailed characterisation. This paper, prepared by members of the RILEM Technical Committee 262-SCI, critically reviews available information regarding current methods (laboratory or field-based) for characterising local properties of the SCI that have been identified as governing factors affecting corrosion initiation. These properties include characteristics of the steel such as mill scale and rust layers, and characteristics of the concrete such as interfacial voids, microstructure and moisture content. We evaluated over twenty methods and summarised This article has been prepared within a framework of RILEM TC 262-SCI. The article has been reviewed and approved by all TC members. TC Membership.
Potentialfeldmessroboter für die Bauwerksinspektion – Automatisierte Erfassung des Korrosionszustandes von Stahlbetontragwerken
A data collection of critical chloride contents for steel corrosion in concrete
Monitoring chloride concentrations in concrete by means of Ag/AgCl ion-selective electrodes
Transport Processes in Concrete
Materials and Corrosion-werkstoffe Und Korrosion, Sep 4, 2017
A pH sensor to be used in highly alkaline media under continuous long-term immersion conditions i... more A pH sensor to be used in highly alkaline media under continuous long-term immersion conditions is crucial in various engineering applications. This work develops the production protocol and posterior conditioning of thermally oxidized iridium (IrOx) electrodes to be used as potentiometric pH sensors embedded in highly alkaline environments such as concrete or cathodically protected steel in soil. The main investigated aspects for the desired applications are the potential-pH response, its reproducibility, accuracy, and oxygen dependency. The stability during long-term immersion is also studied in detail. The studied IrOx electrodes responded to pH changes with slopes between-50 and-68 mV/pH unit, even after continuous immersion in alkaline solutions for almost 2 years. Additionally, the electrodes response did not show oxygen dependency. Our results highlight the importance of sufficient conditioning in alkaline media prior to use. When properly produced, conditioned, and pre-calibrated the electrodes reproducibly permit measuring the pH with a maximum error of 0.5 pH units over a range of at least pH 9 to 13.5. Preliminary results show that the studied electrodes are promising sensors for monitoring pH changes in concrete.
Characterisation of Surface Films on FeCrPC Alloys by XPS and X-ray Excited Auger Peaks
CRC Press eBooks, May 31, 2023
Passive films on Glassy FeCrPC Alloy—The Role of Phosphorus in Stability
CRC Press eBooks, May 31, 2023
Surface Analysis of Passive Films on Stainless Steels
Electrochemical Techniques
Potenzialmessung an Stahlbetonbauten
IEEE Transactions on Evolutionary Computation, 2013
Stray-Current-Induced Corrosion
Principles and Methods for Repair
Corrosion-Resistant Reinforcement
Chloride-Induced Corrosion
Carbonation-Induced Corrosion
Effect of reinforcement corrosion on serviceability behavior of RC beams and analytical model