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In industrialized countries, most of the reinforced concrete (RC) structures and infrastructures have more than 40 years, since they were built around 1960 − 1980, and were designed for a service life of 50 years. Consequently, in the next years, the number of structures and infrastructures that will need to be repaired will steeply increase. Several techniques, characterized by a different durability, environmental impact and economic impact, are available for the repair of a reinforced concrete structure damaged by the corrosion of reinforcement. To help the designers in the choice of the most suitable one, a preliminary assessment of the condition of the structure is essential, aimed at diagnosing the causes of deterioration, the extent of damage, i.e. the extent of corroding reinforcement, and its evolution in time. An approach, with a wide consensus, for the evaluation of the extent of corroding reinforcement is available for carbonation-induced corrosion, whilst it is still lacking for chloride-induced corrosion. In this paper two approaches for the evaluation of the extent of corroding reinforcement for a RC structure subject to chloride-induced corrosion are presented and compared, showing similar results. These approaches can be useful to properly plan a restoration intervention as well as to assess the reliability of the recently proposed model for service life design. [ABSTRACT FROM AUTHOR]

Cr2O3 coatings were deposited on carbon steel through the flame spraying technique using two types of flames (neutral and oxidizing). The protective and morphological characteristics of the coatings were determined. The coatings had layer thickness values of 114 and 214µm for oxidizing and neutral samples, respectively. Porosity percentages of 4.5 % and 2.5 % were determined, where the neutral sample presented the greatest porosity due to the insufficient fusion of the oxide particles during the process, resulting in the formation of a heterogeneous and less compact layer. Microcracks and pores were found on the surface and cross-section of the coatings, due to the thermal expansion generated during the solidification process. The coating protective capacity was evaluated by electrochemical techniques over 672 hours in a 3.5 %wt NaCl saline solution. The results evidenced that the coatings manufactured with the oxidizing flame presented more corrosion resistance compared to those prepared with the neutral flame. The corrosion products were more evident in the neutral flame coatings, because of the diffusion mechanisms from the substrate to the surface coating through the interconnected pores. Finally, the wettability of the sodium chloride solution in the Cr2O3 coatings was measured by the contact angle technique, finding that the oxidizing flame coatings exhibited a higher angle contact value (64.8°) in contrast to the neutral flame coatings (35°). [ABSTRACT FROM AUTHOR]

Canisters with a cast iron insert for mechanical strength and a 50‐mm thick copper shell as corrosion protection are planned to be used for disposal of spent nuclear fuel in Sweden and Finland. Chloride can be considered "beneficial", as it promotes active dissolution of copper rather than passivation (which might result in pitting), but a high concentration of chloride in solution would increase the driving force for corrosion through the formation of soluble copper chloro complexes. Thermodynamic calculations are performed in this study with the PHREEQC software and three of its accompanying databases, and a comparison with experimental data is performed to select the database to be used when evaluating repository performance. The activity coefficient models are given special attention. For the assessment of chloride‐assisted corrosion of a KBS‐3 canister, chloride concentrations pessimistically up to 5 mol/kg are used (in Finland and Sweden, the groundwater and bentonite porewater chloride concentrations are not expected to exceed 1 mol/kg). The resulting copper solubilities are then considered in different mass transport cases. [ABSTRACT FROM AUTHOR]

Steel embedded in concrete is normally in a passive state against corrosion due to a thin iron oxide layer that forms on the steel surface and remains stable in the high alkaline environment of the concrete. This protective film must be destroyed (depassivation) and this can be mainly done in two ways: by the attack of chlorides on the steel (seawater, de-icing salt, unwashed sea sand, admixtures, etc.) or by carbonation. Corrosion inhibitors may be a good alternative to protection steel against corrosion due to its lower cost and easy application. Many researchers are inclined to use surface applied corrosion inhibitors and prefer to use the Cl–/inhibitor parameter as an indication of chloride inhibitor threshold level. The objective of this study was to fill the gap left by public research in developing methods of corrosion control of reinforcement in concrete by synthetic solutions to emulate concrete environment. Three inhibitors were distinguished as passivation inhibitors in real solution extract and synthetic. In this study, the tests with calcium nitrite (CNI), sodium monoflurophosphate (MFP) and ethanolamine-based inhibitors showed reductions in the overall rates of corrosion after the inhibitive treatments. [ABSTRACT FROM AUTHOR]

Repair of car park ceilings with cathodic corrosion protection: investigations on the cathodic protection with separation cracks A repair of parking structures according to the repair principle of the cathodic corrosion protection (CP) can be an economic and gentle possibility to sustainably increase the remaining service life of the structure. RC ceilings frequently show separation cracks with penetrating chloride‐containing water and pitting corrosion of the reinforcement on the underside of the ceiling. This raises the question for the expert planner whether a CP system applied to the upper side of the ceiling can safely protect the corroding reinforcement on the underside. In practice it has been shown that proof of sufficient protection for this application is not trivial. This question was thoroughly examined in laboratory tests at the Institute for Material and Building Research of Munich University of Applied Sciences and in an underground parking garage. In summary of the investigations, it can be shown that the proof of the protection of the rear reinforcement in the separation crack can only be provided in a few of the investigated cases with the CP‐system installed solely on the upper ceiling side. The 100 mV criterion stipulated normatively in DIN EN ISO 12696 is too conservative for the proof of protection. However, if the proof of the 100 mV criterion is not successful, then corrosion and protective current measurements on subsequently electrically separated reinforcement areas can be considered more suitable for the proof of protection. [ABSTRACT FROM AUTHOR]

Biomarkers are complex molecules derived from formerly living organisms such as bacteria, fungi, algae, plankton, lichens, mosses, ferns and other higher plants. Biomarker concentrations are relatively low in oil and due to the high stability of its chemical structures, they are archaeological witnesses to its formation and transformation process. Based on the qualitative and quantitative composition of the molecules, it is possible to know the degree of oil biodegradation, determination of depositional environmental conditions (such as marine, terrestrial, deltaic, or hypersaline environments) and the type of precursor organic matter in the source rock. In addition, it is possible to carry out environmental, forensic and behavioral studies of hydrocarbon reservoirs. The objective of the present work is to develop an analytical methodology to obtain the distribution of saturated terpanes and steranes biomarkers using combined gas chromatography-mass spectrometry. From the extracted ion chromatograms, the peaks of 37 compounds from the group of terpanes and 19 compounds from that of the steranes were identified and integrated. The distribution was determined with their characteristic fragment ions of m/z 191, m/z 217 and m/z 218. Repeatability, intermediate precision and relative standard deviations were lower than 5%, which shows that the results are in agreement with the quality criteria established for analogous chromatographic methods. [ABSTRACT FROM AUTHOR]

Atmospheric corrosion of carbon steel AISI-1018 was studied in a coastal zone of tropical climate of Cuba with the presence of technologies aimed at the oil extraction and refining in operation. Two outdoor exposure sites were placed in the study zone. Wooden racks with device for determination of aggressiveness agent's monthly and averages annual, a sensor for the measurement of relative humidity-temperature complex, as well as fifteen specimens of carbon steel AISI-1018 for determination of corrosion rate monthly and annual, were installed in each exposure site placed at distance from the sea of 70 and 50 m without shielding effect. Corrosivity category of the atmosphere estimated from the typical characterization of the atmospheric environment and from the indirect values of corrosion ratewas similarity to determine from the annual values of corrosion rate determined directly for carbon steel at the two exposure sites in the study zone. Corrosivity categories of the atmosphere determined was high (C4). The atmospheric corrosion of carbon steel is influenced not only by the wet deposition of sulfate ions, but also by the wet deposition of chloride ions at both exposure sites. The relative humidity-temperature complex had a higher influence on the atmospheric corrosion of carbon steel at the exposure site placed at a higher altitude on sea level in the study area. The effect of height on sea level also influenced in a different classification of the types of atmosphere between the two exposure sites. [ABSTRACT FROM AUTHOR]

Atmospheric corrosion of carbon steel was studied in the oil refinery of Havana, Cuba. Four exposure sites, three in outdoor exposure condition and one in indoor exposure condition were placed in the refinery during one year of study. Corrosivity categories of the atmosphere higher, C5 very high and CX extreme, were expected for atmosphere classified as industrialcoastal, industrial and industrial highly polluted, due to high deposition of sulfate ions. Equivalence between two ways of estimation of corrosivity categories of the atmosphere was demonstrated for the atmospheres classified in the outdoor exposure condition. The high deposition of sulfate ions higher than chlorides, bring as results difference between the category of estimation and determination for atmosphere classified as industrial and industrial highly polluted. The category high (C4) was estimated and medium (C3) was determined. However, for an atmosphere classified as industrial-coastal, where the deposition of chloride ions is higher without being higher than sulphate ions, there was equivalence between the two ways of estimation and determination high (C4) of aggressivity corrosion for outdoor exposure condition. The chloride deposition salts remain as the most influential factor in the atmospheric corrosion of carbon steel, demonstrated in this study, for an atmosphere classified as industrial highly polluted. For the indoor exposure condition, there was equivalence between the estimation and determination of aggressivity corrosion of the atmosphere high (IC4) in the refinery. The increase in RH is the most influential factor in the atmospheric corrosion of carbon steel. [ABSTRACT FROM AUTHOR]

The repair method 8.3 "Corrosion protection by increasing the electrical resistance" according to EN 1504 (or the repair principle W‐Cl according to the DAfStb directive "Protection and repair of concrete building materials") represents a technically and economically interesting method for the repair of chloride‐contaminated concrete components. The coating applied as part of the repair principle prevents further water absorption of the concrete and, due to its permeability to water vapor, allows the concrete to dehydrate. Over time, this leads to an increase in the electrolytic resistance and thus to a reduction in the rate of corrosion. The article deals with the basic principles underlying this repair principle, deals with the current regulatory situation, and shows the responsibility of the expert planner. Groundbreaking studies on the effectiveness of the repair principle were carried out by Prof. Raupach, to whom this article is dedicated, and are summarized in this paper. The objective of the new studies, which build on the aforementioned research, is to establish universally accepted application limits, for example, the level of the remaining chloride concentration, for the low‐risk use of this repair method. [ABSTRACT FROM AUTHOR]

With the implementation of the repair method "increasing the electrical resistivity by coating" (MR 8.3), no direct repassivation of the reinforcing steel is initially intended. The success of the repair is rather linked to the change of the corrosion‐relevant parameters over time. These include an increase in the concrete resistivity due to dehydration and gradual decrease in corrosion currents and driving voltages on the reinforcing steel. Within the scope of a research project funded by the German Research Foundation (DFG), application limits for the repair principle W‐Cl could be defined. The chloride content present in the concrete at the rebar is the significant limiting factor for the application. While the corrosion activity even with moderately dehydrated specimens under diffusion‐retarding coatings at chloride contents of 1 wt% Cl−/c is in the range of the passive current density, this cannot be generally determined for chloride contents of 2 wt% Cl−/c. The type of coating has a decisive influence on the dehydration of the concrete. For example, less dense concretes under a permeable coating (acrylic dispersion/OS 4) can dry out to such an extent that the passive current density is reached. With semipermeable coatings and the presence of high chloride contents of 2 wt% Cl−/c, the repair principle W‐Cl does not lead to success according to the available test results. [ABSTRACT FROM AUTHOR]

This DFG‐funded research project aimed to gain a better understanding of the mechanisms of the W‐Cl repair principle within the framework of fundamental investigations, to contribute to the creation of the necessary basis for a broader application of the repair principle in practice. The focus was on the development of a model to describe the chloride redistribution after the application of a system sealing surface protective coating. On the basis of Fick's second law of diffusion, a mathematical model with a self‐contained analytical solution was developed, with the help of which the chloride redistribution after application of a system sealing surface protective coating can be calculated under the idealized assumption of complete water saturation of the concrete. Furthermore, the influence of the dehydration of the concrete, expected as a result of the application of the repair principle W‐Cl, on the chloride redistribution was investigated. On the basis of laboratory tests and numerical simulations, material‐specific reduction functions were developed to quantify the relationship between the chloride diffusion coefficient and the ambient humidity. [ABSTRACT FROM AUTHOR]

The anticorrosion performance of industrial waste, coconut shell powder (CSP), on UNS N08904 austenitic stainless steel in 3.5 % NaCl medium was studied via potentiodynamic polarization, weight loss and scanning electron microscope equipped with energy dispersive X-ray spectroscopy (SEM/EDX) methods. The experimental results show that CSP inhibited the corrosion of stainless steel and inhibition efficiency value increased with the increase in concentration. Better performance at low CSP concentration was registered, while 8 g CSP was identified as an optimum concentration inhibiting the stainless steel corrosion. This was mainly ascribed to the formation of CSP on the stainless steel surface, suppressing the propagation of corrosion pits effectively. The morphology of the corrosion produced on the stainless steel surface was studied by scanning electron microscope (SEM) after weight loss tests. The SEM/EDX spectra confirm the formation of a protective film due to CSP adsorption on the surface of the stainless steel. The inhibitor performs through adsorption and follows Langmuir isotherm in the chloride solution. Therefore CSP is a potential corrosion inhibitor for UNS N08904 stainless steel subjected to sodium chloride environment. [ABSTRACT FROM AUTHOR]

• Cation type associated with chloride ions significantly affected compressive strength of concrete. • Boundary potentials of different zones of corrosion were obtained in presence of chloride salts and corrosion inhibitors. • Corrosion inhibitors influenced the effect of cation type of chloride salts on passivity of reinforcing steel. • Cation type associated with chloride ions affected free chloride ion and bound chloride ion concentrations. • Sodium nitrite was more effective in enhancing passivity of steel than di-Sodium hydrogen phosphate. In this research, effect of cation type of chloride salts on corrosion behaviour of steel was determined by potentiodynamic polarization test in concrete powder electrolyte solution in presence of corrosion inhibitors. Results showed that cation type of chloride salts not only affected compressive strength of concrete but also passivity of steel and chloride binding. The decreasing trend of bound chloride concentration was C B: CaCl 2 > C B: MgCl 2 > C B: NaCl. Formation of various compounds in concrete was confirmed through XRD and FTIR spectroscopy analyses. Sodium nitrite was more effective in enhancing passivity of steel than di-Sodium hydrogen phosphate. [ABSTRACT FROM AUTHOR]

Abstract The treatment of wastewater containing high concentration of inorganic salts has always been one of the focuses of environmental researchers. In this work, the effect of Cl− and SO 4 2− on the removal of Cd2+ from wastewater using Fe0-electrocoagulation (Fe0-EC) were investigated by evaluating the transformation of Fe mineral. The experimental results indicated that the removal of Cd2+ from wastewater was depended on the property of Fe minerals. The generation of sulfate green rust (GRSO 4) produced in the presence of SO 4 2− showed stronger adsorption than the chloride green rust (GRCl) for Cd2+, and GRSO 4 was obtained even in the mixture Cl− and SO 4 2− solutions, because Fe(II)–Fe(III) GRs (layered double hydroxides, LDHs) showed stronger affinity for divalent SO 4 2− than monovalent Cl−. High concentration of inorganic anions in wastewater resulted in the negative charged Fe flocs. High concentration of Cl− promoted the oxidation of Fe(II) to Fe(III) by chlorine–containing oxidants, and increased the proportion of Fe(III)/Fe(II) in Fe flocs, secondary Fe mineral magnetite (Fe 3 O 4) was formed because of the increase of pH. Therefore, the presence of GRSO 4 intermediate increased the Cd2+ removal by adsorption (coagulation and coprecipitation), and then the generated GRSO 4 were gradually transformed into lepidocrocite (γ–FeOOH) by oxygen from air. Finally, the parameter optimization were conducted by adjusting the ratio of Cl− and SO 4 2− (R C:S), current density (j), initial pH (pH i), initial Cd2+ concentration (C 0), and temperature (T 0). The removal efficiency of Cd2+ reached 99.5% after 10 min Fe0-EC under the optimal parameters: R C:S = 25:50 mmoL/mmol , j = 6 mA/cm2, pH i = 7–9, and T 0 = 40 °C. Highlights • The effect of Cl− and SO 4 2− ratios on the removal of Cd2+ was studied. • The generation and transformation of Fe mineral was investigated. • The generation of sulfate green rust favored the adsorption of Cd2+. • The optimal EC parameters for the Cd2+ removal were obtained. [ABSTRACT FROM AUTHOR]

Highlights • Zn–Al–NO 2 LDH is proposed as a controlled-release inhibitor for steel reinforcements in chloride-contaminated concrete. • The cumulative amount of nitrites released from LDH is sensitive to the chloride concentration in the solution. • Compared with NaNO 2 , Zn–Al–NO 2 LDH exhibit high long-term inhibiting performance. Abstract Zn–Al–NO 2 layered double hydroxide (LDH) is proposed as a controlled-release inhibitor for steel reinforcements in chloride-contaminated concrete. The cumulative amount of nitrite released from LDH is sensitive to the chloride concentration in the solution. Compared with NaNO 2 , Zn–Al–NO 2 LDH increased the chloride threshold value from 0.15 to 0.25 M and simultaneously decreased the critical [NO 2 −]/[Cl−] molar ratio from 0.09 to 0.02. In conclusion, the Zn–Al–NO 2 LDH exhibits considerably higher inhibiting performance due to the on-demand release of NO 2 –. [ABSTRACT FROM AUTHOR]

Abstract Reinforced concrete structures experience severe durability degradation when subjected to alkali–silica reaction (ASR) and chloride attack. A special electrochemical rehabilitation treatment, containing lithium compound anolyte, has been developed to drive lithium ions into concrete composites and remove chlorides simultaneously, for mitigating both the ASR-induced cracks and the chloride-induced reinforcing steel-bar/fiber corrosion. In this study, the efficiency of the impregnation of lithium ions and the removal of chloride ions through a specific electrochemical treatment is numerically evaluated, which results into the distribution profiles of all typical ionic species. A heterogeneous numerical model, which treats concrete as a three-phase composite, is presented to examine the response of inner structures, especially the interaction between active aggregates and lithium ions that are supposed to mitigate ASR. The ionic interaction between different species, binding and the electrochemical reaction at electrodes are also considered. Through a detailed modelling of multi-phase and multi-species, a systemic parametric analysis based on a series of significant factors during electrochemical treatment (e.g., current density, treatment time, temperature, cathode position and concentration of lithium solution) reveals some important tendencies of ionic electromigration in concrete structures, which are supposed to guide the field applications. [ABSTRACT FROM AUTHOR]

Seawater is a corrosive medium that adversely affects on the metallic structures. For that reason, it is often desirable to use some type of corrosion protection to extend the life of structures. The aim of this work was to examine the possibility of CuNi alloy protection in artificial seawater by four benzimidazole derivatives: 2-amino-5(6)nitrobenzimidazole, 2-amino-5-(6)-cyanobenzimidazole, 2-aminobenzimidazole, 2-amino-5(6)-(2-imidazolinyl)benzimidazole hydrochloride. The corrosion studies conducted by polarization measurements after 1 h of immersion in inhibitor solution showed that the most effective inhibitor is 2-amino-5(6)-nitrobenzimidazole. The electrochemical tests were also performed in time by the means of electrochemical impedance spectroscopy for the two most effective inhibitors. The surface of samples was analyzed by scanning electron microscopy and ATR-FTIR spectroscopy. It was concluded that the efficiency of studied inhibitors increases with prolonged exposure of the CuNi alloy to inhibitor solutions as well as with the increase of inhibitor concentration. [ABSTRACT FROM AUTHOR]

The aim of the presented research work is to analyze and numerically describe the time‐dependent anode kinetics of steel in cracked reinforced concrete, which is exposed to de‐icing salts for a short time (one winter period) before a concrete coating is applied. In experimental studies the mechanism of chloride induced macro cell corrosion is investigated by measuring essential corrosion parameters. Therein, the surface coating finally leads to a halt of macro cell current for all actively corroding samples. The anode kinetics is identified as the decisive control factor leading to a stop of corrosion. In order to transfer the laboratory results onto real component geometries, numerical methods are used. These require a detailed workup of the anodic reaction kinetics, since the time‐dependent characteristics of the anode, identified in the experimental program, must be taken into account in the numerical simulations. For this, specific integral polarization resistances (rpi,a) are determined as an adequate approach which also allow for an extrapolation of the anode kinetics beyond the experimental investigations. The main findings of the numerical study are that geometrical and electrochemical influences, except the driving potential, are eventually superimposed by increasing rpi,a. As in the experimental studies, rpi,a is again identified as the dominant control factor stopping corrosion. Anode kinetics of steel in cracked, shortly chloride contaminated and subsequently coated reinforced concrete is experimentally investigated and numerically described. A suitable numerical approach which also allows for an extrapolation of the anodic reaction beyond the experimental investigations is found. As in the experimental studies the anodic resistance is again identified as the dominant control factor stopping corrosion. [ABSTRACT FROM AUTHOR]

This study examined the effects of silica addition on electrochemical behavior of rebar in native pH 12.5 saturated solutions prepared by leaching of Portland Type-II cement, and in solutions reduced by CO2 to pH 9. Cyclic polarizations showed that at pH 12.5 the silica additive increased the threshold concentration required for pitting from 100 to 105mM, and from 0.3 mM to 0.5 mM at pH 9. Passivation kinetic exponents were consistently larger for solutions with either pH when silica was present. The silica additive provided the passive film with generally increased resistance and lower capacitance, as confirmed by electrochemical impedance spectroscopy. Charge carrier densities calculated from Mott-Schottky plots were on the order of 1020 (cm-3), increasing significantly after the passive film breakdown. Raman spectroscopy of rebar samples immersed in saturated cement solutions showed films predominantly composed of iron oxyhydroxides with a new shoulder attributed to amorphous silica. [ABSTRACT FROM AUTHOR]

This study contributes to the development of more sustainable systems to limit and adverse the environmental effects as well as the disintegration of artificial Portland cement (APC) concrete structures. In this context, experimental tests were carried out to develop sustainable binders using natural pozzolan (PZ) and perlite (P) with a relatively high cement substitution rate. A certain level of cement replacement with these pozzolans is very advantageous in terms of cost, energy efficiency, environmental benefits, as well as mechanical properties and durability. A number of important properties of concrete such as compressive strength, corrosion resistance, chloride penetration, sulphate resistance have been developed and noted here. The results obtained show that 10% and 20% of natural pozzolan improves the mechanical properties, and it is noted that 10% of the replacement of the cement by pozzolan and 10% of the perlite led to a reduction of the speed of NaCl corrosion. A larger replacement of pozzolan and perlite had a negative effect on corrosion. Finally, it should be noted that sulfate ions did not affect the corrosion. [ABSTRACT FROM AUTHOR]

The corrosion resistance of 4044 aluminum alloy (4044AL) in acid chloride and neutral chloride solutions at 0.25-1.75% NaCl concentration was studied with potentiodynamic polarization technique, optical microscopy and open-circuit potential measurement. Variation of Cl− ion concentration had limited influence on the corrosion rate values of 4044AL in both test solutions; however, the corrosion rate values of 4044AL in the acid chloride media are significantly higher than values obtained from the neutral chloride solution due to the combined debilitating action of SO42- and Cl− ions in the acid chloride. Passivation behavior in the acid chloride media was completely absent compared to the neutral chloride solution where the passivation range extended across wide potentials before breakdown at the transpassive regions of the polarization plot due to localized corrosion reactions. Significant cathodic potential shift of 4044AL polarization plots and open-circuit potential was observed after 0.25% NaCl in the neutral chloride solution signifying dominant cathodic electrochemical reactions associated with localized corrosion on the steel surface. Morphological representations of the corroded 4044AL surface from 0.25 to 1.75% NaCl concentration showed the presence of extensive pitting and intergranular corrosion on the alloy from the neutral solution compared to general surface deterioration and superficial localized corrosion on the alloy from the acid chloride media which corroborate the extended time it took the alloy to achieve thermodynamic stability in the neutral chloride solution. [ABSTRACT FROM AUTHOR]

Two full-scale beams with dimensions 3000 × 280 × 150 mm were exposed in a chloride chamber for 27 and 36 months. Corrosion of the reinforcement in the beams was accelerated by wetting and drying cycles. Two deep beams were taken from each full-scale beam. Loading tests were carried out on the four deep beams and loading-deflection curves and slip of tensile bars were recorded during the tests. Then, the cross-sectional loss in the tensile bars and diameter loss in the stirrups were examined. The results showed that corrosion distribution was not uniform along the tensile bars. The correlation between cross-sectional loss of steel bar and surface crack width was weak. Serious pitting corrosion on the tensile bars changed the failure mode of deep beams from shear to flexure. The failure mode of corroded deep beams depends not only on span to effective depth ratio and the degree of corrosion of the tensile bars but also on the corrosion degree of the stirrups. [ABSTRACT FROM AUTHOR]

Chloride ion is known to accelerate corrosion in numerous metallic systems, although it is not well understood why. Using first-principles methods, such as density functional theory, it is possible to directly compute the energy of adsorption for chloride, and, using a thermodynamic framework based on statistical mechanics, to predict the environmental conditions under which it may be anticipated that chloride could displace other ions (such as hydroxide, incipient oxide, or other potentially corrosion inhibiting species) from the bare metal and/or oxide surface. By reviewing the literature, as well as performing some original density functional theory calculations, the authors present in this work the dependence of the surface coverage for H 2 O, OH, O and Cl on the electrochemical potential, pH and chloride concentration for a number of metallic systems, including nickel, iron, magnesium and aluminum, to predict the fundamental surface processes that may related to the role of chloride in potentially interfering with processes such as repassivation and metal dissolution. It is found that under some conditions certain metals can possess zones of mutual stability where both chloride and hydroxide may be coadsorbed, whereas other metals appear to have intrinsic resistance to chloride adsorption. Variations among the available first-principles adsorption energies obtained from different sources indicate that uncertainty analysis is necessary moving forwards. An analogous approach could be taken to consider the interaction of chloride with clean and defective oxide and/or hydroxylated surfaces. [ABSTRACT FROM AUTHOR]

In this work, the performance of reinforced concrete (RC) beams corroded under various levels of sustained flexural loads was evaluated. A comparison was made regarding the effect of different accelerated corrosion techniques, i.e., galvanic method and artificial climate exposure method, on the corrosion characteristics and structural performance of loaded RC beams. The results show that, regardless of sustained loading, a unique strong linear relationship can be established between the average mass loss of corroded rebar and the maximum corrosion-induced crack width, for both accelerated corrosion techniques. The application of flexural loads during corrosion exacerbates the corrosion in the pure flexural zone and enlarges the spatial variation of corrosion levels in RC beams. However, neither the average mass loss ratio of corroded rebar nor the crack widths can be a reliable way to estimate the residual capacity of the beams. [ABSTRACT FROM AUTHOR]

Reliability of low power electrical contacts such as those in hearing aid battery-spring systems is a very critical aspect for the overall performance of the device. These systems are exposed to certain harsh environments like high humidity and elevated temperatures, and often in combination with high levels of salt from human perspiration and environmental pollutants. In addition, the design aspects of such systems often call for multi-material combinations of substrate and coatings for catering to various requirements such as electrical conductivity and wear resistance, which in turn enhance the susceptibility of these systems to galvanic corrosion. In this study, traditional behind-the-ear (BTE) hearing aid systems, which failed during service were analysed. Failure analysis was performed on the dome type battery-spring contact systems. The morphology of the contact areas was observed using scanning electron microscopy, and the compositional analysis of the corrosion products and contaminants was performed using energy dispersive X-ray spectroscopy. Wear track morphology was observed on the contact points, and the top coating on the dome was worn out exposing the substrate spring material. The obtained results were correlated to the underlying corrosion mechanism and the failure mode is presented. [ABSTRACT FROM AUTHOR]

The present study was done to find the probable causes of AISI316L structured packings (SPs) failure in a dewatering phenol tower. In this tower, the SPs would provide a high contact surface between streams to maximize and accelerate the distillation process. Increasing vibration of discharging pump showed that there were detached pieces of SPs in pump's strainer. During plant overhaul, corrosion inspection was done and some of the broken packings were gathered for further analysis. The samples were evaluated by visual observation, optical and scanning electron microscope. Transgranular cracks in packing sheets and screws, used for restraining layers of packing together, were seen. Energy-dispersive X-ray spectroscopy (EDS) of corrosion products on packing and the fracture surface of the screw was conducted. The results showed the occurrence of chloride stress corrosion cracking. Even though the chlorine contents of tower streams were low, it seemed that process fluids have been mal-distributed leading to the local concentration of the chlorine on SPs surface. In addition to chlorine, high working temperature and applied stress provided a favorable condition for stress corrosion cracking. [ABSTRACT FROM AUTHOR]

Estimation of depassivation time is a key issue in corrosion prevention. A method to get a probabilistic model from a deterministic one is presented and applied to three simple models: square root of time (SRT), error function (EF) and constant flux (CF) models. Probability distributions of the involved random variables are needed as input parameters. Experimental data have been obtained from a concrete structure exposed to the atmospheric marine environment. These data are analysed to obtain the probability distributions of chloride transport parameters: penetration velocity k (SRT model), diffusion coefficient D (EF and CF models), surface chloride concentration C S (EF model), and chloride ingress flux J (CF model). These distributions are used to calculate the depassivation time probability distributions according to the three models and the orientation of the samples respect to the sea. This allows to estimate depassivation time for a given depassivation probability. [ABSTRACT FROM AUTHOR]

The Waelz oxides (WO) obtained upon processing of zinc containing semi products in Waelz kilns are rich in impurities such as alkalines, chlorides and fluorides. After acid leaching of the WO chlorine and fluorine ions dissolve into the zinc electrolyte, causing corrosion of aluminum cathode and lead anode and sticking of the deposited zinc on the cathode. For normal production operation the WO must contain up to 1000 ppm chlorine and 100 ppm fluorine. In the present study the laboratory tests on alkaline scrubbing of zinc containing WO in sodium carbonate solutions are presented. The effect of sodium carbonate concentration, pulp density and test duration on the degree of fluorine and chlorine purification is investigated. Based on the conducted research it was established that at temperature 363 K, pulp density 300 g l-1, concentration of sodium carbonate 100 g l-1 and test duration 180 min, the final concentration of fluorine and chlorine in the treated WO is 90 and 220 ppm, respectively. WO with such concentration of impurities are appropriate for further processing for cathode zinc production. [ABSTRACT FROM AUTHOR]

This article introduces the program of experimental atmospheric corrosion test carried out on weathering steel bridges in the Czech Republic. Corrosion losses and average thickness of corrosion products are measured and evaluated within this program. Protective ability of corrosion products is evaluated using X-ray diffraction analysis. Special attention is paid to the surfaces exposed to leakage from a failed drainage system. The test results show that the corrosion losses on structural elements are significantly conditioned by the position and location of exposed surface within the structure. The results also indicate a high degree of correlation dependence between measured average thickness of corrosion products and corrosion loss. [ABSTRACT FROM AUTHOR]

Corrosion of steel bars in concrete is usually a slow electrochemical process which may need a long time before damage becomes visible in the reinforced concrete (RC). However, cracks provide quick access to chloride, oxygen and water into concrete and accelerate the corrosion process. Corrosion modelling is essential for structural design for a particular life span, or to inform decisions on repair of RC structures to reach or extend their service life. This paper reports experimental research results of accelerated chloride exposure of cracked reinforced strain hardening cement-based composite (R/SHCC) specimens for a period of one year. Based on these novel results, a corrosion model is proposed which incorporates crack width, crack spacing, free chloride content and cover depth. The model is shown to capture the corrosion results of cracked R/SHCC reported in this paper. [ABSTRACT FROM AUTHOR]

This investigation focuses on sodium biphosphate (Na 2 HPO 4 ) as corrosion inhibitor for construction steel. All the tests are carried out in a solution that simulates the composition of the pores in chloride-contaminated carbonated concrete. The carbonated solution (CS) contained Na 2 CO 3 (0.0015 mol L −1 ), NaHCO 3 (0.03 mol L −1 ) and NaCl (0.1 mol L −1 ), resulting in [Cl − ]/[OH − ]=10000. Inhibited solutions (IS20, IS60 and IS100) incorporated 20, 60, and 100 mmol L −1 Na 2 HPO 4 respectively. These were labeled IS20, IS60 and IS100 respectively and result in [HPO 4 2− ]/[Cl − ] = 0.2, 0.6, and 1. Cyclic voltammograms and anodic polarization curves were complemented with micro-Raman spectroscopy and XPS, to evaluate the surface film composition. The results show that chloride contamination promotes active corrosion. When phosphate ions are incorporated, steel becomes passive with a more positive corrosion potential (Ecorr), and pitting presents as the predominant form of localized corrosion. Raman spectra show a broad band, centred in 982 cm −1 , suggesting that phosphates incorporate to the passive film. Phosphates are also present in the corrosion products. The surface film becomes more protective to pitting for the highest biphosphate content. However, after pitting no repassivation was detected. After over one month in immersion, steel remains passive in the condition IS100, with inhibition efficiency higher than 99%. In contrast, in the case of IS60 and IS20, pitting was detected. It can be concluded that phosphate ions are good candidates to be used as corrosion inhibitors for steel in chloride-contaminated concrete. [ABSTRACT FROM AUTHOR]

The purpose of this investigation is to analyze the effectiveness of phosphates as inhibiting agents for steel bars embedded in mortars. Three mix designs were selected for this study: mix A had no admixed chlorides and was used as reference; mix designs B and C were contaminated with 1% in weight of chlorides/weight of cement and mix C also incorporated 7% Na 3 PO 4 .12 H 2 O. After setting for 48 h, the samples were cured for 7 days immersed in water. Three specimens of each group were then immersed in aerated saline solutions 0.5 mol L −1 NaCl during 720 days. The corrosion potential ( Ecorr ), the polarization resistance ( Rp ) and the electrochemical impedance spectra were recorded regularly. After 720 days of immersion one set of mortars was anodically polarized and another set cathodically polarized. After that, Raman spectra of corrosion products were registered. Additional specimens were used to evaluate porosity and chloride profiles. The presence of phosphate ions as inhibitors has no effect on Ecorr values and suggests mixed-type inhibition. Mix C remains passive until 180 days of exposure, with Rt> 100 kΩ cm 2 . At longer times, Rt decreases in time but the inhibition percentage is always higher than 95% when evaluated by impedance spectra. Using Rp , inhibition stays above 70%. Anodic and cathodic polarization curves, together with corrosion potential values, suggest that phosphates behave as a mixed-type inhibitor. [ABSTRACT FROM AUTHOR]

In the present study, the corrosion risk of steel fibre in concrete was assessed by measuring the corrosion rate of steel fibre in chloride-contaminated mortar. Simultaneously, the rate of chloride transport in steel fibre mortar was determined by chloride profiles. Then, the interface of the steel fibre was examined by the scanning electron microscopy to ensure the porosity in the vicinity. As a result, it was found that the corrosion resistance of steel fibre against chloride was slightly higher than for reinforcing steel rebar in concrete, presumably due to the presence of mille scale on the surface; the chloride threshold level ranged 0.8–1.0% by weight of cement. However, transport of chloride ions in concrete containing steel fibre was accelerated by increased porosities in the vicinity of steel fibre, implying that external aggressive ions may easily penetrate the concrete then to chemically degrade concrete properties. In fact, the diffusion coefficient of chloride in mortar containing steel fibre ranged 4.79–9.61 × 10 −12 m 2 /s, as being 2–3 times higher for steel fibre-free mortar. [ABSTRACT FROM AUTHOR]

A severe leak occurred on the heat-exchanger tubes of a reboiler after approximately 9-month operation in the waste water stripping tower of a petrochemical plant. Failure analyses were carried out through the morphology observation and the chemical composition analysis of the corrosion products and water sample with optical microscopy, scanning electron microscopy, and X-ray diffraction techniques. The results reveal that the main compositions of the corrosion products are iron oxide, small amount of iron hydroxide, and iron silicate. Moreover, wall thinning and perforation obviously originated from the outer surface of the tube. Chloride ions play a catalysis role in accelerating the electrochemical corrosion. Some suggestions are proposed to alleviate and prevent the corrosion. [ABSTRACT FROM AUTHOR]

Marine environment is one of the most aggressive exposure conditions for concrete structures. The paper presents a probabilistic evaluation of corrosion initiation time of 80-month-old concrete structures under tropical marine environment with optimization method and Monte Carlo simulations. Results indicate that concrete cover depth and diffusion coefficient obey normal distribution and lognormal distribution, respectively. With target probability of failure value of 10%, corrosion initiation time is about 40 years after completion of construction. Compared with Monte Carlo simulations, optimization algorithm is an efficient method applied to the problem of chloride diffusion taking into consideration the time-dependent property of chloride diffusion coefficient. Sensitivity analysis should consider the influence of distribution and coefficient of variation of random variables. [ABSTRACT FROM AUTHOR]

In this study, the corrosion behavior of single crystalline MgO surfaces in simulated body fluid (SBF) is investigated. The corrosion mechanism and the nucleation and growth of surface layers relevant for biomineralization was studied by means of in situ atomic force microscopy (AFM) and complemented with X-ray photoelectron spectroscopy (XPS). At initial immersion stages, the dissolution of the surface dominates the overall corrosion behavior whereas biomineralization becomes relevant at later stages. Square etch pits are observed for the first time at the physiological pH-value. The results are discussed in terms of delicate interplay between the dissolution and growth of surface layers. [ABSTRACT FROM AUTHOR]

This paper discusses the effect of corrosion on the load-bearing capacity and ultimate deflection of corroded beams exposed to wetting–drying cycles in a chloride environment under sustained loading without impressed current. The mechanical performance of one control beam and two corroded beams was tested. Corroded bars in the beams were extracted for tensile tests and the cross-sectional losses were measured. The experimental results were compared with those obtained in a previous long-term aging program in a chloride environment. The experimental results confirmed that corrosion of the reinforcements modified the failure mode of reinforced concrete beams. The control beam failed due to crushing of the concrete in the compressive zone, while deteriorated beams failed due to the rupture of one tensile bar. As a result, the maximum cross-sectional loss on tension bars allows the residual yielding and ultimate capacity to be predicted since 1% reduction in cross-section corresponds to 1% reduction in yielding capacity and ultimate capacity. The results also show the importance of the initial ductility of the steel bars. Corrosion leads to more brittle behavior of steel bars in tension but the influence of corrosion on the ductility of RC beams depends on the initial ductility of the steel bar. In consequence, highly ductile steel bars belonging to Class C according to Eurocode 2 could prevent brittle collapse of corroded RC beams because of sufficient residual ductility of the corroded steel bars. [ABSTRACT FROM AUTHOR]

The microstructure of a gravity-cast A356 aluminium alloy modified with 0.4 wt% Nd and its corrosion behaviour in 3.5 wt% NaCl solution is investigated. The addition of Nd refines the eutectic silicon and results in the formation of Nd-containing intermetallics, which show smaller potential differences relative to the α-Al matrix than the Fe-rich intermetallics in the unmodified alloy. In 3.5 wt% NaCl solution, A356 and A356Nd alloys reveal localized corrosion attack at the Fe-rich/α-Al interfaces, which is then followed by localized corrosion through the eutectic areas. A more refined microstructure and the presence of Nd-rich phases in the A356Nd alloy considerably improves its pitting corrosion resistance compared with the A356 alloy which shows severe pitting corrosion. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the effectiveness of kelp extract as a corrosion inhibitor to resist the steel corrosion in mortars. The solvent extraction methods with several technologies were applied to prepare the kelp extracts, and their inhibiting efficacies were compared in the saturated calcium hydroxide solution. Besides, the extract with the best inhibition effect in the solution was applied in mortars. Several electrochemical techniques, compressive strength and flexural strength tests and visual inspection of steel surface were performed. Results indicate that all the extracts have an ability of inhibiting the steel corrosion in the solution. In principle, they are classified as a mixed inhibitor. The extract prepared by using 0·1 mol L−1 NaOH as a solvent exhibits a good inhibition effect in mortars. However, it decreases the compressive strength and flexural strength of mortar. Accordingly, the kelp extract is suggested to be applied cautiously as an inhibitor in the reinforced concrete. [ABSTRACT FROM AUTHOR]

Die oberste niederländische Straßen- und Wasserbaubehörde (Rijkswaterstaat) hat im Hinblick auf die langfristige Instandhaltung ihrer Infrastruktureinrichtungen über 1500 Endverankerungsbereiche von Spannbetonbrückenträgern instandgesetzt und einer kathodischen Korrosionsschutzbehandlung (KKS) unterzogen. Die Endbereiche wiesen mäßige bis starke Schäden durch Bewehrungskorrosion auf. Verursacht wurde die Korrosion durch Chloride, die über undichte Fugen eingedrungen waren. Durch den kathodischen Korrosionsschutz konnte der fortschreitende Korrosionsprozess unterbunden werden. Damit wurde das Risiko einer weiteren Zustandsverschlechterung der Spannbetonträger und eines möglichen Bruchs der Spannglieder auf ein Mindestmaß reduziert. Letztlich konnte die Nutzungsdauer von 30 betrachteten Brücken um mehr als 20 Jahre verlängert werden. Der vorliegende Beitrag skizziert die gewählte Herangehensweise. Application of cathodic protection on 30 concrete bridges with pre-stressing steel: remaining service life extended with more than 20 years In view of long term maintenance of its infrastructure facilities the Dutch Highway Administration (Rijkswaterstaat) has repaired over 1.500 heads of prestressed beams and provided them with cathodic protection (CP). The heads of these beams showed moderate to severe damage due to reinforcement corrosion caused by the penetration of chlorides from leaking joints, which required adequate intervention on the short term. By means of cathodic protection the corrosion process has been halted, so that the risk of further degradation of the beams and possible failure of the pre-stressing steel tendons has been minimized. In addition, the concrete repairs in the chloride contaminated parts of the beams will be durable. [ABSTRACT FROM AUTHOR]

Der Zweck der im vorliegenden Beitrag beschriebenen Untersuchung bestand darin, die Betonstahlbewehrung und nach Möglichkeit auch die Spannglieder auf einer Fläche von insgesamt 8 000 m2 der oberen Brückenfahrbahn des Viadukts 'Viadotto Colle Isarco' an der Brennerautobahn mittels Potentialfeldmessungen auf Korrosionserscheinungen zu untersuchen. So wurden Zonen mit hoher Korrosionswahrscheinlichkeit ermittelt und anschließend durch Öffnen und Sandstrahlen inspiziert. Auf der Grundlage dieser Prüfungen konnte abgeschätzt werden, dass auf etwa 9 % der Gesamtfläche eine hohe Korrosionswahrscheinlichkeit in den Spanngliedern gegeben ist. Bei früheren Inspektionen sind bereits gebrochene Spannglieder festgestellt worden. Sämtliche Brüche wurden dabei im Gewindebereich der Verbindungsgelenke festgestellt. In den korrodierten Spanngliedern, die in den 'aktiven' Zonen abseits der Verbindungsgelenke lagen, wurden dagegen keine Brüche gefunden. Von den gebrochenen Spanngliedern wurden Proben genommen und zur metallurgischen Analyse ins Labor geschickt. Dabei wurden keine Anzeichen für eine Wasserstoffversprödung des verwendeten Stahls festgestellt. Die Brüche, die in den Spanngliedern bei früheren Inspektionen festgestellt worden sind, wurden höchstwahrscheinlich durch Zyklen mit höherer Belastungsermüdung durch Verkehrslasten in Kombination mit Korrosion aufgrund belastungsempfindlicher Verbindungsgelenke verursacht. Corrosion survey of the bridge deck 'Viadotto Colle Isarco'/'Autobahnbrücke Gossensaß' on the Motorway called 'Autostrada del Brennero' in North-Italy The scope of this corrosion survey was to detect and quantify zones with high corrosion probability of the normal reinforcement and if possible the prestressed tendons of a total of 8 000 m2 surface area of the upper bridge deck of the 'Viadotto Colle Isarco'. This viaduct is part of the A22 Motorway called 'Autostrada del Brennero' and lays 10 km's south of the Austrian-Italian border in Italian territory approximately 1 200 m high in the Alps. In case serious problems were found no recommendations were requested at this point of the survey due to the size and the structural complexity of the concrete structure. Zones with high probability of corrosion were identified by the potentials measured and inspected through scarification and sandblasting. Based on this verification it was estimated an approximate 9 % of the total surface area with high probability of corrosion in the prestressed tendons. This amount is based on adding up all measuring points with a potential being more negative than -450 mV divided by the total amount of measuring points. During previous inspections fractured prestressed tendons were found. All the fractures were found in the threaded region of the coupler joints but no fractures were found in corroded tendons laying in the 'active' zones away from the coupler joints. Samples taken from the fractured tendons were sent to the lab for metallurgical analysis and revealed no susceptibility for hydrogen embrittlement of the steel used which has a perlitic microstructure. Fractures found in the tendons in previous inspections are most probably caused by major stress fatigue cycles from traffic loads in combination with corrosion due to the stress-sensitive couplings. Exactly similar cases (Heerdter crossing in Düsseldorf in 1976) were found in old reports, e.g. published in the technical report 26 'Influence of material and processing on Stress Corrosion Cracking of prestressing steel - case studies' by the International Federation for Structural Concrete (fib) in Lausanne. [ABSTRACT FROM AUTHOR]

This paper provides a short summary of investigations that have focused on the occurrence of the phenomenon that is commonly referred to as atmospheric chloride-induced stress corrosion cracking (AISCC) in types 304L and 316L austenitic stainless steels; the materials from which storage containers for the UK's intermediate level nuclear waste are currently fabricated. A brief overview of the relationship between localised corrosion phenomena (pitting or crevice corrosion) and stress corrosion cracking from observations derived under conditions of immersion in chloride-containing environments is provided. The impact of environmental variables such as the relative humidity, temperature and chloride deposition density on the development of AISCC and potential difficulties in extrapolating data derived from laboratory investigations to an in-store situation are also discussed. Proposals for the development of laboratory protocols that may more accurately reflect behaviour in an actual storage situation, including the possibility of employing accelerated testing methods, are also briefly addressed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effect of pyrolysis glass fiber on the corrosion process of mortars was evaluated. [•] The physico-chemical properties of these mortars (PGF+OPC) have been investigated. [•] In samples with 5% and 10% PGF the corrosion rates is similar to that of OPC. [•] The 15% PGF favors the diffusion of chlorides and the corrosion process is eased. [•] An efficient way to reuse the PGF could be the construction sector. [Copyright &y& Elsevier]

The steel strands in posttensioned (PT) concrete systems are typically embedded inside cementitious grout for protection from the environment. However, strands not embedded in grout have been observed in PT systems. The exposed strand is susceptible to corrosion, and particularly the location where the strand protrudes from the grout (i.e., grout-air-steel interface) is more vulnerable to corrosion. Prediction of the tension capacity () of strands with such interfaces under various exposure conditions is necessary for structural assessment. This prediction could be accomplished by using the data from an experimental program that includes the exposure of strands to various corrosive environments and testing to determine the time-variant residual of these strands. However, these tests are cumbersome and expensive, especially when it is necessary to maintain very high tensile stress conditions during the exposure period to simulate the in-service stress conditions on the strands in PT systems. Similar investigations of unstressed single wires are simpler and less expensive. This paper presents an experimental investigation of the corrosion-induced losses in the of unstressed wires, unstressed strands, and stressed strands. Based on these data, this paper develops probabilistic models to predict the of unstressed wires with grout-air-steel interfaces and subjected to various moisture and chloride conditions. By using these models for wires and the experimental data on strands, two probabilistic models are then developed to predict the of stressed strands based on the of unstressed wires. The developed models can be used to determine the of strands with grout-air-steel interfaces subjected to various exposure conditions, provided the of corresponding wires under those conditions is estimated. [ABSTRACT FROM AUTHOR]

The present study concerns a development of calcium aluminate cement (CAC) concrete to enhance the durability against an externally chemically aggressive environment, in particular, chloride-induced corrosion. To evaluate the inhibition effect and concrete properties, CAC was partially mixed with ordinary Portland cement (OPC), ranging from 5% to 15%, as a binder. As a result, it was found that an increase in the CAC in binder resulted in a dramatic decrease in the setting time of fresh concrete. However, the compressive strength was lower, ranging about 20 MPa, while OPC indicated about 30-35 MPa at an equivalent age. When it comes to chloride transport, there was only marginal variation in the diffusivity of chloride ions. The corrosion resistance of CAC mixture was significantly enhanced: its chloride threshold level for corrosion initiation exceeded 3.0% by weight of binder, whilst OPC and CAC concrete indicated about 0.5%-1.0%. [ABSTRACT FROM AUTHOR]

Highlights: [•] We monitored mass loss in metals exposed to electrolyzed water. [•] Surface roughness tests were used to pinpoint areas of greatest corrosion. [•] Corrosion on metal surfaces is influenced by pH and chloride concentration. [•] Surfaces not submerged in chlorine sanitizers are most susceptible to corrosion. [ABSTRACT FROM AUTHOR]

Highlights: [•] Anticorrosive properties of the coating modified with Ce-enriched zeolite microparticles. [•] Adsorption of Cu2+ and Cl− on zeolite in response to release of Ce(III) by ion exchange process. [ABSTRACT FROM AUTHOR]

The long-term behavior of concrete structures has shown that their main cause of distress is reinforcement corrosion. One of the most punishing exposure conditions for concrete is a marine environment such as that found in the Persian Gulf. Reinforcement corrosion from diffusion of chloride ions is the main mechanism for deterioration under such conditions; it is found that chloride penetration and chloride-induced reinforcement corrosion rates can be very high, often leading to a reduced service life. This paper presents results of a study performed on a 40-year-old RC jetty structure in the Mahshahr Petrochemical Special Zone, Persian Gulf region that had suffered extensive deterioration from chloride-induced corrosion. Based on visual inspection as well as in situ and laboratory tests, it was strongly evident that the structure had not been designed and built under sufficient qualitative specifications. [ABSTRACT FROM AUTHOR]

Highlights: [•] Stainless steel components of a geothermal heating system failed prematurely. [•] Crack surfaces were brittle in appearance and were predominately transgranular. [•] Failure was determined to be caused by chloride induced stress corrosion cracking. [•] Subsequent failures may be avoided by informed alloy selection. [ABSTRACT FROM AUTHOR]