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In corrosion science, accurate determination of chloride ion deposition rates is critical to mitigating the environmental impact on structures. Traditional methods, such as the wet candle and dry plate methods (ISO 9225), are often inaccurate in capturing localized conditions and are also time-consuming and costly. The Bresle method, which measures soluble salts directly on metal surfaces, offers a more targeted approach. This article examines the Bresle method as an alternative for determining average monthly chloride ion deposition rates, including a regression analysis comparing the Bresle method with the wet candle method, and examines the long-term salinity of exposed surfaces in comparison with the additive approach to surface salinity. This paper hypothesizes that the Bresle method can be used as an alternative to the wet candle method. Linear regression analysis shows a strong correlation in chloride ion deposition rates compared to those measured by the wet candle method. However, cumulative measurements using long-term exposed coupons are unreliable due to inconsistent trends. [ABSTRACT FROM AUTHOR]

There are numerous steel bridges worldwide, many of which are made from weathering steel. Trademarks of weathering steel, such as Corten (the United States), Atmofix (the Czech Republic), NAW‐TEN and CORSPACE (Japan), or Q345CNH (China) are commonly used. Inland steel bridges are impacted by chloride ions, primarily dispersed into the air by road traffic from de‐icing salt (NaCl) and brine solutions used in winter road maintenance, which can compromise the integrity of the bridges' load‐bearing structures. The quantity of deposited chlorides fluctuates based on the distance from the source, especially for inland bridges, where it is determined by the distance from the road. There is also a difference between the winter season and the rest of the year. The study presents in‐situ measurement data from two sites, analyzing the corrosion loss. Additionally, a regression analysis is conducted to understand the relationship between the distance from the road guide line and the corrosion loss. [ABSTRACT FROM AUTHOR]

Phenomenon of corrosion in structural materials is very important, because they very often yield to aggressive environment. Moreover, not inconsiderable effect of fatigue damage via cyclic loading of such engineering structures should be considered as well. Thus, the influence of a corrosion pit (of a circular segment shape) on the stress distribution in a rectangular specimen subjected to remote tensile stress range has been investigated via finite element method. Particularly the stress concentration factor has been calculated for various sizes of the corrosion pit and the results obtained have been discussed. [ABSTRACT FROM AUTHOR]

The paper presents a general procedure of numerical analysis of the steel structure in case of cyclic loading. The basic recommendations that can be applied to different details, are discussed. The article shows examples of the truss structure loaded with a crane track, but also applicable to other types of constructions. There are basic ideas of the whole process, which is divided into several parts. The beginning of the process is to determine the influence line from the simplified model of the whole structure. A stochastic estimation of the load effect associated with the load history in combination with the influence line is utilized. The complex 3D FEM model for estimation of residual life of the chosen detail is the main result of the analysis.

Chloride ions are nowadays the main cause of the degradation of steel and reinforce concrete construction in the vicinity of the road. On the other hand, chloride ions, usually in the form of de-icing salts or brine, are very important for safe winter traffic on the roads. This creates a slightly schizophrenic situation where it is necessary to ensure safe traffic in the winter period and at the same time to affect the service life of the structure as little as possible. The effect of the roadway on chloride deposition is a long-studied, but still imprecisely understood, part of the effect of chloride ions on structures in the vicinity of the roadway. This paper discusses the experimental measurement of chloride deposition in the vicinity of the I/11 road in the Czech Republic by dry plate method, wet candle method and corrosion coupons. Statistical analysis of correlation and regression is performed on the results of measurements by wet candle and horizontal dry plate methods. The methods are interdependent. A detailed analysis of the surface and chemical properties of the corrosion products is performed on the corrosion coupons. Using the corrosion loss, the environmental category C2 is determined. Observation of the microclimate in the vicinity of the roads gives to engineers a basis for the correct design of structures around the roads. The conclusions of the experimental measurements are intended to help engineers to design a structure that is safe, serviceable and sufficiently resistant to chloride ions within its service life [ABSTRACT FROM AUTHOR]

Various studies have been conducted to better understand the long-term corrosion mechanism for steels in a soil environment. Here, electrochemical acceleration methods present the most efficient way to simulate long-term corrosion. Among the various methods, galvanostatic testing allows for accelerating the surface corrosion reactions through controlling the impressed anodic current density. However, a large deviation from the equilibrium state can induce different corrosion mechanisms to those in actual service. Therefore, applying a suitable anodic current density is important for shortening the test times and maintaining the stable dissolution of steel. In this paper, to calibrate the anodic current density, galvanostatic tests were performed at four different levels of anodic current density and time to accelerate a one-year corrosion reaction of pipeline steel. To validate the appropriate anodic current density, analysis of the potential vs. time curves, thermodynamic analysis, and analysis of the specimen's cross-sections and products were conducted using a validation algorithm. The results indicated that 0.96 mA/cm2 was the optimal impressed anodic current density in terms of a suitable polarized potential, uniform corrosion, and a valid corrosion product among the evaluated conditions. [ABSTRACT FROM AUTHOR]

The main goal of this paper is to evaluate the burst pressure and structural integrity of a steel pipeline based on in-line inspection results, in respect to the grouping criteria of closely spaced volumetric surface features. In the study, special attention is paid to evaluation of data provided from the diagnostics using an axial excitation magnetic flux leakage technology in respect to multiple defects grouping. Standardized clustering rules were applied to the corrosion pits taken from an in-line inspection of the gas transmission pipeline. Basic rules of interaction of pipe wall metal losses are expressed in terms of longitudinal and circumferential spacing of the features in the colony. The effect of interactions of the detected anomalies on the tube residual strength evaluated according to the Det Norske Veritas Recommended practice was investigated in the current study. In the presented case, groups of closely-spaced defects behaved similarly as individual flaws with regard to their influence on burst pressure and pipeline failure probability. [ABSTRACT FROM AUTHOR]

Several corrosion mitigation methods are generally applied to pipelines exposed to corrosive environments. However, in the case of pre-buried pipelines, the only option for corrosion inhibition is cathodic protection (CP). To apply CP, the required current should be defined even though the pipeline is covered with various oxide layers. In this study, an electrochemical acceleration test was used to investigate the synthetic soil corrosion of a pre-buried pipeline. Potentiodynamic polarization experiments were first conducted to ascertain the corrosion current density in the environment, and galvanostatic measurements were performed to accelerate corrosion according to the operating time. In addition, corrosion current density and the properties of the rust layer were investigated via potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) tests. The variation in surface corrosion was subsequently analyzed via optical microscopy (OM) and X-ray diffraction (XRD) measurements. Finally, an empirical equation for the optimized CP current requirement, according to the pipeline service time, was derived. This equation can be applied to any corroded pipeline. [ABSTRACT FROM AUTHOR]