Numerical simulation and experimental investigation of the stray current corrosion of viaducts in the high-speed rail transit system

J. Electrochem. Sci. Eng.

Feng

et al. 2019

<p class="PaperAbstract">Corrosion of buried pipelines caused by stray currents is becoming a serious industrial and environmental problem. It is therefore necessary to study corrosion mechanisms of buried pipelines under DC stray currents in order to propose effective anti-corrosion measures. Since measurement of the potential is one of important ways to identify stray current intensity, the COMSOL Multiphysics software was used to simulate stray current corrosion dynamics of buried pipelines. It was also used to calculate the distribution and intensity changes of electrolyte potential in the cathodic protected system by solving Laplace’s three-dimensional equation. The obtained results showed that increased applied voltage leads to more positive shift of a pipeline potential, resulting in acceleration of stray current corrosion. On the contrary, increased soil resistivity can retard the corrosion process. The protected pipeline with a sacrificial anode suffers less corrosion interference than unprotected pipeline. Two crossed arrangement of pipelines makes no difference in corrosion of protected pipeline, but affects greatly on unprotected pipeline.</p>

Section: Resultssupporting

confidence: 83%

“…The boundary and initial conditions were set during the simulation, of the protected pipeline and anode ball constituting a whole [8]. The anode ball acts as an anode and produces the anodic oxidation reaction which defines the anode boundary condition.…”

Section: Governing Equationmentioning

confidence: 99%

Numerical modelling of buried pipelines under DC stray current corrosion

J. Electrochem. Sci. Eng.

Feng

et al. 2019

“…Stray AC current would not be a major concern for corrosion of rail itself (Hernandez et al 2009), instead, research on stray AC current corrosion has been focused on other surrounding metallic structures, e.g. buried pipelines (Hosokawa et al 2004) and viaducts (Hong et al 2017). As to stray DC current, generally applied for subway and urban railway system, much of the research has also been focused on the corrosion of other surrounding metallic structure (Kale et al 1999;Xu and Li 2015), but it has been found to accelerate corrosion of rail base in the presence of humidity and deposited salt, while corrosion was less important in the absence of DC current (Hernandez et al 2009).…”

Section: Other Forms Of Corrosion 331 Stray Current Corrosionmentioning

confidence: 99%

Corrosion of rail tracks and their protection

Deng

et al. 2020

Corrosion Reviews

Rapid development of railway industry makes safety increasingly important. Wear, contact-impact, fatigue and corrosion are important factors initiating rail track degradation from the beginning, while corrosion attracts far less attention than other issues. Direct corrosion cost due to railway corrosion in China was 18.88 billion RMB, so corrosion definitely deserves more attention. This work has reviewed studies focussing exclusively on rail corrosion, including corrosion forms, protection and detection technologies. General corrosion on large rail surface is not limiting, while crevice corrosion between rail and liner, resulting in thinning of rail foot, is regarded significant but overlooked. Moreover, reciprocating micro-motion between rail foot and liner mechanically assists the ongoing of crevice corrosion. However, it was mentioned in very few reports and not investigated extensively. Coating and surface modification may be applied for mitigation of rail track corrosion. The weakness of coating is poor mechanical properties, while surface modification, including thermal spraying and laser cladding, may be a better way. Development of novel steel is another effective method, but loss of mechanical properties becomes obstacles for practical applications. Ultrasonic and infrared have been applied for detection, while more advanced technologies are promising. Suggestions are made on specific research topics in this field.

“…Current test methods for studying atmospheric galvanic corrosion include exposure testing and laboratory testing. These methods have been used for many decades however they are limited in their abilities to test materials in complex geometries for a variety of environments and in a short period of time …”

Section: Introductionmentioning

confidence: 99%

“…Numerical simulation of the atmospheric corrosion damage can accurately evaluate the corrosion status, then to provide the corrosion conditions for the investigation of corrosion fatigue, and finally establish the baseline for the service life prediction of aircraft. The atmospheric corrosion coupled with the fatigue effect caused by the vibration leads to the fracture of aircraft structure.…”

Section: Introductionmentioning

confidence: 99%

A method of atmospheric corrosion prediction for aircraft structure

Chen

Huang

et al. 2018

Materials & Corrosion

A simulation prediction system, test pieces → flat test pieces → structural parts, for the atmospheric corrosion of aircraft is proposed to provide guidance for aircraft anti‐corrosion material selection and outfield maintenance. Based on the shell current distribution, a COMSOL corrosion simulation prediction model was constructed and applied to three types of test parts. The correctness of simulation principle is verified by comparing the galvanic current of simulation and test on each electrode surface of multi‐electrode system. Comparing the simulated potential distribution at 100 µm electrolyte layer with the corrosion morphology after 12 wet–dry corrosion periods, it is found that simulation and test are in good agreement. It is also proved that the 100 µm static liquid film can reflect the corrosion of this kind of wet–dry cycle. Comparing the corrosion depths of different periods at three different points and the simulated corrosion depth with time, it is found that the corrosion depth of the first four periods was larger than the simulated depth, which was less than the simulated value after four periods. The model was applied to the local structural parts of aircraft. Then, corrosion position and corrosion area were predicted. The results were compared with the accelerated test results to verify the accuracy of the model's prediction of structural parts. At the same time, the corrosion depth of the structural parts was also predicted.