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In the present study, an effort has been made to estimate the effect of significant parameters on the vulnerability of steel reinforcement to corrosion, using both impressed current density technique and Tafel extrapolation method.

Five sets of tests were performed. Corrosion vulnerability of various diameters, temperature and pH effect on the corrosion process, potential corrosion tendency after a precorrosion period and declination from the theoretical damage prediction model are some of the parameters examined

The results of the tests provide useful information on the main parameters, determining the quality of the corrosion damage.

The originality of the present study is the fact that an effort has been made to estimate the effect of significant parameters on the vulnerability of steel reinforcement to corrosion, using both impressed current density technique and Tafel extrapolation method. Interesting conclusions emerged.

The safety of reinforced concrete structures is generally related to the expected service life of their individual materials. Corrosion damage manifesting on steel reinforcement is usually underestimated, although it greatly affects both load bearing capacity and plastic deformation limits of steel reinforcement. Corrosion damage degree has a great impact on the life expectancy of structures. This paper aims to discuss these issues.

In the present study, an effort has been made to examine and present critical parameters, which are significantly responsible for the differentiation of the corrosion damage level, as far as mass loss is concerned. Consequently, the size effect of the exposed – to the aggressive conditions – area of the specimen, as well as the volume of the protected (against corrosion) area, was examined in detail.

Differential aeration greatly affects the results of corrosion on the material, given that under both high and low oxygen concentration corrosion process is still ongoing.

Findings proceeded are worth mentioning, as they may contribute to a more pertinent evaluation of the corrosion damage (as far as mass loss is concerned), restricting the risk of erroneous predictions concerning the mechanical behavior of steel reinforcement.

This paper aims to present a lightened 3D finite element model (FEM) for coupled electromagnetic thermal simulation of the induction thermography non-destructive testing (NDT) technique to reduce the computation time.

The time harmonic electromagnetic problem is expressed in A – ϕ formulation and lightened by using the surface impedance boundary condition (SIBC) applied to both the massive induction coil surface and the surface of conductor workpiece including open cracks. The external circuit is taken into account by using the impressed voltage or the impressed current formulation. The thermal diffusion in the workpiece is solved by using surface electromagnetic power density as thermal source.

The accuracy and the usefulness of the method for the design of the induction thermography NDT technique have been shown with acceptable deviation compared with a full FEM model. It is also observed that at high frequency, when the ratio between the local radius of the conductor and the skin depth is high, a very good accuracy can be obtained with the SIBC methods. At lower frequency, the effect of the curvature of the surface becomes significant. In this case, the use of the Mitzner’s impedance can help to correct the error.

The SIBC can be used for both massive coil and workpieces with open cracks to alleviate 3D FEMs of the coupled electrothermal model. The implementation in matrix form of the coupled electrothermal formulation is given in details. The comparisons with reference analytical solution and full 3D FEM show the accuracy and performance of the method. In the test case presented, the computation time is 6.6 times lower than the classical model.

We applied minimum norm estimations using different regularization techniques to the solution of the biomagnetic inverse field problem. Using magnetic field data measured with a multi‐channel‐SQUID‐sensor‐system we computed reconstruction of the impressed current density distributions which were generated by extended current sources placed inside a human torso phantom. The common inverse techniques usually applied in modern biomedical investigations in bioelectricity or biomagnetism are compared, and their aptitude for reconstruction of 3D current sources in space was evaluated. We analyzed the impact of using magnetic data, electrical data, and combination of both respectively on the localization of an equivalent current dipole (ECD). Finally, we use a visualization tool which enables a comparison of current density reconstruction. The study is, in parts, related to the new TEAM problem No. 31.

This paper aims to develop an electrochemical dechlorination method for large objects in a short time, which were for a long time in the sea. Traditionally, in conservation, chlorides are extracted from marine iron artifacts using complete immersion of those objects in alkaline solutions with or without electrolysis. However, these techniques are time-consuming and very costly, especially when applied to large marine artifacts such as cannons and anchors.

An appropriate sponge was chosen based on resistance to NaOH and the rate of exacted chlorides. Application of electrochemical dechlorination in situ and removal of chloride were measured by the scanning electron microscope (SEM)-EDAX method on the corrosion products and by titration of the electrolysis solution. X-ray diffraction (XRD) method is used for identification of corrosion products before and after application of electrochemical chloride extraction.

The electrochemical chloride extraction (ECE) method is applied against the corrosion of reinforced concrete. From the authors’ research, it is obvious that ECE can successfully extract chlorides from dried large metallic objects exported from the sea. The method of ECE removes the majority of chlorides from the metal during conservation treatment so that the application of organic coating will allow the object to remain stable over a long period.

A new methodology was developed for dechlorination of metallic objects exported from the sea in a short time and thus the consumption of chemical reagents was cut down.

Following the early cathodic protection work with zinc, and later magnesium, sacrificial anodes, there has been an increasing interest in the use of impressed current techniques. In the following article the author describes the method of operation of a corrosion product impressed current anode and, in particular, the formation of a conducting oxide film on a lead alloy. Some particular designs of these anodes for practical use in cathodic protection systems and their estimated performance are reviewed.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

IMPRESSED CATHODIC CURRENT for ships' hull protection by two techniques has been proposed, firstly by trailing a wire either from outriggers amidships or over the stern and spreading current from this trailed anode to the ship, or secondly, and now almost exclusively, by attaching anodes in some streamlined form to the hull of the vessel. The problems with the trailing wire anode have been very well aired and described and the mathematics of the system were very clearly stated by the originators of this modern technique, Vosnick and Vissher.1 The problems with hull‐mounted impressed current anodes, however, have to a large extent been glossed over and very little analysis has been made of the size and shape of the anode and more particularly of the size, shape, and quality of the insulation around the anode on the hull.

The basic aspects and mechanism of corrosion of steel piles in sea water are briefly discussed. The effects of parameters viz. pH, salinity, dissolved oxygen, temperature and wind velocity responsible for the corrosion of steel piles have been presented. The methods used for corrosion control and the impressed current cathodic protection technique in particular, with its merits, when applied to under‐water marine structures are outlined. The values and importance of potential required at the surface under protection, surface current density requirement and its distribution for the protection of steel structures under different service conditions useful for the design of cathodic protection systems are presented. The characteristics of various types of anode materials with a special reference to the latest platinized (Platinum‐Niobium) niobium anodes, with their merits, over other types of anodes are tabulated. The basic considerations required for the design of cathodic protection and the design of the system have been presented.

This work aimed to study the effect of environment resistivity and distance between cathode and anode on the required cathodic protection current density of buried carbon steel pipes and determine the impressed current that gives full protection to bare and coated pipes by two different coatings.

The experimental apparatus is an electrochemical cell composed of carbon steel pipe of 10 cm in length as a working electrode in addition to reference and auxiliary electrodes and direct current power supply. The cathodic protection tests were carried out in five solutions of different concentrations of sodium chloride and distilled water with different resistivities.

It was found that the cathodic protection current density increased with a decrease in environment resistivity and increase in the distance between cathode and anode. Additionally, the cathodic protection current density of coated pipes by two different polymers increased with a decrease in the environment resistivity and increasing number of coating defects.

icp = D/A + B?2, where: icp = cathodic protection current density; D = distance between anode and cathode; ? = environment resistivity; A = constant (0.2104); and B = constant (0.864 × 10−6).