Anaerobic Corrosion of Reinforcement

2013 ◽  
Vol 569-570 ◽  
pp. 1124-1131 ◽  
Author(s):  
Ross O’Donovan ◽  
Brian D. O’Rourke ◽  
Kieran D. Ruane ◽  
John Justin Murphy
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Product ◽  
Steel Corrosion ◽  
Electrochemical Process ◽  
Steel Reinforcement ◽  
Detection Methods ◽  
Anaerobic Corrosion ◽  
The Subject ◽  
Corrosion Of Steel

Anaerobic corrosion of steel reinforcement is rarely reported and limited literature is available on the subject. Corrosion of steel is an electrochemical process requiring a supply of oxygen in the presence of moisture. Steel corrosion product usually occupies a much larger volume than the un-corroded steel resulting in cracked or spalled concrete. If the supply of oxygen is restricted, black rust may be formed by the process of anaerobic corrosion. Black rust is not expansive, which makes it particularly difficult to detect in reinforced concrete. This paper presents a case study of anaerobic corrosion in the Mizen Bridge, together with an in-depth review of anaerobic corrosion of reinforcement in concrete, outlining black rust formation, characteristics and detection methods.

scholarly journals Experimental Comparability Among Different Accelerated Reinforced Steel Concrete Corrosion Methods

2018 ◽  
Vol 7 (4.20) ◽  
pp. 209
Author(s):  
Mushtaq Sadiq Radhi ◽  
Maan S. Hassan ◽  
Iqbal N. Gorgis
Keyword(s):  
Reinforced Concrete ◽  
Steel Corrosion ◽  
Corrosion Current ◽  
Steel Reinforcement ◽  
Small Scale ◽  
Accelerated Corrosion ◽  
Galvanostatic Method ◽  
Reinforced Steel ◽  
Impressed Current ◽  
Corrosion Of Steel

The objective of this paper is to inspect the effect of changing the density of the impressed current and wetting-drying condition on accelerated corrosion of reinforced concrete specimens by a galvanostatic method.  Small-scale reinforced concrete columns were prepared and then artificially corroded by different setups of accelerated corrosion under an impressed current and also under different wetting-drying cycles for comparison. The density of the impressed current ranged between 50 and 500 µA/cm2 with different wetting-drying cycles periods. Corrosion current, and cracking were monitored throughout the accelerated corrosion period to determine the level of damage caused by the development of expansive reinforcement steel corrosion products, appearance of the first crack, and pattern of cracking.The results indicated that the galvanostatic method with wetting-drying sequences can be utilized effectively to simulate the normal corrosion of steel reinforcement in the concrete structure. The usage of different intensities of the current has no influence on the crack pattern. Though, increasing the current level leads to a substantial increase in the crack width due to corrosion of the steel reinforcement in a shorter time.  

scholarly journals Relationship model between surface strain of concrete and expansion force of reinforcement rust

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Fanxiu Chen ◽  
Zuquan Jin ◽  
Endong Wang ◽  
Lanqin Wang ◽  
Yudan Jiang ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Real Time ◽  
Steel Corrosion ◽  
Surface Strain ◽  
Concrete Cracking ◽  
Whole Process ◽  
Steel Bars ◽  
Relationship Model ◽  
Expansion Force ◽  
Corrosion Of Steel

AbstractConcrete cracking caused by corrosion of reinforcement could significantly shorten the durability of reinforced concrete structure. It remains critical to investigate the process and mechanism of the corrosion occurring to concrete reinforcement and establish the theoretical prediction model of concrete expansion force for the whole process of corrosion cracking of reinforcement. Under the premise of uniform corrosion of reinforcing steel bars, the elastic mechanics analysis method is adopted to analyze the entire process starting from the corrosion of steel bars to the cracking of concrete due to corrosion. A relationship model between the expansion force of corrosion of steel bars and the surface strain of concrete is established. On the cuboid reinforced concrete specimens with square cross-sections, accelerated corrosion tests are carried out to calibrate and verify the established model. The model can be able to estimate the real-time expansion force of reinforced concrete at any time of the whole process from the initiation of steel corrosion to the end of concrete cracking by measuring the surface strain of concrete. It could be useful for quantitative real-time monitoring of steel corrosion in concrete structures.

Test and Study on Impact of Corrosion on Bond Force between Steel and Concrete

2010 ◽  
Vol 36 ◽  
pp. 176-181
Author(s):  
Xian Feng He ◽  
Shou Gang Zhao ◽  
Yuan Bao Leng
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Rate ◽  
Concrete Structure ◽  
Steel Corrosion ◽  
Reinforced Concrete Structure ◽  
Bond Force ◽  
Steel Bars ◽  
Protection Layer ◽  
Corrosion Of Steel ◽  
The Impact

The corrosion of steel will have a bad impact on the safety of reinforced concrete structure. In severe cases, it may even be disastrous. In order to understand the impact of steel corrosion on the structure, tests are carried out to study corrosion and expansion rules of steel bars as well as the impact rules of corrosion on bond force between steel and concrete. The results show that wet and salty environment will result in steel corrosion; relatively minor corrosion will not cause expansion cracks of protection layers; when steel rust to a certain extent, it will cause cracks along the protection layer; when there exists minor corrosion in steel and the protection layer does not have expansion cracks, the bond force is still large and rapidly decreases as the corrosion rate increases.

scholarly journals Experimental Assessment of Rebar Corrosion in Concrete Slab Using Ground Penetrating Radar (GPR)

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Ahmad Zaki ◽  
Megat Azmi Megat Johari ◽  
Wan Muhd Aminuddin Wan Hussin ◽  
Yessi Jusman
Keyword(s):  
Ground Penetrating Radar ◽  
Structural Damage ◽  
Concrete Slab ◽  
Steel Corrosion ◽  
Steel Reinforcement ◽  
Reinforcement Corrosion ◽  
Dc Power ◽  
Reinforcement Bar ◽  
Ground Penetrating ◽  
Corrosion Of Steel

Corrosion of steel reinforcement is a major cause of structural damage that requires repair or replacement. Early detection of steel corrosion can limit the extent of necessary repairs or replacements and costs associated with the rehabilitation works. The ground penetrating radar (GPR) method has been found to be a useful method for evaluating reinforcement corrosion in existing concrete structures. In this paper, GPR was utilized to assess corrosion of steel reinforcement in a concrete slab. A technique for accelerating reinforcement bar corrosion using direct current (DC) power supply with 5% sodium chloride (NaCl) solution was used to induce corrosion to embedded reinforcement bars (rebars) in this concrete slab. A 2 GHz GPR was used to assess the corrosion of the rebars. The analysis of the results of the GPR data obtained shows that corrosion of the rebars could be effectively localized and assessed.

Mechanical Properties of Oxides Formed by Anaerobic Corrosion of Steel

2000 ◽  
Vol 663 ◽  
Author(s):  
N.R. Smart ◽  
A.E. Bond ◽  
J.A.A. Crossley ◽  
P.C. Lovegrove ◽  
L. Werme
Keyword(s):  
Mechanical Properties ◽  
Mild Steel ◽  
Corrosion Product ◽  
Photoelectron Spectroscopy ◽  
Spent Nuclear Fuel ◽  
Control Cell ◽  
Geologic Repository ◽  
Compressive Loads ◽  
Anaerobic Corrosion ◽  
Corrosion Of Steel

ABSTRACTIn Sweden, it is proposed that spent nuclear fuel should be encapsulated in sealed cylindrical canisters for disposal in a geologic repository. The canisters would consist of a thick ferrous inner container and a copper overpack. If mechanical failure of the copper overpack occurred, allowing water to enter, there would be a build up of ferrous corrosion product, which could induce stresses in the outer copper canister. This paper describes an apparatus, the ‘stress cell’, which was designed to measure the expansion caused by the anaerobic corrosion of steel under compressive loads. The apparatus consisted of a stack of steel and copper discs, which were immersed in simulated anoxic groundwater. A system of levers amplified the change in height of the stack, and the displacement was measured using sensitive transducers. Three cells were set up; two contained alternate mild steel and copper discs, and the third, a control cell, consisted of alternate stainless steel and copper discs. A slight contraction of the control cell was observed but no expansion was measured in the mild steel - copper cells.In parallel, coupons of mild steel and cast iron were corroded in anoxic, artificial groundwater at 50°C and 80°C for several months. The coupons were examined by atomic force microscopy (AFM) to determine the mechanical properties and the structure of the corrosion product films, and X-ray photoelectron spectroscopy (XPS) to identify the chemical composition of the film.

DEVELOPMENT OF EMBEDDED MINI-SENSOR FOR DIAGNOSIS OF CORROSION OF STEEL REINFORCEMENT IN CONCRETE NONDESTRUCTIVELY

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mohamed A. Ismail ◽  
Han-Seung Lee ◽  
Mohd Warid Hussin
Keyword(s):  
Reinforced Concrete ◽  
Polarization Resistance ◽  
Concrete Structures ◽  
Steel Reinforcement ◽  
Reinforced Concrete Structures ◽  
Chloride Ingress ◽  
Reinforcement Corrosion ◽  
Maintenance And Rehabilitation ◽  
Corrosion Of Steel ◽  
Non Destructive

Corrosion of steel reinforcement embedded in concrete is one of the main causes of degradation of reinforced concrete structures. Degradation occurs in reinforced concrete structures from corrosion caused by the Chloride ingress into concrete. That degradation has a severe impact on the structure in terms of maintenance and rehabilitation costs. Therefore, early detection of reinforcement corrosion is important for efficient maintenance, repair and planning. Meanwhile, the evaluation of the corrosion of reinforcement by non-destructive measurements have been used a lot. In particular CM-II (corrosion meter) is used to measure the polarization resistance, but has some disadvantages. Embedded mini-sensor has been developed in order to overcome these disadvantages. In this study, measurement of corrosion by using the mini-sensor is compared with the measured results by CM-II to verify the validity of the newly developed mini senor. Results show that there are agreement in trends of the parameters measured and as such the developed mini sensor has a promising start to be used.

Verification of the Efficiency of Anti-Corrosion Systems for Reinforced Concrete Constructions in a Laboratory Environment

2013 ◽  
Vol 357-360 ◽  
pp. 876-879
Author(s):  
Luboš Taranza ◽  
Rostislav Drochytka
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Corrosion Inhibitor ◽  
Corrosion Inhibitors ◽  
Steel Reinforcement ◽  
Testing Methods ◽  
Laboratory Environment ◽  
Corrosion Of Steel ◽  
High Information

Corrosion of steel constructions due to the affection of aggressive agents is one of the principal problems affecting reinforced concrete constructions. In critical cases, this phenomenon may cause static destabilisation of the construction and as a result, it is necessary to protect constructions using primary and secondary protection which significantly decreases this risk. This paper addresses the options for evaluating various types of protective anti-corrosion systems which use progressive corrosion inhibitor technology in a laboratory environment. Corrosion inhibitors efficiently slow down the course of corrosive processes on steel reinforcement and prolong the service life of building constructions. The rate of efficiency can be verified with high information capability in the laboratory by a series of testing methods.

scholarly journals THE PROPERTIES OF PITTING CORROSION OF STEEL REINFORCEMENT OF REINFORCED CONCRETE BEAMS

2017 ◽  
Vol 2 (3) ◽  
pp. 32-36
Author(s):  
Дронов ◽  
Andrey Dronov
Keyword(s):  
Reinforced Concrete ◽  
Pitting Corrosion ◽  
Concrete Beams ◽  
Concrete Structures ◽  
Steel Reinforcement ◽  
Reinforced Concrete Beams ◽  
Reinforced Concrete Structures ◽  
Damage Distribution ◽  
Chloride Environment ◽  
Corrosion Of Steel

Two types of steel reinforcement depassivation process: carbonation of concrete and chloride penetration are considered in the article. The comparison between the corrosion due to carbonation of concrete and the chloride-induced corrosion was carried out. It was found out, that chlorides induced corrosion is potentially more dangerous than that resulting from carbonation. Method of durable tests of reinforced concrete structures under the action of the gravitational load and the corrosive chloride environment is described in the article. The results of experimental research on reinforced concrete structures with corrosive damages to steel reinforcement are given in the article. The properties of corrosion cracking in the case of the pitting corrosion were determined. The character of corrosive damage distribution along the reinforcement bars and its effect on the strength of reinforced concrete beams were determined.

The Application of NUS Method for Concrete-Covered Steel Corrosion Monitoring

2015 ◽  
Vol 1124 ◽  
pp. 267-272
Author(s):  
Michal Matysík ◽  
Kristýna Timcakova
Keyword(s):  
Reinforced Concrete ◽  
Steel Corrosion ◽  
Structural Defects ◽  
Corrosion Monitoring ◽  
Ultrasonic Spectroscopy ◽  
Sensitive Material ◽  
Engineering Structures ◽  
Wide Range ◽  
Thick Steel ◽  
Corrosion Of Steel

The corrosion of steel elements in reinforced concrete can cause considerable damage to civil engineering structures. Early detection of corrosion is therefore very important. Steel in concrete is protected if the concrete pH is higher than 9.6. Carbonated concrete, unfortunately, has a lower pH and this causes that the unprotected steel reinforcement begins to corrode. Nonlinear ultrasonic spectroscopy (NUS) methods shows potential to be very reliable to identify the structure defects in a wide range of materials. These methods are based on the fact that crack-induced nonlinearity makes a sensitive material impairment indicator. This paper describes the ability of one of NUS methods for monitoring steel corrosion in reinforced concrete. It studies nonlinear interaction between elastic waves and structural defects caused by corrosion of steel in concrete. For research we used concrete beams with ten millimetres thick steel rods. These beams were exposed to accelerated degradation by chlorides. The paper presents the initial results of our research.

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