Assessment of Corrosion of Steel in Concrete Structures by Magnetic Based NDE Techniques

2009 ◽  
pp. 119-119-13 ◽  
Author(s):  
A Ghorbanpoor ◽  
S Shi
Keyword(s):  
Concrete Structures ◽  
Corrosion Of Steel

Durability of port reinforced concrete structures (Far East and Sakhalin)

2021 ◽  
Author(s):  
Sergey Leonovich ◽  
Evgeniy Shalyy ◽  
Elena Polonina ◽  
Elena Sadovskaya ◽  
Lev Kim ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Probabilistic Models ◽  
Far East ◽  
Concrete Structures ◽  
Life Cycles ◽  
Reinforced Concrete Structures ◽  
Joint Work ◽  
Port Structures ◽  
Corrosion Of Steel

Section I of the monograph is devoted to an urgent problem - forecasting the durability of port reinforced concrete structures, the destruction of which is associated with corrosion of steel reinforcement caused by chloride aggression and carbonation of concrete. The analysis of models for calculating the service life of structures and experimental data is carried out, the life cycles for the main degradation processes in concrete and reinforcement, the periods of initiation and propagation of corrosion are considered, the influence of environmental factors (temperature, humidity) and the quality of concrete (In/C, cement consumption, diffusion coefficient) on the kinetics of chloride penetration and the movement of the carbonation front is taken into account. Probabilistic models of basic variables are considered, the limiting states of port reinforced concrete structures for the durability of reinforced concrete structures based on the reliability coefficient for service life are formulated. Sections II and III describe modern methods of restoration and restoration of reinforced concrete port structures subjected to corrosion destruction using nanofibrobeton. The concept of multilevel reinforcement has been implemented. Methods of experimental fracture mechanics were used to evaluate the joint work of exploited concrete and reinforcement nanofibre concrete. It is intended for scientific and engineering staff of universities, research and design organizations.

scholarly journals Corrosion Prevention on Coated Rebars and Fiber in R.C Slabs

2018 ◽  
Vol 7 (3.34) ◽  
pp. 36
Author(s):  
Dr M.Tamil Selvi ◽  
Ms. J Hathari Evangalin ◽  
M.s S. Gayathri
Keyword(s):  
Research Work ◽  
Concrete Structures ◽  
Steel Reinforcement ◽  
Accelerated Corrosion ◽  
Structural Problems ◽  
Nylon Fiber ◽  
Cell Measurement ◽  
Accelerated Corrosion Test ◽  
Rc Slabs ◽  
Corrosion Of Steel

Concrete structures prevail primarily due to prior attrition of steel due to preterm failure of rebars. The major cause of deterioration is the corrosion of the steel reinforcement, that can lead to structural problems. By utilizing our knowledge on corrosion of steel reinforcement, concrete structures could be made more durable. The research work is intend at arrestcorrosion in RC slabs by glazing silicon tombac to the steel rods. Nylon fiber is induced in concrete to attain strength for the concrete. A study report carried the effects of coating material between the conventional and fibers in concrete was compared with that of uncoated material between the conventional and fiber in concrete rebar’s. A continuous corrosion process is accelerated by inducing direct current to rebars. Process used to prompt corrosion is Accelerated corrosion test and Half-cell measurement.  

scholarly journals Evaluation of the Bond-to-Concrete Properties of GFRP Rebars in Marine Environments

2018 ◽  
Vol 3 (4) ◽  
pp. 44 ◽  
Author(s):  
Alvaro Ruiz Emparanza ◽  
Francisco De Caso Y Basalo ◽  
Raphael Kampmann ◽  
Itziar Adarraga Usabiaga
Keyword(s):  
Bond Strength ◽  
Concrete Structures ◽  
Steel Reinforcement ◽  
Fiber Reinforced Polymer ◽  
Multiple Time ◽  
Bond Performance ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Different Temperatures ◽  
Corrosion Of Steel

Increased traffic in combination with growing environmental impacts have led to the accelerated degradation of built infrastructure. In reinforced concrete structures, the corrosion of steel reinforcement is the predominant cause of deterioration. Thus, over the last years the use of glass fiber reinforced polymer (GFRP) composites as internal reinforcement bars (rebars) for concrete structures has been evaluated, and has been proved to be a viable alternative to traditional steel reinforcement mainly due to its tensile strength and non-corrosive nature. However, thus far, the GFRP rebar market is diverse and manufacturers around the world produce GFRP rebar types with different surface enhancements to improve the bond to concrete characteristics. In this study, the bond performance of three dissimilar GFRP rebar types (sand coated, helically grooved and with surface lugs) was evaluated over time in seawater environments, with a focus on the bond strength. Accordingly, specimens were exposed to seawater in circulating chambers at three different temperatures (23 °C, 40 °C and 60 °C) for multiple time periods (60 and 120 days). To evaluate the bond performance, pullout tests were conducted according to ASTM D7913. The results showed that the bond strength varied with the surface enhancement features. However, the bond strength did not vary significantly with exposure time and temperature for all three evaluated rebar types.

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.

Prediction of durability of structural concrete in aggressive exposures

2018 ◽  
Author(s):  
Сергей Леонович ◽  
Sergey Leonovich ◽  
Валентин Доркин ◽  
Valentin Dorkin ◽  
Оксана Чернякевич ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Building Materials ◽  
Limit State ◽  
Concrete Structures ◽  
Life Cycles ◽  
Reinforced Concrete Structures ◽  
Concrete Durability ◽  
Concrete Carbonation ◽  
Corrosion Of Steel

The monograph is devoted to the prediction of the longevity of reinforced concrete structures, the destruction of which is associated with corrosion of steel reinforcement caused by chloride aggression or concrete carbonation. On the basis of a comprehensive analysis of models for calculating the service life of structures and experimental data, preference is given to the mathematical model Dura Crete. Life cycles for the main degradation processes in concrete and reinforcement, periods of initiation and propagation of corrosion are considered. Particular attention is paid to the influence of environmental factors and the quality of concrete on the kinetics of chloride penetration and movement of the carbonization front. Formulated limit state design reinforced concrete durability in chloride attacks and carbonation. The basic provisions of the method of calculating the durability of reinforced concrete structures, based on the use of the reliability coefficient for the service life. The practical assessment of service life of reinforced concrete elements taking into account stochastic processes in concrete and reinforcement is made. Verification of the model reliability is performed. For all those interested in the issues of building materials and processes occurring in them.

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.

Determination of the Influence of Carbonation of Concrete and Corrosion of Steel on Reinforced Concrete Condition

2015 ◽  
Vol 1124 ◽  
pp. 225-230 ◽  
Author(s):  
Kristýna Timcakova ◽  
Daniela Štefková ◽  
Zdeněk Chobola
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Poor Quality ◽  
Protective Properties ◽  
Impact Echo ◽  
Concrete Condition ◽  
Almost All ◽  
Corrosion Of Steel ◽  
Impact Echo Method

Almost all reinforced concrete structures which are exposed to weather effects are threatened by corrosion. The corrosion of steel elements in structures has an influence on lifetime these constructions and adversely affects their properties. However, the steel in concrete structures is protected against corrosion due to the properties of concrete such as high pH or impermeability, but if the concrete is of poor quality and his protective properties are insufficient the corrosion can occur. A problem causes the action of carbon dioxide which has the effect of lowering the pH below the critical value and thereby accelerating the corrosion.Non-destructive methods such as Impact-echo method offer the possibility of easy and quickly detection of initial damage of structure and thus can prevent the occurrence of permanent damage to the whole construction.This article describes the development of corrosion which is caused by carbonation of the concrete and supported by action of chlorides by using Impact-echo method. The paper presents results obtained on the reinforced concrete samples with one steel rod passing through the center. After carbonation concrete the samples were exposed accelerated controlled degradation in aqueous NaCl solution for 4 months.

Corrosion Assessment and Control Techniques for Reinforced Concrete Structures

2020 ◽  
pp. 226-259
Author(s):  
Md Daniyal ◽  
Sabih Akhtar
Keyword(s):  
Reinforced Concrete ◽  
Electrochemical Techniques ◽  
Substantial Reduction ◽  
Concrete Structures ◽  
Steel Corrosion ◽  
Reinforced Concrete Structures ◽  
Steel Reinforced Concrete ◽  
Inspection Systems ◽  
Critical Requirement ◽  
Corrosion Of Steel

The steel reinforced concrete structures perform well in various environmental conditions, but structures may undergo premature damage in aggressive environments such as marine or acidic, primarily due to steel corrosion, and substantial reduction in service life occurs. This also causes huge economical loss and create safety and environmental problems. The repair and maintenance of steel reinforced concrete structures for their safety needs effective monitoring and inspection systems for evaluating the corrosion condition of steel. Since the corrosion of steel reinforcement occurs through electrochemical reactions, electrochemical methods are suitable to study the corrosion processes. In this chapter, some commonly used electrochemical techniques have been comprehensively explained. In addition, there is a critical requirement to develop effective and long-lasting techniques to control the corrosion of steel. Hence, some of the commonly used corrosion control methods have been comprehensively described in this chapter.

The Influence of Micro Algae on Corrosion of Steel in Fly Ash Geopolymer Concrete: A Preliminary Study

2012 ◽  
Vol 626 ◽  
pp. 861-866 ◽  
Author(s):  
Monita Olivia ◽  
Navid Moheimani ◽  
Reza Javaherdashti ◽  
Hamid R. Nikraz ◽  
Michael A. Borowitzka
Keyword(s):  
Fly Ash ◽  
Corrosion Potential ◽  
Concrete Structures ◽  
Algal Growth ◽  
Microbiologically Influenced Corrosion ◽  
Metallic Surface ◽  
Geopolymer Concrete ◽  
Preliminary Study ◽  
Corrosion Of Steel ◽  
The Impact

Chloride is not the only main cause of corrosion of reinforced concrete structures in seawater environment. Microorganisms, such as bacteria and microalgae, in the seawater can induce microbiologically influenced corrosion (MIC) that leads to degradation of the concrete structures by formation of biofilm on the metallic surface. In this preliminary study, the impact of microalgae on the corrosion of steel reinforced bars in fly ash geopolymer concrete was studied. Corrosion potential, algae cells number, and pH measurement were carried out for fly ash geopolymer concrete and a control mix (Ordinary Portland Cement) samples. The results indicate that the corrosion potential of fly ash geopolymer concrete was influenced by the cathodic reaction during photosynthesis activities. The geopolymer concrete in algae-inoculated medium was found to be more tolerant to algal growth than the control mix (OPC concrete). There was a positive correlation between algae cell densities and the potential reading of the geopolymer.

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