scholarly journals Azadirachta indica Leaf Extract as Green Corrosion Inhibitor for Reinforced Concrete Structures: Corrosion Effectiveness against Commercial Corrosion Inhibitors and Concrete Integrity

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3326
Author(s):  
Benjamin Valdez-Salas ◽  
Ramiro Vazquez-Delgado ◽  
Jorge Salvador-Carlos ◽  
Ernesto Beltran-Partida ◽  
Ricardo Salinas-Martinez ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Carbon Steel ◽  
Corrosion Inhibitor ◽  
Construction Industry ◽  
Azadirachta Indica ◽  
Leaf Extract ◽  
Concrete Structures ◽  
Chloride Ions ◽  
Reinforced Concrete Structures ◽  
Cell Potential

The construction industry has extensively demanded novel green inhibition strategies for the conservation and protection of carbon steel-reinforced concrete structures. For the first time, the effect of Azadirachta indica leaf extract (Neem) as a potential corrosion inhibitor of carbon steel in reinforced concrete under corrosion in saline simulated media was evaluated. To assess the corrosion inhibition behavior of the Neem natural organic extract, three inorganic commercial inhibitors were tested to compare following the criteria established by Stratful for half-cell potential under a simulated chloride environment. Moreover, the effect of concrete integrity by the Neem treatment was recorded after different temperature conditions, slump, weight alteration, air content, compressive strength, and chloride-ions penetration. The results suggested that the Neem treatments did not alter the concrete integrity and the physicochemical parameters. We reached a promoted long-term corrosion protection of 95% after 182 days of evaluation. Thus far, our current results open up a new promising “green” road to the conservation of carbon steel in reinforced concrete for the construction industry.

scholarly journals The electrochemical performance and modification mechanism of the corrosion inhibitor on concrete

2021 ◽  
Vol 28 (1) ◽  
pp. 352-562
Author(s):  
Meiyan Hang ◽  
Minghui Jiang ◽  
Junwei Xu ◽  
Teng Cheng ◽  
Hao Wang ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Electrochemical Performance ◽  
Corrosion Inhibitor ◽  
Electrode Potential ◽  
Concrete Structures ◽  
Corrosion Damage ◽  
Chloride Ions ◽  
Reinforced Concrete Structures ◽  
Chloride Corrosion ◽  
Chloride Environment

Abstract The purpose of this study was to solve the chloride corrosion damage problems of the rebar in reinforced concrete structures under the chloride environment. The effects of 1.0% triethanolamine (abbreviated as 1.0% TEA), 1.0% Ca(NO2)2, and 0.5% TEA + 0.5% Ca(NO2)2 (abbreviated as 1.0% composite corrosion inhibitor) on the electrochemical performance and modification mechanism of the mortar specimens were investigated by combining macro experiment and microanalysis. The results showed that the electrode potential of the rebar was effectively improved by incorporating the 1.0% composite corrosion inhibitor. This composite corrosion inhibitor displayed the ability to stabilize the electrode potential of the rebar; it also formed a passive film on the surfaces of the rebar, protected the rebar from chloride attack, and achieved satisfactory electrochemical performance. In addition, it could also effectively improve the strength of the mortar specimens and possessed the strong ability to bind chloride ions, thus signifying that it could promote cement hydration and accelerate the formation of cement to form AFt crystals. Therefore, the results of this investigation confirmed that this composite corrosion inhibitor could be effectively used in practical engineering to prevent the corrosion of reinforced concrete structures.

Areca Catechu: An Eco-Friendly Corrosion Inhibitor for Reinforced Concrete Structures in Corrosive Mediums

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Seyedmojtaba Ghoreishiamiri ◽  
Pandian Bothi Raja ◽  
Mohammad Ismail ◽  
Seyedeh Faezeh Hashemi Karouei ◽  
Parham Forouzani
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Inhibitor ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
Areca Catechu

Passive corrosion control and active corrosion prevention of the reinforced concrete structures by electrochemical chloride removal and inhibitors

2013 ◽  
Vol 61 (1) ◽  
pp. 32-37 ◽  
Author(s):  
Guofu Qiao ◽  
Yi Hong ◽  
Tiejun Liu ◽  
Jinping Ou
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Concrete Cover ◽  
Reinforced Concrete Structures ◽  
Reinforcing Steel ◽  
Corrosion Control ◽  
Cell Potential ◽  
Content Type ◽  
Chloride Removal ◽  
Active Corrosion

Purpose – The aim of this paper was to investigate the passive corrosion control and active corrosion protective effect of the reinforced concrete structures by electrochemical chloride removal (ECR) method and inhibitors approach, respectively. Design/methodology/approach – The concentration of aggressive chloride ion distributed from the reinforcing steel to the surface of the concrete cover was analyzed during the ECR processes. Besides, the half-cell potential, the concrete resistance R c , the polarization resistance R p and the capacitance of double layer C dl of the steel/concrete system were used to characterize the electrochemical performance of the concrete prisms. Findings – The effectiveness of ECR could be enhanced by increasing the amplitude of potential or prolonging the time. Inhibitor SBT-ZX(I) could successfully prevent the corrosion development of the reinforcing steel in concrete. Originality/value – The research provides the scientific basis for the practical application of ECR and inhibitors in the field.

scholarly journals AERVA LANATA LEAF EXTRACT AS A CORROSION INHIBITOR FOR CARBON STEEL IN CHLORIDE ENVIRONMENT

2018 ◽  
Vol 6 (11) ◽  
pp. 153-162
Author(s):  
Rajesh V. ◽  
E. U. B. Reddi ◽  
T. Byragi Reddy ◽  
Ch. Durga Prasad ◽  
B. Prasanna Kumar
Keyword(s):  
Carbon Steel ◽  
Corrosion Inhibitor ◽  
Leaf Extract ◽  
Inhibition Efficiency ◽  
Aggressive Medium ◽  
Chloride Ions ◽  
Aqueous Environment ◽  
Aerva Lanata ◽  
Ph Range ◽  
Chloride Environment

The present study was initiated with an objective of investigating a plant extract as an effective corrosion inhibitor useful for protection of carbon steel in aqueous environment containing chloride ions. For this purpose, the leaf extract of the plant ‘Aerva lanata’ belonging to Amaranthaceae family of genus Aerva was chosen. The required optimum concentration of the extract for an effective inhibition was found to be 5 %, resulting in the inhibition efficiency of 95 % against corrosion of carbon steel in 200 ppm of NaCl solution. The extract introduced as a corrosion inhibitor was found to be effective in the pH range from 4.0 to 9.0. The extract could retain its inhibition efficiency for about an immersion period of 60 days and also up to a temperature of 333 K. The 5 % extract was found to control corrosion of carbon steel in highly aggressive medium containing 300 ppm of NaCl also. In order to maintain the protective nature, the required concentration of the extract was 2 %. From these studies, it was inferred that the Aerva lanata leaf extract exhibits good inhibitive properties for carbon steel in aqueous environment in wide ranges of pH, temperature and aggressiveness of medium.

scholarly journals Experimental study of the influence of crack width due to corrosion behaviour using different measurement methods and different exposures

2019 ◽  
Vol 289 ◽  
pp. 08005
Author(s):  
Martin Schneider ◽  
Georg Gardener
Keyword(s):  
Reinforced Concrete ◽  
Crack Width ◽  
Corrosion Behaviour ◽  
Concrete Strength ◽  
Concrete Structures ◽  
Chloride Ions ◽  
Reinforced Concrete Structures ◽  
Reinforcing Steel ◽  
Surface Corrosion ◽  
Potential Mapping

Corrosion of reinforcing steel has a great influence in reducing the lifetime of concrete structures; Carbonation of the concrete pore solution causes surface corrosion on the steel and diffusion of chloride ions through the capillary system of the concrete cover causes pitting corrosion on the steel surface. Corrosion of metals is highly dependent on the environmental conditions. Exposure to chloride ions can be critical to the service life of reinforced concrete structures. The durability of reinforced concrete structures exposed to deicing salt or marine environments can be affected by impact of chloride ions. Detection methods for the rate of corrosion of non-destructive and destructive procedures were analysed. The potential mapping applied on the concrete surface was discussed as a standard method for corrosion detection and will be explained in detail including the application boundaries of the method. It is assumed that the corrosion behaviour of reinforcing steel depends on crack widths. To analyse that, 8 coated and 8 uncoated test samples with different concrete strength classes were used. The concrete objects were exposed to a 3% sodium chloride solution. The corrosion behaviour of reinforcing steel is analysed by using potential mapping with different reference electrodes (Ag/AgCl and Cu/CuSO4). The results show a significant correlation between crack size and protection system on the surface. The maximum crack width with a low indication of corrosion was found to be 0.1 mm.

scholarly journals Experimental and Empirical Time to Corrosion of Reinforced Concrete Structures under Different Curing Conditions

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Ahmed A. Abouhussien ◽  
Assem A. A. Hassan
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Test ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Curing Conditions ◽  
Expected Time ◽  
Corrosion Initiation ◽  
Accelerated Corrosion Test

Reinforced concrete structures, especially those in marine environments, are commonly subjected to high concentrations of chlorides, which eventually leads to corrosion of the embedded reinforcing steel. The total time to corrosion of such structures may be divided into three stages: corrosion initiation, cracking, and damage periods. This paper evaluates, both empirically and experimentally, the expected time to corrosion of reinforced concrete structures. The tested reinforced concrete samples were subjected to ten alternative curing techniques, including hot, cold, and normal temperatures, prior to testing. The corrosion initiation, cracking, and damage periods in this investigation were experimentally monitored by an accelerated corrosion test performed on reinforced concrete samples. Alternatively, the corrosion initiation time for counterpart samples was empirically predicted using Fick’s second law of diffusion for comparison. The results showed that the corrosion initiation periods obtained experimentally were comparable to those obtained empirically. The corrosion initiation was found to occur at the first jump of the current measurement in the accelerated corrosion test which matched the half-cell potential reading of around −350 mV.

The Crack Control of Reinforced Concrete Structures

2014 ◽  
Vol 1079-1080 ◽  
pp. 300-303
Author(s):  
Gang Wang
Keyword(s):  
Reinforced Concrete ◽  
Construction Industry ◽  
Fundamental Problem ◽  
Concrete Structures ◽  
Good Effect ◽  
Reinforced Concrete Structures ◽  
Global Integration ◽  
Crack Control ◽  
Construction Companies ◽  
The Future

With the continuous development of the level of China's political, economic and social, the construction industry also obtained great progress. At the same time, the quality problems of all kinds of building has become a very serious problem which restricting the expansion of the scale of the enterprise. Along with the global integration, exchanges between domestic and foreign construction companies are becoming more and more frequent. The quality issues is in relation to the future of the construction industry. Only to deal with this problem, we can win in the international competition of the company. In the future for a long period of time, the construction industry will have a greater impact on the national economy of our country. If we can not solve the fundamental problem restricting the development of construction industry, the development of this industry will not sustainable. There is a very serious problem In the course of engineering construction which is the crack control of reinforced concrete structures. If this problem can be solved, we can produce a relatively good effect in the development of China's construction industry.

Ultrasonic C-Scan Imaging: Preliminary Evaluation for Corrosion and Void Detection in Posttensioned Tendons

2003 ◽  
Vol 1827 (1) ◽  
pp. 44-52 ◽  
Author(s):  
Shivprakash Iyer ◽  
Andrea J. Schokker ◽  
Sunil K. Sinha
Keyword(s):  
Reinforced Concrete ◽  
Concrete Structures ◽  
Corrosion Monitoring ◽  
Reinforced Concrete Structures ◽  
Preliminary Evaluation ◽  
Cell Potential ◽  
Impact Echo ◽  
Bridge Structures ◽  
Processing Techniques ◽  
User Friendly

Corrosion of the nation’s transportation infrastructure is a widespread and costly problem. The most prevalent durability issue in reinforced concrete structures is chloride-induced corrosion of the reinforcing steel. A reliable method of determining grout voids and corrosion levels in posttensioned bridge structures is needed. Traditional techniques of corrosion monitoring (e.g., half-cell potential and corrosion rate measurement) are problematic when used in this type of structure, as are standard nondestructive evaluation (NDE) methods, such as impact echo. C-scan imaging, an ultrasonic technique used primarily in the composites industry for detecting delamination, is examined as a method of evaluating grouted posttensioned tendons. This method exhibits many promising qualities: it can be used for internal or external tendons and on metal or plastic ducts; access to only one side of a specimen is required; strong imaging allows easy interpretation of results; the technique poses no risk to users or the environment; and the method has strong potential for development as a handheld field tool. The C-scan technique may be valuable for the investigation of not only posttensioning applications but other types of reinforced concrete structures as well. Results of preliminary investigations on lab specimens indicate that the C-scan technique holds promise. The ultimate goal of the research is to provide a user-friendly, robust system for the NDE of posttensioned tendons for voids, corrosion, and wire breaks. Recommendations for optimal acquisition and processing techniques as well as for the future development of the equipment as a field tool are proposed.

scholarly journals CONCEPTUAL SCHEME OF ENVIRONMENTAL SAFETY OF URBAN AREAS ADJACENT TO THE FACILITIES OF THE CONSTRUCTION INDUSTRY

2020 ◽  
Vol 4 (157) ◽  
pp. 103-108
Author(s):  
S. Krivileva ◽  
V. Vlasenko
Keyword(s):  
Reinforced Concrete ◽  
Construction Industry ◽  
Urban Areas ◽  
Biological Diversity ◽  
Concrete Structures ◽  
Environmental Safety ◽  
Reinforced Concrete Structures ◽  
Conceptual Scheme ◽  
Residential Areas ◽  
Main Components

The existing approaches to assessing the environmental safety of territories located near construction industry enterprises are analyzed: cement plants, factories for the production of concrete and reinforced concrete structures. Threats to the ecological safety of built-up landscape that adjoin them have been identified. A structural and logical scheme of means to ensure the environmental safety of construction industry facilities and adjacent territories has been developed. It includes monitoring the state of the main components of the physical environment (soils, atmosphere and hydrosphere), assessing threats to the safety of urban residential areas and a system of organizational, technical, managerial and engineering solutions. A conceptual scheme for the environmental safety of urban areas adjacent to factories has been developed, based on the interaction of such main components as scientific substantiation of anthropogenic loads, monitoring of the environment, conservation of landscape and biological diversity, greening of economic activities, provision of environmental services and recreational activities in adjacent areas. Keywords: conceptual scheme, environmental safety, built-up areas of megalopolises, cement plants, ready-mixed concrete and reinforced concrete structures plants.

scholarly journals Study on the effects of green-based plant extracts and water-proofers as anti-corrosion agents for steel-reinforced concrete slabs

2021 ◽  
Vol 302 ◽  
pp. 02018
Author(s):  
Jagadeesh Bhattarai ◽  
Madan Somai ◽  
Nirmal Acharya ◽  
Ajaya Giri ◽  
Akash Roka ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Plant Extracts ◽  
Research Work ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
Corrosion Properties ◽  
Cell Potential ◽  
Positive Direction ◽  
Reinforced Concrete Slabs ◽  
Corrosion Susceptibility

Widespread applications of reinforced concrete structures have been practiced since the 20th century because of their excellent properties despite their early corrosion degradation. For the control of such a problem, a design strategy of corrosion-resistant environments of the reinforced concrete structures is highly desirable for extending of a lifetime. The present research work was focused to investigate the effects of the green plant extract-based inhibitors from Vitex negundo and Catharanthus roseus leaves, and one waterproofing chemical (PtS) for controlling the corrosion susceptibility of concrete rebar using a half-cell potential method following the ASTM C876-91 standard. Both plant extracts have good anti-corrosion properties, and hence could be applied as green concrete additives to increase the corrosion resistance of the steel reinforcing bars. The anti-corrosion performance of the steel rebars in concrete is remarkably higher with the additions of 1000 and 2000 ppm plant extracts than the additions of waterproofing chemicals used, based on the shifting of corrosion potential (ϕcorr.) values to a more positive direction than −126 mV (SCE). The results agreed that both the plant extracts could be promising for the formulation of effective, ecofriendly anti-corrosion additives to delay the corrosion susceptibility of the concrete infrastructures.

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