Open access peer-reviewed chapter

Corrosion Inhibitors for Reinforced Concrete: A Review

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Han-Seung Lee, Velu Saraswathy, Seung-Jun Kwon and Subbiah Karthick

Submitted: June 26th, 2017 Reviewed: November 20th, 2017 Published: December 20th, 2017

DOI: 10.5772/intechopen.72572

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The objective of the topic is to review the recent trends in corrosion inhibitors for reinforced concrete and their application in the laboratory and field conditions. Inhibitors are chemical substances which when added to the concrete in small concentrations will inhibit or prolong the time to initiation of corrosion in concrete structures. This chapter focuses on the type of inhibitors used in concrete based upon their mode of action and the way of application. The section deals with anodic, cathodic, mixed inhibitors; performance of admixed inhibitor vs. migrating/surface applied inhibitor and their evaluation studies; and electrochemical injection of corrosion inhibitor (EICI) in concrete and electrochemical chloride extraction techniques has been reviewed.


  • anodic inhibitors
  • cathodic inhibitors
  • mixed inhibitors
  • organic inhibitors
  • migrating inhibitors
  • electrochemical injection
  • reinforced concrete

1. Introduction

Corrosion of steel in concrete structures plays a significant role in affecting the service life of the concrete structures. Various methods have been developed with the intent of preventing the corrosion and to enhance the service life. The methods include the coating to the concrete surface, the coating to the reinforcement, cathodic protection, electrochemical methods, alternative reinforcement, and corrosion inhibitors. Among all the available techniques, the use of corrosion inhibitors is one of the most appropriate and efficient methods for corrosion protection of reinforced concrete structures due to the easy operation, low cost, and excellent corrosion resistance effect [1, 2, 3, 4, 5, 6, 7, 8]. Inhibitors which are added to the concrete in small concentrations are intended to delay and slow the onset of corrosion in reinforced concrete. Most of the inhibitors act by stabilizing the steel surface by forming the protective film, and some inhibitors react with concrete forming the complex thus reducing the permeability of the concrete. Corrosion inhibitors are generally used as admixtures in concrete for new construction, but they can also be utilized for repairs by admixed with concrete for patches, sprayed onto the surface of the concrete or applied by saturation treatment [9, 10, 11, 12, 13].

As per NACE international, “a corrosion inhibitor is a substance when added to an environment, either continuously or intermittently to prevent corrosion by forming a passive film on the metal.” In other processing industries, inhibitors are the first line of defense against corrosion [14].

Inhibitors slow down the corrosion process by:

  • increasing the anodic or cathodic polarization behavior;

  • reducing the movement of ions of the metallic surface;

  • increasing the electrical resistance of the metallic surface.

1.1. Classification of corrosion inhibitors

Corrosion inhibitors for concrete are classified based on [15, 16, 17, 18] (Figure 1):

  • Electrochemical mechanism of action (anodic or cathodic, or both).

  • Type of chemicals used (organic and inorganic).

  • The way of application; either mixed with concrete or applied on hardened concrete (migrating inhibitors).

Figure 1.

Classification of corrosion inhibitors.

1.2. Anodic (passivating) inhibitors

This type of inhibitors forms an insoluble protective film on anodic surfaces to passivate the steel. An anodic inhibitor shifts the potential to the passivation zone causing the formation of a thin passive film on the anodic sites, which increases the potential of the anode and decrease the corrosion in rate. There are two types of passivating inhibitors.

  • Oxidizing anions, such as chromates, nitrates, and nitrites, passivate the steel in the absence of oxygen.

  • Nonoxidizing ions, such as phosphate, tungstate, and molybdates, require the presence of oxygen to passivate the steel.

Anodic inhibitors are effective only when present in sufficiently high concentrations [15]. Typically, the concentration required is determined by the level of chloride present in the environment in which the steel is exposed. The most commonly used anodic inhibitor for concrete is calcium nitrite [18]. Calcium nitrates show similar inhibiting properties in concrete. Some anodic inhibitors, such as nitrites, cause accelerated corrosion and pitting if the concentration drops below the threshold/critical level [19]. Nitrates, benzoates, chromates, molybdates, and orthophosphates are used as anodic inhibitors.

1.3. Cathodic inhibitors

Cathodic inhibitors slow down corrosion by reducing the rate of cathodic reactions in the corrosion environment. A cathodic inhibitor causes the formation of insoluble compounds precipitating on the cathodic sites in the form of a barrier film. These inhibitors are called precipitation inhibitors [20]. Zinc and magnesium salts are cathodic inhibitors that form precipitates of zinc hydroxide and magnesium hydroxide at the cathode [21, 22]. Phosphates precipitate as ferrous and ferric phosphates on the steel substrate [23]. Cathodic inhibitors are not as effective as anodic inhibitors, but they are not likely to cause pitting [24].

1.4. Mixed inhibitors

Mixed inhibitors quash both the anodic and cathodic reactions, and they reduce the corrosion rate by forming a thin protective hydrophobic film on entire surface of the metal through adsorption mechanism [25]. The material with the hydrophobic group that has polar groups, such as N, S, and OH, is effective. These inhibitors are called adsorption or film-forming inhibitors [26, 27, 28]. The effectiveness of the film depends on the chemical composition, molecular structure, and their affinities for the metal surface. Cationic inhibitors, such as amines, and anionic inhibitors, such as sulfonates, get adsorbed on the metal surface, whether it is charged positively or negatively. The strength of the bond is the dominant factor for organic inhibitors. Organic inhibitors can also act as pore blockers, reducing the permeability of the concrete. Amines and amino alcohols are the commonly used mixed inhibitors, which displace the chloride ion and form a durable passivating film [29].

Organic inhibitors are further classified into two categories, based upon their application: inhibitor admixed concrete and migrating corrosion inhibitors that are applied on the hardened surface of the concrete [10, 19]. Corrosion inhibitors may be a good alternative for repair concrete due to their lower cost and ease of application. The main application methods for corrosion inhibitors are: added to fresh concrete as an admixture, applied on the hardened concrete and damaged structures migrating corrosion inhibitors (MCI), added to repair mortars, used as a surface treatment to rebars before concreting [10].

1.5. Effect of anodic, cathodic, and mixed inhibitors in concrete

Corrosion of steel in concrete structures is the primary concern when the structures are exposed to the coastal marine environment. The use of corrosion inhibitors can delay the onset of chloride-induced corrosion, prolong the time to initiation of corrosion, and thereby reduce the corrosion rate [30, 31]. Calcium nitrite is the most commonly used anodic corrosion inhibitor for reinforced concrete. This inhibitor is a passivating inhibitor, which forms a passive film on the surface of steel and significantly reduces the corrosion rate of steel in chloride-contaminated concrete [1, 32]. The inhibitive action of steel with calcium nitrite is as follows [1, 10]:


Different authors have reported different threshold value threshold [Cl]/[NO2] ratio depends on the environment. It was reported that the re-passivation of the corroded steel was observed at the [Cl]/[NO2] ratio from 0.5 to 1 [32]. For chloride-contaminated concrete or mortar, the [Cl]/[NO2] ratio ranges from 1 to 3, and for simulated alkaline solutions and chloride-contaminated concrete, the [Cl]/[NO2] ratio ranges from 1 to 4 [3, 31]. Several laboratory studies have established the performance of calcium nitrite as an efficient corrosion inhibitor [1, 10, 15, 27, 33]. But, at the same time, possible increase of corrosion rate in case of low dosage or the presence of cracks [16]. Also, increase in dosage resulted in a decrease of the setting time and lowers the compressive strength of concrete and corrosion process may get accelerated [10, 32]. However, their application in corrosion protection is limited due to its toxicity and carcinogenicity [6, 34]. Chromates are carcinogenic, and hence its use is also prohibited [35, 36]. Haleem et al. [37] investigated the pitting corrosion behavior of phosphates, tungstate, and molybdates in chloride-contaminated Ca(OH)2 solution and found that pitting corrosion current reaches steady state values, which depend on the way of introducing the inhibiting anions in the solution. Studies revealed that sodium phosphate forms a protective layer on the surface of the steel in chloride-contaminated synthetic concrete pore solution. Besides pretreatment of steel with 0.5 M inhibitor solution for 72 h forms a protective layer which further enhanced the protection efficiency [38, 39, 40, 41]. Nahali et al. [42] studied the effect of Na3PO4 addition in chloride-contaminated mortar and concluded that the addition of phosphate inhibitor in concrete decreases the chloride ions effect on localized corrosion.

Yohai et al. [43, 44] reported that the phosphate ions behaved as a mixed type inhibitor. Soluble phosphate compounds, such as disodium phosphate or mono fluoro phosphate, can be mixed with mortar or applied on concrete [42] by immersion or by surface application [45]. Song et al. [46] evaluated the role of alkaline nitrites on the inhibition of corrosion of steel in binary (OPC + PPC) and ternary cement (OPC + PPC + PSC) and reported that ternary system provides 81% protection efficiency (Table 1) for steel in concrete in the presence of 3% chloride concentration. Muralidharan et al. [47] evaluated the effect of various inhibitive ions (hydroxide, citrate, and stannate) in chloride-contaminated (OPC + FA) extract and mortar and found that the addition of inhibitive ions decreased the corrosion rate of the steel rebar in simulated concrete environments.

(mV vs. SCE)
Tafel slopes
(mV dec−1)
Corrosion rate (mmpy)Efficiency (%)
Plain +1% Cl−56658880.0042
Plain +2% Cl−57650870.0062
Plain +3% Cl−58058850.0091
Plain +0.5% NO2−53850870.000192
Plain +0.5% NO2 + 1% Cl−54753870.000491
Plain +0.5% NO2+ 2% Cl−55651850.000789
Plain +0.5% NO2+ 3% Cl−56651810.001781

Table 1.

Potentiodynamic polarization parameters for steel in ternary cement extract [45].

Furthermore, the effectiveness of corrosion inhibitors was enhanced by using hybrid corrosion inhibitors; these inhibitors had good corrosion resistance and low toxicity, but the mechanism of protection is not clear [48]. The combined effect of pitting and uniform corrosion on the surface of the rebar was studied by using sodium molybdate (Na2MoO4), cerium nitrate hexahydrate, 2,5 Dimercapto-1,3,4-thiadiazole (DT), 2-Mercaptobenzothiazole (MBT), and 1H-benzotriazole (BTA). All the inhibitors except DT and Na2MoO4 are toxic. From the study, they concluded that Na2MoO4 is the non-toxic inhibitor, which re-passivates the pits formed on the surface of the steel rebar by forming an insoluble FeMoO4 compound [36]. Saraswathy et al. [1] and Song et al. [15] studied the effect of anodic, cathodic, and mixed inhibitors in concrete by conducting various short- and long-term accelerated techniques. They concluded that the mixed inhibitor had shown higher time to cracking (Figure 2), lower coulomb values (Figure 3), higher compressive strength (Figure 4), and lesser corrosion rate (Tables 2 and 3).

Figure 2.

Impressed voltage test [1].

Figure 3.

Rapid chloride penetration test [1].

Figure 4.

Compressive strength vs. percentage of inhibitors.

SystemsCorrosion rate (mmpy)

Table 2.

Corrosion rate of rebar exposed to various types of inhibitors admixed with chloride [1].

Tafel slopes
(mV dec−1)
Corrosion rate (mmpy)
OPC - Control−5808035020.50.240
NaNO2 1%−4401102602.510.029
ZnO 1%−4401153001.350.015
Mixed 1%−4201802250.900.010
Triethanolamine 1%−4701102924.520.052
Monoethanolamine 1%−5108330610.50.121
Diethanolamine 1%−5009040013.40.155

Table 3.

Potentiodynamic polarization parameters for mild steel in concrete containing different inhibitors [15].


2. Effect of organic inhibitors in concrete

2.1. Admixed vs. migrating corrosion inhibitors (MCI)

Recently, organic inhibitors gained more attraction in the construction industry due to their promising application as admixtures in reinforced concrete with improved protection efficiency and low cost [49]. Organic inhibitors are used as an admixed corrosion inhibitor [13, 18] or migrating corrosion inhibitors (MCI) [18, 50, 51, 52]. Migrating inhibitors are also called as surface applied inhibitors. Both admixed and migrating corrosion inhibitors prevent steel corrosion by forming a thin layer of protective barrier film on the surface of the rebar through adsorption mechanism. Amines and alkanol amines [1, 52, 53, 54] and their salts are used as organic inhibitors in concrete. It has been reported that the alkanol amine-based inhibitors could be able to decrease the corrosion rate of the carbonation induced corrosion effect only for the chloride-induced corrosion of reinforcement [55]. Furthermore, the results indicated that penetrating corrosion inhibitors when applied to the surface of existing or new structures can able to reduce the corrosion rate below 0.1 μA/cm2. Organic inhibitors can adsorb by chemisorption or physisorption. Chemisorption leads to the chemical reaction between active centers of corrosion onto metal and organic inhibitor, where charges from the polar group of inhibitor and charges from metal and metal oxides formed in concrete are shared. Then, organic inhibitor forms the thin coating film blocking the metal surface from the aggressive species by strong chemical bonds. Physisorption leads to the formation of a mechanical barrier, made by organic inhibitors [56]. This inhibitor can halt both the anodic and cathodic reactions, thus reducing the corrosion rate of the reinforcing steel [57]. It has been reported that carboxylate and amino alcohol-based corrosion inhibitors show dual actions in concrete as the amines and alkanol amines adsorb on the metal surface and form a protective film against chloride [58, 59], whereas the carboxylate ester compound reacts with calcium hydroxide, precipitates and blocks the pores of the concrete. This pore blocking property is said to be a secondary protection mechanism against reinforcement corrosion [16, 18, 44, 58]. Furthermore, another study reported that some organic inhibitors adsorb better on the iron surface in the active state than in the passive state [60]. Ormellese et al. [61] reported that amines and alkanol amines (Table 4) had poor corrosion inhibition effect on steel in chloride containing alkaline solutions. They further observed that polycarboxylates are more efficient against pitting corrosion. Comparison of carboxylates with amines/alkanol amines and amino acids were investigated in the same study, and the results are summarized in Predeferri’s diagram showing pitting potential vs. chloride concentration (Figure 5). From the figure, it is evident that amines/alkanol amines had only moderate effectiveness, while carboxylates showed the best behavior at low and medium chloride levels. It was reported that amines were reported to reduce the compressive strength of cement paste and the reducing effect increased with increasing dosage [62]. Heren et al. [63] showed that the decline in concrete strength was enhanced by an increase in corrosion inhibitor concentration.

Amines [61]Carboxylic acids [66]
MethylamineCH3–NH2Sodium gluconate
Dimethylamine(CH3)2–NHD-Saccharic acid, monopotassium salt
EthylamineCH3CH2–NH2Calcium α-D Eptagluconate
PropylamineCH3CH2CH2–NH2Phthalic acid, monopotassium salt
CyclohexylamineC6H11–NH2Lactic acid
TriethylentetramineNH2–CH2CH2–(NHCH2CH2)2–NH2Maleic acid
HexamethylentetramineC6H12N4Suberic acid
AlkanolaminesAdipic acid
Monoethanolamine(OHCH2CH2)–NH2Sodium benzoate

Table 4.

Various amines and alkanolamines investigated by Ormellese et al. [61] and Monticelli et al. [66].

Figure 5.

Pedeferri type diagram showing pitting potential vs. chloride ions and the range of corrosion organic inhibitors [61].

Surface-applied migrating corrosion inhibitors (MCI) are suitable for repairing the chloride-contaminated concrete. In concrete, chloride and inhibitor ions work on three mechanisms: natural diffusion, electrical migration, and transport by movement of pore solution due to the capillary suction or pressure gradient. MCIs are typically based on commercial organic compounds. Aminoalcohols rapidly penetrates through the pores of the concrete, and it protects the steel rebar by forming a hydrophobic layer by physical or chemical adsorption. Another function of this inhibitor is, it reacts with the cement particles and forms an insoluble compound blocking the pores of the concrete [58]. This type of inhibitors is an appropriate strategy to rehabilitate reinforced concrete structures because of its ease of operation, low cost, and safety. MCIs are topically applied to the chloride-contaminated concrete surfaces before placement of the patches and overlays [64]. Zheng et al. [7] studied the durability of the surface applied inhibitor in concrete by conducting various accelerated tests and concluded that the durability of the concrete is improved. Criado et al. [65] examined the surface applied corrosion inhibitors in mortars with fly-ash additives. Another study has shown that amino alcohol-based inhibitors are most effective on the reference mortar specimens than on the specimens with ladle furnace slag. Further, it was noted that the corrosion rate was lowered in the samples with lesser chloride percentage, but was not effective with higher chloride ion containing mortar specimens [66].

Organic MCIs are mostly mixed inhibitors. It creates a hydrophobic layer that helps to repel moisture away from the steel rebar [67]. Monticelli et al. [68] investigated the different type of inhibitors based on amine/alkanol amine and carboxylate (dicarboxylic and hydrocarboxylic acids) on steel corrosion behavior in saturated calcium hydroxide solution containing 0.1 M chloride and chloride admixed mortar. They concluded that among the inhibitors studied, dicyclohexylammonium nitrite seems to be a better inhibitor than dicyclohexylamine. Further, they found that maleic acid was efficient in increasing the pitting potential of the steel in chloride-contaminated alkaline solutions. Of all the acids tested, maleic acid failed to hinder the corrosion process during longer exposure in mortars as like sodium nitrite. However, there is some controversy regarding their use. Elsener et al. [69] reported that amines/alkanol amines are not effective against chloride-induced corrosion. Most of the problems related to low effectiveness have been associated with leaching and evaporation of AMAs volatile components [70, 71] leading to decrease the inhibitor effective concentration in concrete.

Thangavel et al. [72] studied the effect of migrating vs. admixed corrosion inhibitors for steel in Portland, pozzolana, and slag cement concretes under macrocell condition. Macrocell corrosion parameters such as anode potential, macrocell current, and the total integrated current were monitored over a period of 1 year. The corrosion rate of the steel rebar embedded in different types of cement concretes was assessed by gravimetric weight loss method. The admixed inhibitor consists of 0.5% sodium citrate +0.5% sodium stannate and migrating inhibitor consisted of 0.5% amino alcohol, 0.5% amines and 0.5% nitrites. Table 4 shows the various types of inhibitor combinations studied. The authors have concluded that MCI performed better than the admixed system in all the three types of cement used. Among the three types of cement, PSC showed lowest corrosion rate (Table 5). MCI showed 60% reduction in macrocell current (Figures 68) and admixed system showed 40% reduction in macrocell current in PSC concrete.

SystemsAlkalinity (pH)Free chloride contents (ppm)Corrosion rate (mmpy)

Table 5.

Corrosion rate of steel in OPC, PPC and PSC concretes [73].

Figure 6.

Macrocell current vs. number of cycles of exposure for steel in OPC concrete under macrocell condition [72].

Figure 7.

Macrocell current vs. number of cycles of exposure for steel in PPC concrete under macrocell condition [72].

Figure 8.

Macrocell current vs. number of cycles of exposure for steel in PSC concrete under macrocell condition [72].

2.2. Electrochemical injection of corrosion inhibitors (EICI)

Several methods of repair treatments are adopted in the rehabilitation of concrete structures. They are a partial replacement of concrete cover, electrochemical re-alkalization, electrochemical chloride extraction, cathodic protection, and surface application of corrosion inhibitors [73, 74, 75]. Electrochemical injection of corrosion inhibitors (EICI) was found to be an efficient corrosion mitigation technique for carbonated and chloride-contaminated reinforced concrete structures to improve the durability. In EICI, a current density of 1–5 A m−2 is usually applied between the embedded steel cathode and an externally placed anode on the concrete surface in an aqueous solution containing inhibitors for a few weeks [76]. During the application of current, the cationic species of the corrosion inhibitor migrate into the concrete cover to the cathode, whereas the chloride ions in the concrete migrate out of the concrete towards the external anode [73, 76]. EICI was found be an effective method of preventing corrosion in existing structures; and this method serves as a rehabilitative measure to retard or reduce corrosion. Kubo et al. [77] applied the EICI technique in a 40-year-old carbonated reinforced concrete railway viaduct in Tokyo. They tried the electrochemical injection of the organic base corrosion inhibitor, ethanolamine into an existing aged carbonated concrete was found to allow penetration of an adequate concentration of the inhibitor near the steel. It was found that pH near the steel was changed due to the buffering action of the inhibitor. It was also found that due to the variation in the concrete cover (as is usually the case in real concrete structures) the current density distribution was affected resulting in an uneven injection treatment. Further, it was reported that detailed information on the distribution of concrete cover within the structure is therefore needed to establish a reasonable treatment plan for successful inhibitor injection.

Mangayarkarasi et al. [78] studied the efficiency of the electrochemical injection of inhibitors in chloride admixed concrete with OPC, PPC, and PSC concrete by using electrochemical techniques. The inhibitor consists of 0.1 M guanidine, 0.1 M thiosemicarbazide, 2 M triethanolamine, and 2 M ethyl acetate. They concluded the multi-component inhibitor injection showed more than 95% efficiency (Table 6) in terms of reduction in corrosion rate irrespective of chloride levels in different concretes at a current density of 0.5 A/m2. Karthick et al. [2] investigated the EICI by using the same type of inhibitor in a chloride-contaminated old concrete slab (Figure 9) at a current density of 0.5 A/m2. The efficiency of the inhibitor formulation was evaluated through various electrochemical tests, and the mechanism of inhibition was established by FTIR, SEM, EDAX, and MIP studies. They found that FTIR studies (Figure 10) indicated that the functional group of the inhibitors namely –NH2, C–H, and C≡C move towards the cathode of embedded rebar and adsorbed on the metal surface and thereby provided inhibition. MIP studies (Figure 11) proved that nearly 50% reduction in porosity was observed for concrete samples after EICI. SEM analysis (Figure 12) indicated that the hybrid inhibitor formulation act as a pore blocking agent. They also found that the EICI treatment can shift the rebar potential (+300 mV) towards the passive region in the potentiodynamic polarization curve (Figure 13) with the result the corrosion rate of the rebar also reduced considerably.

Figure 9.

Schematic representation of electrochemical EICI process in concrete [2].

Figure 10.

FTIR spectroscopy for concrete—before and after EI [2].

Figure 11.

Mercury intrusion porosity for before and after EI process for concrete [2].

Figure 12.

SEM images for concrete before and after EI [2].

Figure 13.

Potentiodynamic polarization curve for rebar in concrete before and after EI [2].

SystemCementEcorr (mV vs. SCE)Icorr (−2) × 10−5Corrosion rate (mmpy) × 10−3Inhibitor efficiency (%)
Without electro injectionOPC−59191.91010.650
With electro injectionOPC−2826.0340.69993.43

Table 6.

Polarization parameters for the corrosion of rebar embedded in OPC, PPC, and PSC concretes with and without electro injection process [79].

Pan et al. [79] evaluated the inhibition efficiency of eight organic inhibitors by monitoring the corrosion rate steel in aggressive, simulated concrete pore solution through electrochemical injection method. The data showed that tetrabutylammonium bromide (TBA-B) and tetramethylammonium chloride (TMA-C) outperformed other chemicals as corrosion inhibitors in the simulated concrete pore solution, by reducing the corrosion rate of steel by 85 and 75%, respectively. Nguyen et al. [80] performed the EICI rehabilitation treatments in repair mortar with tetra butyl ammonium bromide salt at a current density of 5 A/m2, by using two electrolytes of 0.1 M NaOH and Na3BO3 for 1 and 4 weeks, respectively. The results reveal that the EICI treatment with 0.1 M Na3BO3 was more efficient in improving the chloride penetration resistance and the compressive strength of the mortar, relative to 0.1 M NaOH as the electrolyte.

Liu and Shi [81] presented a state of the art report on electrochemical chloride extraction (ECE) and EICI, which covers the laboratory studies and computational models to predict the kinetics of ECE and EICI. Sawada et al. [76] evaluated ethanolamine and guanidine, the two organic inhibitors for steel, in aqueous media by immersing the carbonated and non-carbonated concrete and impressing a current density of 1–5 A/m2 for 3–14 days. It was found that the efficiency was far higher in carbonated concrete than in non-carbonated concrete and that, in the carbonated specimens, the inhibitors became concentrated near the embedded steel. In non-carbonated concrete, guanidine penetration was accelerated, but the ethanolamine penetration was not significantly enhanced by the application of current density.

Xu et al. [54] adopted a novel method called bi-directional electromigration rehabilitation [BIEM] for injecting the corrosion inhibitor (triethylenetetramine) into chloride-contaminated concrete specimens. In this process, an electric field was applied between the embedded steel cathode and external anode to inject the inhibitor from an external electrolyte to the concrete specimens and extract the chloride ions from the cover zone concrete. After the treatment, the specimens were drilled to determine the concentration profiles of the corrosion inhibitor, chloride, and hydroxyl ions within the concrete. ECE was compared with as a control experiment using saturated Ca(OH)2 solution as an external electrolyte. They found that the chloride content decreased, and alkalinity increased after treatment. The concentration of the inhibitor injected around the embedded steel bars was adequate to provide corrosion protection. Among the electrochemical rehabilitation techniques available, ECE is the most widely used method of repairing chloride-contaminated structures. However, this approach cannot completely remove the chlorides in the structure and is only a temporary solution because chloride ions tend to come back after treatment is stopped [75]. Simultaneous effect of chloride removal and re-passivation of concrete by using nitrite (migrating) inhibitor was tried by the application of ECE treatment. The electrochemical response of the embedded rebar after the ECE treatment was found that the migration of nitrite ions re-passivated the steel surface and the chloride removal efficiency was also increased [82].


3. Summary of inhibitors used

Tables 7 and 8 show the review of the most commonly used corrosion inhibitor dosage in concrete. From the table, it is evident that recently organic inhibitors are mainly focused and most of the studies are carried out in simulated concrete pore solution containing chloride. Only a few studies are conducted in mortar and concrete. Very fewer field studies are undertaken.

ReferenceInhibitor usedDosageEnvironment
Jiang et al. [6]Deoxyribonucleic acid as a biological corrosion inhibitor0.0025%Simulated concrete pore solution
Zheng et al. [7]Organic inhibitors—surface appliedConcrete
Diamanti et al. [22]Organic inhibitors0.0001, 0.001, 0.01, and 0.1 MConcrete pore solution
Xu et al. [33]Anodic, cathodic, and mixed inhibitors1, 2% by vol.Simulated environment
Nahali et al. [41]Na3PO4Mortar +Cl
Yohai et al. [42]Na3PO4Mortar +Cl
Fei et al. [47]Cathodic inhibitorPore solution
Verbuggen et al. [48]Organic inhibitors10−4 MConcrete pore solution
Ormellese et al. [50]Organic inhibitors/Migrating0.3 mol/LConcrete pore solution
Shi et al. [52]Migrating corrosion inhibitorMortar
Xu et al. [54]Organic inhibitors—electro-injection
Criado et al. [66]Organic inhibitors0.05 MActivated fly ash mortar
Prieto et al. [67]Organic inhibitors—surface applied0.500 kg/m2Mortar
Cabrini et al. [68]Organic inhibitors0.1 MPore solution
Kubo et al. [78]Electrochemical injection (Amine based)0.5–2.0 mol/lReal concrete bridge (40-year-old railway viaduct)
Sanchez et al. [82]Electrochemical removal and migration of inhibitorNitriteReinforced concrete

Table 7.

Review of inhibitors in concrete (2010–2017).

Type of inhibitorExposure conditionInhibitorspHDosageEfficiency (%)References
Anodic inhibitorsConcrete admixed 1.96% NaClCa(NO3)26.0–6.50.4926.51[32]
Sat. Ca(OH)2 + 3% NaClNa3PO410.5–11.81 mol/l60.02[38]
2.5 mol/l64.85[38]
5 mol/l78.2[38]
7.5 mol/l80.0[38]
10 mol/l78.1[38]
Concrete immersed in 3% NaClNaNO27.5–8.51%87.9[15]
Cathodic InhibitorsConcrete immersed in 3% NaClZnO6.95–7.81%93.75[15]
Mixed Inhibitors
organic inhibitors
Concrete immersed in 3% NaClNaNO2 + ZnO7.2–8.51%95.8[15]
Concrete immersed in 3% NaClTriethanolamine6.0–7.01%77.04[15]
Concrete immersed in 3% NaClMonoethanolamine11–11.81%49.58[15]
Concrete immersed in 3% NaClDiethanolamine9.8–10.21%35.42[15]
OPC Concrete immersed in 1% NaClDisodium β-glycerol phosphate Pentahydrate + sodium 3-aminobenzoateAdjusted to 7.00.05 M + 0.05 M63[65]
Disodium β-glycerol phosphate pentahydrate + sodium N-phenylanthranilateadjusted to 7.00.05 M + saturated81[65]

Table 8.

Different type of inhibitor dosage in concrete.


4. Conclusions

The following conclusions were drawn:

  • The review focused only on the use of various types of inhibitors in concrete under laboratory and field condition.

  • The corrosion inhibitors are effective in preventing reinforcement from corrosion within concrete structures.

  • The corrosion inhibitor forms a protective film around the embedded steel bars.

  • The inhibitors for concrete are classified as an anodic, cathodic, and mixed type of inhibitors based on the mode of action.

  • Recently, mixed and organic types of inhibitors are the most commonly used inhibitors in concrete due to their synergistic effect.

  • Organic corrosion inhibitors were ineffective in preventing steel corrosion when their concentrations were too low [19]. The corrosion inhibitors can provide adequate protection for reinforcement only when the concentration of the inhibitor is higher than that of the chloride ions in the pore solution [54].

  • Some inhibitors get leached out over an extended period of exposure.

  • Over dosage of inhibitors will cause pitting, leaching, and retarding effect.

  • While under dosage of inhibitor may lead to inefficient protection of the steel rebars.

  • The efficiency of the inhibitor strongly depends on the initial chloride ions concentration in concrete.

  • The performance of the inhibitor strongly depends on the quality of concrete.

  • Amines-, alkanol amines-, and carboxylate-based mixed inhibitors are mostly used in reinforced concrete.

  • Amines and alkanol amines are capable of diffusing through concrete when applied on the surfaces of the structures by capillary action.

  • Migrating inhibitors play a significant role in the repair and rehabilitation of damaged and chloride-contaminated concrete structures.

  • Migrating or surface applied inhibitors are found to be the cost-effective treatment for field implementation due to the ease of application. For this type of application, penetrating type amine/carboxylic-based inhibitors are preferable.

  • The surface-applied inhibitors can penetrate up to the depth of the embedded steel reinforcement; thus, adequate concentrations are necessary to provide corrosion protection when the concrete cover is too thick, or the concrete compaction is too high [83].

  • Electrochemical injection of corrosion inhibitors (EICI) is found to be an effective corrosion mitigation technique for carbonated and chloride-contaminated reinforced concrete structures to improve the durability.

  • In this type of repair method, continuous monitoring of the condition of steel is essential not only in the electrochemically treated area but also in its adjacent regions.

  • Still, the mechanism of mixed/organic inhibitors is not very well understood in long-term applications. Hence, it needs more extensive investigation in real concrete structures by considering the various aspects, such as chloride content, types of cement, types of inhibitors, etc.



This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, & Future Planning (No. 2015R1A5A1037548). One of the authors (V.S.) thanks the Director, CECRI, and CSIR for the permission to pursue my fellowship at Hanyang University, Korea.


  1. 1. Saraswathy V, Song H-w. Improving the durability of concrete by using inhibitors, Building and Environment. Building and Environment. 2007;42(1):464-472. DOI: 10.1016/j.buildenv.2005.08.003
  2. 2. Karthick SP, Madhavamayandi A, Murlidharan S, Saraswathy V. Electrochemical process to improve the durability of concrete structures. Journal of Building Engineering. 2016;7:273-280. DOI: 10.1016/j.jobe.2016.07.005
  3. 3. Krolikowski A, Kuziak J. Impedance study on calcium nitrite as a penetrating corrosion inhibitor for the steel in concrete. Electrochimica Acta. 2011;56(23):7845-7853. DOI:
  4. 4. Vamisi Priya P, Siva Prasad Rao N. Comparative study on various methods used for corrosion protection of rebar in concrete. International journal of Applied Research. 2017;3(1):426-431. DOI:
  5. 5. Christodoulou C, Glass G, Webb J, Austin S, Goodier C. Assessing the long-term benefits of impressed current cathodic protection. Corrosion Science. 2010;52(8):2671-2679. DOI:
  6. 6. Jiang SB, Jiang LH, Wang ZY, Shuya Bai MJ, Song S, Yan X. Deoxyribonucleic acid as an inhibitor for chloride-induced corrosion of reinforcing steel in simulated concrete pore solutions. Construction and Building Materials. 2017;150:238-247. DOI: 10.1016/j.conbuildmat.2017.05.157
  7. 7. Zheng H, Li W, Ma F, Kong Q. The effect of a surface applied corrosion inhibitor on the durability of concrete. Construction and Building Materials. 2012;37:36-40. DOI: 10.1016/j.conbuildmat.2012.07.007
  8. 8. El-Hacha R, Mirmiran A, Cook A, Rizkalla S. Effectiveness of surface-applied corrosion inhibitors for concrete bridges. Journal of Materials in Civil Engnieering. 2011;23(3):271-280. DOI: 10.1061/(ASCE)MT.1943-5533.0000163
  9. 9. De Schutte Gr, Luo L. Effect of corrosion inhibiting admixtures on concrete properties. Construction and Building Materials. 2004;18(7):483-489. DOI: 10.1016/j.conbuildmat2004.04.001
  10. 10. Soylev TA, Richardson MG. Corrosion inhibitors for steel in concrete; state-of-the art report. Construction and Building Materials. 2008;22(4):609-622. DOI: 10.1016/j.conbuildmat.2006.10.013
  11. 11. Martínez I, Andrade C, Castellote M, De Viedma GP. Advancements in non-destructive control of efficiency of electrochemical repair techniques. Corrosion Engineering, Science and Technology. 2008;44(2):108-118. DOI: 10.1179/174327808X286266
  12. 12. Pritzl MD, Tabatabai H, Ghorbanpoor A. Long-term chloride profiles in bridge decks treated with the penetrating sealer or corrosion inhibitors. Construction and Building Materials. 2015;101(1):1037-1046. DOI: 10.1016/j.conbuildmat.2015.10.158
  13. 13. Angst UM, Büchler MM, Schlumpf J, Marazzani B. An organic corrosion-inhibiting admixture for reinforced concrete: 18 years of field experience. Materials and Structures. 2016;49(7):2807-2818. DOI: 10.1617/s11527-015-0687-2
  14. 14.
  15. 15. Song H-W, Saraswathy V. Analysis of corrosion resistance behavior of inhibitors in concrete using electrochemical techniques. Metals and Materials International. 2006;12(4):323-329. DOI: 10.1007/BF03027549
  16. 16. Vyrides I, Rakanta E, Zafeiropoulou T, George BG. Efficiency of amino alcohols as corrosion inhibitors in reinforced concrete. Open Journal of Civil Engineering. 2013;3(2A):1-8. DOI: 10.4236/ojce.2013.32A001
  17. 17. Ormellese M, Berra M, Bolzoni F, Pastore T. Corrosion inhibitors for chlorides induced corrosion in reinforced concrete structures. Cement and Concrete Research. 2006;36(3):536-547. DOI: 10.1016/j.cemconres.2005.11.007
  18. 18. Gaidis MJ. Chemistry of corrosion inhibitors. Cement and Concrete Composites. 2004;26(3):181-189. DOI: 10.1016/S0958-9465(03)00037-4
  19. 19. Justnes H. Preventing chloride induced rebar corrosion by anodic inhibitors—Comparing calcium nitrate with calcium nitrite. In: 29th Conference on our World in Concrete & Structures; 25-26 August, 2004; Singapore. CI-Premier PTE LTD; 2004. pp. 44-58. DOI:
  20. 20. Koch GH, MPH B, Thompson NG, Virmani YP, Payer JH. Corrosion costs and preventive strategies in the United States. Houston: NACE Publications; 2004. p. 12. DOI:
  21. 21. Heiyantuduwa R, Alexander MG, Mackechnie JR. Performance of a penetrating corrosion inhibitor in concrete affected by carbonation induced corrosion. Journal of Materials in Civil Engineering. 2006;18(6):842-850. DOI: 10.1061/(ASCE)0899-1561(2006)18:6(842)
  22. 22. Baiqing Z, Xiaowei W, Qin L, Yisheng P. Performance and mechanism of a water stabilizer for low hardness cooling water. Anti-Corrosion Methods and Materials. 2003;505:347-351
  23. 23. Gallant D, Simard S. A study on the localized corrosion of cobalt in bicarbonate solutions containing halide ions. Corrosion Science. 2005;47(7):1810-1838. DOI: 10.1016/j.corsci.2004.08.008
  24. 24. Davis JR. Corrosion: Understanding the Basics. Materials Park, OH, USA:ASM International; 2000. p. 563. ISBN: 978-0-87170-641-6
  25. 25. Kondratova IL, Montes P, Bremner TW. Natural marine exposure results for reinforced concrete slabs with corrosion inhibitors. Cement and Concrete Composites. 2003;25(4-5):483-490. DOI: 10.1016/S0958-9465(02)00088-4
  26. 26. Elsener B. Mixed-in inhibitors. In: COST 521: Corrosion of Steel in Reinforced Concrete Structures. Prevention–Monitoring–Maintenance, Final Report; Weydert R. editor. 18-19 February; Luxembourg. 2002. pp. 43-55
  27. 27. Soeda K, Ichimura T. Present state of corrosion inhibitors in Japan. Cement and Concrete Composites. 2003;25(1):117-122. DOI: 10.1016/S0958-9465(01)00058-0
  28. 28. Hansson CM, Mammoliti L, Hope BB. Corrosion inhibitors in concrete—Part 1: The principles. Cement and Concrete Research. 1998; 28:1775-1781. DOI: 10.5772/57255
  29. 29. Jamil, HE, Shriri A, Boulif R, Montemor MF, Ferreira MGS. Corrosion behaviour of reinforcing steel exposed to an amino alcohol based corrosion inhibitor. Cement and Composites. 2005;27(6):671-678. DOI: 10.1016/j.cemconcomp.2004.09.019
  30. 30. Elsener B, Angst U. 14 - Corrosion inhibitors for reinforced concrete. In: Aïtcin PC, Flatt RJ, editor. Science and Technology of Concrete Admixtures. 1st ed. Elsevier, Woodhead Publishing, 2016. pp. 321-339. ISBN 9780081006931,
  31. 31. Elsener B. Corrosion Inhibitors for Steel in Concrete-State of the Art Report. European Federation of Corrosion and Institute of Materials, The University of Virginia, European Federation of Corrosion; 2001. p. 68. ISBN: 9781902653488, DOI:
  32. 32. Ann KY, Jung HS, Kim HS, Kim SS, Moon HY. Effect of calcium-nitrite based corrosion inhibitor in preventing corrosion of embedded steel in concrete. Cement and Concrete Research. 2006;36(3):530-535. DOI: 10.1016/j.cemconres.2005.09.003
  33. 33. Xu JX, Jiang H, Wang WL, Tang L, Cui Li. Effectiveness of inhibitors in increasing chloride threshold value for steel corrosion. Water Science and Engineering. 2013;6(3):354-363. DOI: 10.3882/j.issn.1674-2370.2013.03.011
  34. 34. Zhou X, Yang H, Wang F. [BMIM]BF4 ionic liquids as effective inhibitor for carbon steel in alkaline chloride solution. Electrochimica Acta. 2011;56(11):4268-4275. DOI: 10.1016/j.electacta.2011.01.081
  35. 35. European Union Risk Assessment Report. ECHA Member State Committee Draft Support Document for Identification of Boric Acid as a Substance of Very High Concern Because of Its CMR Properties, SVHC Support [Internet]. Available from: [Accessed: 9 June, 2010]
  36. 36. Verbruggen H, Terryn H, Graeve ID. Inhibitor evaluation in different concrete pore solution for the protection of steel rebars. Construction and Building Materials. 2016;124:887-896. DOI: 10.1016/j.conbuildmat.2016.07.115
  37. 37. Abd El Haleem SM, Abd El Wanees S, Abd El Aal EE, Diab A. Environmental factors affecting the corrosion behaviour of reinforcing steel. Variation in pitting corrosion current in relation to the concentration of the aggressive and inhibitive ions. Corrosion Science. 2010;52(5):1675-1683. DOI: 10.1016/j.corsci.2010.01.021
  38. 38. Sail L, Ghomari F, Khelidj A, Bezzar A, Benali O. The effect of phosphate corrosion inhibitor on steel in synthetic concrete pore solutions. Advances in Materials Research. 2013;2(3):155-172. DOI:
  39. 39. Dhouibi L, Triki E, Salta M, Rodrigues P, Raharinaivo A. Studies on corrosion inhibition of steel reinforcement by phosphate and nitrite. Materials and Structures. 2003;36(8):530-540. DOI: 10.1007/BF02480830
  40. 40. Etteyeb N, Sanchez M, Dhouibi L, Alonso C, Andrade C, Triki E. Corrosion protection of steel reinforcement by a pre-treatment phosphate solution. Assessment of passivity by electrochemical techniques. Corrosion Engineering Science and Technology. 2006;41(4):336-341. DOI: 10.1179/174327806X120775
  41. 41. Etteyeb N, Dhouibi L, Takenouti H, Alonso MC, Triki E. Corrosion inhibition of carbon steel in alkaline chloride media by Na3PO4. Electrochimica Acta. 2007;52(27):7506-7512. DOI: 10.1016/j.electacta.2007.03.003
  42. 42. Nahali N, Dhouibi L, Idrissi H. Effect of Na3PO4 addition in mortar on steel reinforcement corrosion behavior in 3% NaCl solution. Construction and Building Materials. 2015;78:92-101. DOI: 10.1016/j.conbuildmat.2014.12.099
  43. 43. Yohai L, Vazquez M, Valcarce MB. Phosphate ions as corrosion inhibitors for steel in chloride-rich environments. Electrochimica Acta. 2013;102:88-96. DOI: 10.1016/j.electacta.2013.03.180
  44. 44. Yohai L, Valcarce MB, Vazquez M. Testing phosphate ions as corrosion inhibitors for construction steel in mortars. Electrochimica Acta. 2016;202:316-324. DOI: 10.1016/j.electacta.2015.12.124
  45. 45. Tritthart J. Transport of a surface-applied corrosion inhibitor in cement paste and concrete. Cement and Concrete Ressearch. 2003;33(6):829-834. DOI: 10.1016/S0008-8846(02)01067-0
  46. 46. Song H-W, Saraswathy V, Muralidharan S, Lee CH, Thangavel K. Role of alkaline nitrites in the corrosion performance of steel in composite cements. Journal of Applied Electrochemistry. 2009;39(1):15-22. DOI: 10.1007/s10800-008-9632-1
  47. 47. Muralidharan S, Saraswathy V, Thangavel K, Srinivasan S. Competitive role of inhibitive and aggressive ions in the corrosion of steel in concrete. Journal of Applied Electrochemistry. 2000;30(11):1255-1259. DOI: 10.1023/A:1026570120698
  48. 48. Fei FL, Hu J, Wei JX, Yu QJ, Chen ZS. Corrosion performance of steel reinforcement in simulated concrete pore solutions in the presence of imidazole quaternary ammonium salt corrosion inhibitor. Construction and Building Materials. 2014;70:43-53. DOI: 10.1016/j.conbuildmat.2014.07.082
  49. 49. Osial M, Wiliński D. Organic substances as corrosion inhibitors for steel in concrete—An overview. Journal of Building Chemistry. 2016;1:42-53. DOI: 10.17461/j.buildchem.2016.107
  50. 50. Ormellese M, Bolzoni F, Goidanich LS, Pedeferri MP, Brenna A. Corrosion inhibitors in reinforced concrete structures. Part 3—Migration of inhibitors into concrete. Corrosion Engineering, Science and Technology. 2011;46(4):334-339. DOI: 10.1179/174327809X419230
  51. 51. Dariva CG, Galio AF. Corrosion Inhibitors-Principles, Mechanisms and Applications. In: Aliofkhazraei M, editor. Developments in Corrosion Protection. UK: InTech; 2014. pp. 365-380. DOI: 10.5772/57010.
  52. 52. Shi W, Wang T-Z, Dong Z-H, Guo XP. Application of wire beam electrode technique to investigate the migrating behavior of corrosion inhibitors in mortar. Construction and Building Materials. 2017;134:167-175. DOI: 10.1016/j.conbuildmat.2016.12.036
  53. 53. Liu JZ, Zhao D, Cai JS, Shi L, Liu JP. Aryl aminoalcohols as corrosion inhibitors for carbon steel in chloride-contaminated simulated concrete pore solution. International Journal of Electrochemical Science. 2016;11:1135-1151
  54. 54. Xu C, Jin WL, Wang HL, HT W, Huang N, Li ZY, Mao JH. Organic corrosion inhibitor of triethylenetetramine into chloride contamination concrete by electro-injection method. Construction and Building Materials. 2016;115:602-617. DOI: 10.1016/j.conbuildmat.2016.04.076
  55. 55. Paredes MA, Carvallo AA, Kessler R, Virmani YP, Sagues AA. Corrosion Inhibitor in Concrete—Second Interim Report, Federal Highway Administration, Department of Transportation, State of Florida, 2010; p. 345.
  56. 56. Ormellese M, Perez EA, Raffaini G, Ganazzoli F, Lazzari L. Inhibition mechanism in concrete by organic substances: An experimental and theoretical study. Journal of Materials Science and Engineering. 2010;4(10):66-77
  57. 57. Wombacher F, Maeder U, Marazzani B. Aminoalcohol based mixed corrosion inhibitors. Cement and Concrete Research. 2004;26(3):209-216. DOI: 10.1016/S0958-9465(03)00040-4
  58. 58. Soylev TA, McNally C, Richardson M. Effectiveness of amino alcohol-based surface-applied corrosion inhibitors in chloride-contaminated concrete. Cement and Concrete Research. 2007;37(6):972-977. DOI: 10.1016/j.cemconres.2007.03.010
  59. 59. Jamil, HE, Shriri A, Boulif R, Bastos C, Montimor MF, Ferreira MGS. Electrochemical behaviour of amino alcohol-based inhibitors used to control corrosion of reinforcing steel. Electrochimica Acta. 2004;49(17-18):2753-2760. DOI: 10.1016/j.electacta.2004.01.041
  60. 60. Olsson C-OA, Agarwal P, Frey M, Landolt D. An XPS study of the adsorption of organic inhibitors on mild steel surfaces. Corrosion Science. 2000;42(7):1197-1211. DOI: 10.1016/S0010-938X(99)00140-7
  61. 61. Ormellese M, Lazzari L, Goidanich S, Fumagalli G, Brenna A. A study of organic substances as inhibitors for chloride-induced corrosion in concrete. Corrosion Science. 2009;51(12):2959-2968. DOI: 10.1016/j.corsci.2009.08.018
  62. 62. Brown MC, Weyers RE, Sprinkel MM. Effects of corrosion-inhibiting admixtures on material properties of concrete. ACI Materials Journal. 2001;98(3):240-250. DOI: 10.14359/10279
  63. 63. Heren Z, Olmez H. The influence of ethanolamines on the hydration and mechanical properties of Portland cement. Cement and Concrete Research. 1996;26(5):701-705. DOI: 10.1016/S0008-8846(96)85007-1
  64. 64. Liu Z, Miao C, Zhou W, Liu J. Maintenance and improvement of durability of reinforced concrete using migrating corrosion inhibitors. Journal of the Chinese Ceramic Society. 2008;36(10):1497-1500
  65. 65. Criado M, Monticelli C, Fajardo S, Gelli D, Grassi V, Bastidas JM. Organic corrosion inhibitor mixtures for reinforcing steel embedded in carbonated alkali-activated fly ash mortar. Construction and Building Materials. 2012;35:30-37. DOI: 10.1016/j.conbuildmat.2012.02.078
  66. 66. Prieto MI, Cobo A, Rodríguez A, Gonzalez MN. The efficiency of surface-applied corrosion inhibitors as a method for the re passivation of corroded reinforcement bars embedded in ladle furnace slag mortars. Construction and Building Materials. 2014;54:70-77. DOI: 10.1016/j.conbuildmat.2013.12.014
  67. 67. Cabrini M, Fontana F, Lorenzi S, Pastore T, Pellegrini S. Effect of organic inhibitors on chloride corrosion of steel rebars in alkaline pore solution. Journal of Chemistry. 2015;2015:521507. DOI: 10.1155/2015/521507
  68. 68. Monticelli C, Frignani A, Trabanelli G. A study on corrosion inhibitors for concrete application. Cement and Concrete Research. 2000;30(4):635-642. DOI: 10.1016/S0008-8846(00)00221-0
  69. 69. Elsener B, Buechler M, Stalger F, Böhni H. Migrating corrosion inhibitor blend for reinforced concrete: Part 2. Inhibitor as repair strategy. Corrosion. 2000;56(7):727-732. DOI: 10.5006/1.3280576
  70. 70. Bavarian B, Reiner L. Migrating corrosion inhibitor protection of steel rebar in concrete. Materials Performance. 2003;42(2):3-5
  71. 71. Jamil, HE, Montemor MF, Boulif R, Shriri A, Ferreira MGS. An electrochemical and analytical approach to the inhibition mechanism of an amino-alcohol-based corrosion inhibitor for reinforced concrete. Electrochimica Acta. 2003;48(23):3509-3518. DOI: 10.1016/S0013-4686(03)00472-9
  72. 72. Thangavel K, Muralidharan S, Saraswathy V, Quraishi MA, Song H-W. Migrating vs admixed corrosion inhibitors for steel in Portland, Pozzolana and slag cement concretes under macro cell condition. The Arabian Journal for Science and Engineering. 2009;34(2C):81-93
  73. 73. NACE SP0107-2007. Electrochemical Realkalization and Chloride Extraction for Reinforced Concrete [Internet]. Available from:
  74. 74. Fajardo G, Escadeillas AG. Electrochemical chloride extraction (ECE) from steel reinforced concrete specimens contaminated by artificia sea-water. Corrosion Science. 2006;48(1):110-125. DOI: 10.1016/j.corsci.2004.11.015
  75. 75. Bennett JK, Schue TJ, Clear KC, Lankard DL, Hartt WH, Swiat WJ. Electrochemical Chloride Removal and Protection of Concrete Bridge Components: Laboratory Studies, Report # SHRP S-657 [Internet]. 1993. Available from:
  76. 76. Sawada S, Kubo J, Page CL, Page MM. Electrochemical injection of organic corrosion inhibitors into carbonated cementitious materials: Part I—Effects on pore solution chemistry. Corrosion Science. 2007;49(3):1186-1204. DOI: 10.1016/j.corsci.2006.06.020
  77. 77. Kubo J, Tanaka Y, Page CL, Page MM. Application of electrochemical organic corrosion inhibitor injection to a carbonated reinforced concrete railway viaduct. Construction and Building Materials. 2013;39:2-8. DOI: 10.1016/j.conbuildmat.2012.05.010
  78. 78. Mangayarkarasi G, Muralidharan S. Electrochemical protection of steel in concrete to enhance the service life of concrete structure. Procedia Engineering. 2014;86:615-622. DOI: 10.1016/j.proeng.2014.11.087
  79. 79. Pan T, Nguyen TA, Shi X. Assessment of electrical injection of corrosion inhibitor for corrosion protection of reinforced concrete. Journal of the Transportation. Research Board. 2008;2044:51-60.
  80. 80. Nguyen TH, Nguyen TA, Nguyen TV, Le VK, Dinh TMT, Thai H, Shi X. Effect of electrical injection of corrosion inhibitor on the corrosion of steel rebar in chloride-contaminated repair mortar. International Journal of Corrosion. 2015;2015:862623. DOI: 10.1155/2015/862623
  81. 81. Liu Y, Shi X. Electrochemical chloride extraction and electrochemical injection of corrosion inhibitor in concrete: State of the knowledge. Corrosion Reviews. 2009;27(1-2):53. DOI: 10.1515/CORRREV.2009.27.1-2.53
  82. 82. Sanchez M, Alonso C. Electrochemical chloride removal in reinforced concrete structures: Improvement of effectiveness by simultaneous migration of calcium nitrite. Construction and Building Materials. 2011;25(2):873-878. DOI: 10.1016/j.conbuildmat.2010.06.099
  83. 83. Sawada S, Page CL, Page MM. Electrochemical injection of organic inhibitors into concrete. Corrosion Science. 2005;47(8):2063-2078. DOI: 10.1016/j.corsci.2004.10.001

Written By

Han-Seung Lee, Velu Saraswathy, Seung-Jun Kwon and Subbiah Karthick

Submitted: June 26th, 2017 Reviewed: November 20th, 2017 Published: December 20th, 2017