Research on Chloride Appropriate Dosage for Incorporated Accelerated Corrosion

2014 ◽  
Vol 989-994 ◽  
pp. 458-461
Author(s):  
Qi Xia Liu ◽  
Shu Lin Zhan
Keyword(s):  
Compressive Strength ◽  
Corrosion Potential ◽  
Potential Method ◽  
Polarization Potential ◽  
Half Cell ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Steel Bars ◽  
Corrosion State ◽  
Potential Curves

Mixing chlorine is one of the ways to ensure the theory and practical steel bars corrosion rate closer when mixing concrete for laboratory electrochemical accelerated corrosion and appropriate chloride dosage should guarantee the steel bars are in the critical corrosion state when we start to accelerated corrosion. By comparing the specimens’ experimental compressive strength, chloride-permeation resistance, corrosion potential measured by the half-cell potential method and polarization potential curves measured by the linear polarization potential method with different Nacl dosage, we get the appropriate Nacl dosage is nearly 1.90%, namely cl- content is about 1.15%.

Resistance of Chlorides-Induced Corrosion of Steel Bar Embedded in CNTs-OH Modified Concrete

2018 ◽  
Vol 768 ◽  
pp. 320-325
Author(s):  
Zhong Kun Wang ◽  
Jie Fan ◽  
Geng Ying Li
Keyword(s):  
Corrosion Potential ◽  
Potential Method ◽  
Test Results ◽  
Pore Filling ◽  
Half Cell ◽  
Cell Potential ◽  
Air Interface ◽  
Steel Bar ◽  
Corrosion Of Steel ◽  
Oh Content

Aim of this paper is to evaluate the influence of hydroxyl carbon nanotubes (CNTs-OH) content (by 0.1-0.5% of cement weight) on the resistance of chlorides-induced corrosion of steel bar embedded in concrete. The corrosion process of concrete was monitored by using half-cell potential method (Ecorr, mv CSE). Test results show that the addition of CNTs-OH considerably increased the resistance of rebar chlorides induced corrosion of concrete, and the optimum content of CNTs was about 0.3% by mass of cement. Simultaneously, results also indicate that the measuring position impacted the corrosion potential value, in which the point on the water/air interface had the highest corrosion probability. In addition, the water absorption and SEM of concrete containing CNTs-OH were also investigated, and the pore-filling effect of CNTs-OH was observed to improve the properties of concrete.

Wave amplitude of embedded ultrasonic transducer-based damage monitoring of concrete due to steel bar corrosion

2021 ◽  
pp. 147592172110417
Author(s):  
Shunquan Zhang ◽  
Zijian Jia ◽  
Yuanliang Xiong ◽  
Ruilin Cao ◽  
Yamei Zhang ◽  
...  
Keyword(s):  
Ultrasonic Transducer ◽  
Steel Corrosion ◽  
Galvanic Current ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Electrochemical Testing ◽  
Steel Bar ◽  
Steel Bars ◽  
Damage Process ◽  
Corrosion Of Steel

In this research, four embedded ultrasonic piezoelectric transducers were combined to form cross pair and opposite pair monitoring schemes for continuously monitoring the damage to different strength grades of concrete caused by the corrosion of reinforcements under accelerated corrosion conditions. The damage process was analyzed by combining the electrochemical effects of steel corrosion, that is, half-cell potential and galvanic current tests. Results show that the embedded ultrasonic transducer method can detect damage of concrete during steel corrosion and that each stage of damage can be determined from the plots of ultrasonic transducer data versus corrosion rate. The results further indicate that a combination of cross pair and opposite pair testing methods can more comprehensively reflect the damage to concrete caused by the expansion of corrosion of steel bars, than a single testing method. Since electrochemical testing can only depict the corrosion state of steel rebars, it is beneficial to use embedded ultrasonic measurements to monitor the damage process of concrete. The differences in damage between different strength grades of concrete, that is, the resistance to corrosion of steel bars and brittle failure, can be obtained from the plots of ultrasonic transducer data.

The Tests and Measures of Concrete Ageing and Steel Bar Corrosion of the Salt Free Contaminated Inland Waterlocks

2011 ◽  
Vol 71-78 ◽  
pp. 4525-4532
Author(s):  
Jin Yang Zhang
Keyword(s):  
Concrete Surface ◽  
Potential Method ◽  
Cell Potential ◽  
Railway Bridges ◽  
Hydraulic Concrete ◽  
Steel Bar ◽  
Steel Bars ◽  
Aging Phenomena ◽  
Peeling Off ◽  
Test Result

There are mainly three phenomena, i.e. cracks, infiltration and denuding for judging the aging and defects from hydraulic concrete constructions. The inland waterlocks’ concrete ageing with salt free contamination are found basically the concrete denuding, rebar erosive expansion cracks and concrete surface gravel exposure and freeze thawing peeling-off as well occasionally. The severe aging phenomena always occur in some small structures in work bridges, sub work bridges, railway bridges and concrete waterlocks etc, especially in boundary beams or flange plates of the said beams. The result manifests that the test result is completely in conformity with the actual situation in the test of internal concrete steel bar erosion by means of Eigenvalue K method and half-cell potential method. In order to prevent steel bars in the concrete from eroding and guarantee the durability of waterlocks, currently the treating method used most frequently is the waterlock concrete surface carbonization resistance treatment

scholarly journals The Study of Half-cell Potential Behaviour of Reinforced Concrete in Marine Environment

2021 ◽  
Vol 9 (VII) ◽  
pp. 128-131
Author(s):  
Shrabanee Giri
Keyword(s):  
Reinforced Concrete ◽  
Marine Environment ◽  
Concrete Structure ◽  
Corrosion Test ◽  
Reinforced Concrete Structure ◽  
Half Cell ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Accelerated Corrosion Test ◽  
Potential Test

Corrosion of reinforcement in concrete affects the strength and durability of reinforced concrete structure. Monitoring and maintenance of concrete structure throughout the service life prevent the ingress of corrosion at the initial stage. Half-cell potential meter was developed and fabricated to monitor the corrosion potential of reinforcement in a M25 grade concrete. Half-cell potential test and accelerated corrosion test has been carried out in marine environment of 3.5% of NaCl solution. The potential behaviour of specimen subjected to accelerated corrosion is studied throughout the test period. The results were obtained in terms of current flow behaviour and weight loss. Obtained results has been analyzed graphically and a comparative analysis has been carried out to know the rate of corrosion occurred in the specimen by accelerated corrosion test and half-cell potential test. Obtained results clearly indicates that the potential behaviour value increases with increase in time from 160 mV on day 1 to 949 mV on day 5. In the other way the compressive strength value for corroded specimen is lesser than the controlled specimen subjected to accelerated corrosion.

Chloride Resistance of Concrete with Marine Blended Cement Using Corrosion Resistant Mineral Admixture

2013 ◽  
Vol 831 ◽  
pp. 23-26 ◽  
Author(s):  
Jun Yong Bae ◽  
Kyung Joon Shin ◽  
Jung Hwan Hyun ◽  
Young Il Jang ◽  
Yun Yong Kim
Keyword(s):  
Blended Cement ◽  
Steel Corrosion ◽  
Mineral Admixture ◽  
Reinforcement Corrosion ◽  
Half Cell ◽  
Cell Potential ◽  
Accelerated Corrosion ◽  
Corrosion Resistant ◽  
Chloride Resistance ◽  
Accelerated Corrosion Test

In this study, the chloride resistant properties of concrete with MBC (marine blended cement) were evaluated by an accelerated corrosion test of reinforced concrete. The half-cell potential measurements indicated that the chloride resistance of MBC concrete is approximately 32% larger than that of TBC (ternary blended cement) concrete. As for the reinforcement corrosion area, while the TBC specimens exhibited 5.32-6.11% corrosion at the final 40th cycle, the MBC specimens did not show any sign of steel corrosion. The chloride penetration depth of the MBC specimens was approximately 41-79% smaller than that of the MBC specimens.

Steel Corrosion and Control in Concrete Made with Seawater

2020 ◽  
Vol 10 (1) ◽  
pp. 58-67
Author(s):  
Arpit Goyal ◽  
S.R. Karade
Keyword(s):  
Compressive Strength ◽  
Electrical Resistivity ◽  
Corrosion Resistance ◽  
Electrochemical Impedance Spectroscopy ◽  
Fly Ash ◽  
Impedance Spectroscopy ◽  
Potable Water ◽  
Electrochemical Impedance ◽  
Half Cell ◽  
Cell Potential

Background: Water scarcity is amongst the biggest problems the world is facing in the 21st century. To reduce the consumption of Potable Water (PW) in construction industries and to make concrete construction more sustainable, its replacement with Seawater (SW) has been explored. Technical literature on this subject is not widely available. Such investigations are necessary for determining suitable remedial measures for the effective utilization of seawater for making sustainable concrete. Objective: In the present study, use of Seawater (SW) has been explored as both mixing and curing water in concrete. To counter the adverse effects of seawater on strength and corrosion resistance, use of Fly Ash (FA) and Red Mud (RM) as cement replacements in the seawater concrete had been investigated. Methods: The possibility of the use of seawater in making concrete has been explored by literature and experimental investigations. The obtained results are discussed in light of the information available in the literature. Various tests were performed such as compressive strength, Half-cell potential, electrochemical impedance spectroscopy and microstructural analysis using SEM and XRD. Result: Results showed higher compressive strength and improved corrosion resistance for Seawater Concrete (SWC) with FA & RM as compared to Potable Water Concrete (PWC) specimens. SWC specimens without supplementary cementitious materials show lower electrical resistivity and potential more negative than -450 mV indicating severe corrosion. 30% FA and 5% RM is identified as the optimum combination for the most favorable response in terms of mechanical strength and electrical resistivity of seawater concrete. After 90 days, the compressive strength of 35.77 MPa was achieved. Conclusion: Combination of both FA and RM in SWC reduces chloride migration and increases chloride binding by the formation of Friedel’s salt. Half-cell potential (HCP) and Electrochemical Impedance Spectroscopy (EIS) results confirmed a reduction in corrosion rate in SWC specimens with fly ash and red mud.

A Discuss on Basing Half-Cell Potential Method for Estimating Steel Corrosion Rate in Concrete

2012 ◽  
Vol 166-169 ◽  
pp. 1926-1930 ◽  
Author(s):  
Xiao E Zhu ◽  
Mu Xiang Dai
Keyword(s):  
Corrosion Rate ◽  
Linear Polarization ◽  
Steel Corrosion ◽  
Corrosion Current ◽  
Potential Method ◽  
Regression Equation ◽  
Half Cell ◽  
Exponential Relationship ◽  
Cell Potential ◽  
Polarization Resistance Method

Basing half-cell potential method estimating steel corrosion rate in concrete was studied in this paper. The exponential relationship between the corrosion current and the corrosion potential was regressed by the data collected from the linear polarization method experiment. Potential collected by the half-cell potential method and linear polarization resistance method in the experiment were close, it is reasonable to using regression equation. Regression equation was applied to analysis steel corrosion rate in a concrete structure column.

scholarly journals The Effect of Incorporating Industrials Wastewater on Durability and Long-Term Strength of Concrete

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4088
Author(s):  
Ehsan Nasseralshariati ◽  
Danial Mohammadzadeh ◽  
Nader Karballaeezadeh ◽  
Amir Mosavi ◽  
Uwe Reuter ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Industrial Wastewater ◽  
Construction Materials ◽  
Negative Effects ◽  
Half Cell ◽  
Cell Potential ◽  
Pore Connectivity ◽  
Air Voids ◽  
Concrete Production

Concrete, as one of the essential construction materials, is responsible for a vast amount of emissions. Using recycled materials and gray water can considerably contribute to the sustainability aspect of concrete production. Thus, finding a proper replacement for fresh water in the production of concrete is significant. The usage of industrial wastewater instead of water in concrete is considered in this paper. In this study, 450 concrete samples are produced with different amounts of wastewater. The mechanical parameters, such as slump, compressive strength, water absorption, tensile strength, electrical resistivity, rapid freezing, half-cell potential and appearance, are investigated, and a specific concentration and impurities of wastewater that cause a 10% compressive strength reduction were found. The results showed that the usage of industrial wastewater does not significantly change the main characteristics of concrete. Although increasing the concentration of wastewater can decrease the durability and strength features of concrete nonlinearly, the negative effects on durability tests are more conspicuous, as utilizing concentrated wastewaters disrupt the formation of appropriate air voids, pore connectivity and pore-size distribution in the concrete.

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