Progress on Design and Residual Life Calculation with Regard to Rebar Corrosion of Reinforced Concrete

2009 ◽  
pp. 23-23-18 ◽  
Author(s):  
C Andrade ◽  
C Alonso
Keyword(s):  
Reinforced Concrete ◽  
Residual Life ◽  
Rebar Corrosion

scholarly journals Degradation Monitoring in Reinforced Concrete with 3D Localization of Rebar Corrosion and Related Concrete Cracking

2021 ◽  
Vol 11 (15) ◽  
pp. 6772
Author(s):  
Charlotte Van Steen ◽  
Els Verstrynge
Keyword(s):  
Reinforced Concrete ◽  
Degradation Mechanism ◽  
Heterogeneous Material ◽  
Corrosion Damage ◽  
Corrosion Process ◽  
Internal Damage ◽  
Rc Structures ◽  
Degradation Monitoring ◽  
Rebar Corrosion ◽  
Width Measurements

Corrosion of the reinforcement is a major degradation mechanism affecting durability and safety of reinforced concrete (RC) structures. As the corrosion process starts internally, it can take years before visual damage can be noticed on the surface, resulting in an overall degraded condition and leading to large financial costs for maintenance and repair. The acoustic emission (AE) technique enables the continuous monitoring of the progress of internal cracking in a non-invasive way. However, as RC is a heterogeneous material, reliable damage detection and localization remains challenging. This paper presents extensive experimental research aiming at localizing internal damage in RC during the corrosion process. Results of corrosion damage monitoring with AE are presented and validated on three sample scales: small mortar samples (scale 1), RC prisms (scale 2), and RC beams (scale 3). For each scale, the corrosion process was accelerated by imposing a direct current. It is found that the AE technique can detect damage earlier than visual inspection. However, dedicated filtering is necessary to reliably localize AE events. Therefore, AE signals were filtered by a newly developed post-processing protocol which significantly improves the localization results. On the smallest scale, results were confirmed with 3D micro-CT imaging, whereas on scales 2 and 3, results were compared with surface crack width measurements and resulting rebar corrosion levels.

Expected residual service life of reinforced concrete structures from current strength considerations

2019 ◽  
Vol 22 (7) ◽  
pp. 1631-1643
Author(s):  
Sushil Kumar Dhawan ◽  
Abhinav Bindal ◽  
Suresh Bhalla ◽  
Bishwajit Bhattacharjee
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Residual Life ◽  
Concrete Structures ◽  
Present Condition ◽  
Material Strength ◽  
Reinforced Concrete Structures ◽  
Residual Service Life ◽  
Remaining Service Life ◽  
Residual Service

Concrete is primarily used in the form of reinforced concrete for construction of buildings, bridges and other important structures. Due to normal usage and environmental effects, the structure would gradually deteriorate. The actual residual life needs to be worked at a given time vis-à-vis the design life of the structure, commensurate with the fulfilment of essential requirements of structural integrity and safety and from strength as well as serviceability considerations. Requirements for residual life assessment would depend upon the current parameters, such as the residual cross-sectional area of concrete as well as steel, Young’s modulus of elasticity and the in situ material strength of the constituent materials, namely, concrete and steel. This article aims to develop a rigorous methodology for expected remaining service life of a reinforced concrete structure from wind/seismic considerations, based on the present condition of the structure encompassing the residual material strength and the residual reinforcement/sectional areas. The methodology development section is followed by an illustrative example and a parametric study involving a 10-storeyed reinforced concrete building frame under wind and earthquake loads. Influences of various parameters such as concrete strength and residual rebar area on the expected remaining service life are studied in detail. The proposed methodology provides a simple but rational estimation of the residual service life for reinforced concrete structures.

Research on Corrosion of Reinforced Concrete Structures by Chloridion in Port Engineering Construction

2011 ◽  
Vol 90-93 ◽  
pp. 2483-2486 ◽  
Author(s):  
Yan Ying Dong ◽  
Li Shan Zhang ◽  
Ming Zhang ◽  
Tian Zhi Zhu
Keyword(s):  
Reinforced Concrete ◽  
Structural Damage ◽  
Raw Materials ◽  
Concrete Structures ◽  
Raw Material ◽  
Reinforced Concrete Structures ◽  
Engineering Construction ◽  
Rebar Corrosion ◽  
The Right ◽  
Port Engineering

In port engineering construction, the source of chloridion is concrete raw materials, admixtures and the penetration of seawater. Chloridion makes rebar corrosion, and makes the expansion and crack of reinforcement concrete, leading to concrete structural damage. By selecting the right concrete raw material, appropriate admixtures and to ensure concrete construction quality, in order to effectively avoid chloridion to the damage of reinforced concrete structures in construction.

Prediction of residual flexural strength of corroded reinforced concrete beams

2017 ◽  
Vol 64 (1) ◽  
pp. 69-74 ◽  
Author(s):  
Shamsad Ahmad
Keyword(s):  
Reinforced Concrete ◽  
Flexural Strength ◽  
Current Density ◽  
Empirical Model ◽  
Corrosion Current Density ◽  
Concrete Beams ◽  
Corrosion Current ◽  
Reinforced Concrete Beams ◽  
Content Type ◽  
Rebar Corrosion

Purpose This study aims to make an effort to develop a model to predict the residual flexural strength of reinforced concrete beams subjected to reinforcement corrosion. Design/methodology/approach For generating the required data to develop the model, a set of experimental variables was considered that included corrosion current density, corrosion duration, rebar diameter and thickness of concrete cover. A total of 28 sets of reinforced concrete beams of size 150 × 150 × 1,100 mm were cast, of which 4 sets of un-corroded beams were tested in four-point bend test as control beams and the remaining 24 sets of beams were subjected to accelerated rebar corrosion inducing different levels of corrosion current densities for different durations. Corroded beams were also tested in flexure, and test results of un-corroded and corroded beams were utilized to obtain an empirical model for estimating the residual flexural strength of beams for given corrosion current density, corrosion duration and diameter of the rebars. Findings Comparison of the residual flexural strengths measured experimentally for a set of corroded beams, reported in literature, with that predicted using the model proposed in this study indicates that the proposed model has a reasonably good accuracy. Originality/value The empirical model obtained under this work can be used as a simple tool to predict residual flexural strength of corroded beams using the input data that include rebar corrosion rate, corrosion duration after initiation and diameter of rebars.

Status of Site Test Methods of Organosilicon Hydrophobic Impregnants for Protecting Reinforced Concrete

2014 ◽  
Vol 638-640 ◽  
pp. 1676-1682
Author(s):  
Zong Yang Yuan ◽  
Hong Yao Sun ◽  
Zheng Yang ◽  
Ming Xia Shen ◽  
Guo Liang Shan
Keyword(s):  
Reinforced Concrete ◽  
Water Absorption ◽  
Test Methods ◽  
Chloride Penetration ◽  
Water Repellent ◽  
Repellent Property ◽  
Advantages And Disadvantages ◽  
The Status ◽  
Rebar Corrosion ◽  
Site Test

The organosilicon hydrophobic impregnants is applied on concrete to prevent rebar corrosion with its water repellent property which can prevent the intrusion of chloride and other harmful media. On-site the parameters of organosilicon hydrophobic impregnants of controlling quality consist of resistance to chloride penetration, water absorption of concrete and impregnating depth of organosilicon hydrophobic impregnants. The status of test methods of these parameters is summarized and their advantages and disadvantages are briefly reviewed. Finally some ideas are presented about shortcomings of test methods.

Study on Flexural Resistance of Corroded Reinforced Concrete Walls

2013 ◽  
Vol 742 ◽  
pp. 76-79
Author(s):  
Shun Bo Zhao ◽  
Fu Lai Qu ◽  
Shi Min Zhang ◽  
Chang Ming Li ◽  
Peng Bing Hou
Keyword(s):  
Reinforced Concrete ◽  
Yellow River ◽  
Concrete Strength ◽  
Eccentric Load ◽  
Concrete Walls ◽  
Normal Section ◽  
Reinforced Concrete Walls ◽  
Flexural Failure ◽  
Rebar Corrosion ◽  
Flexural Resistance

On the requirement of evaluating the bearing capacity of corroded reinforced concrete lock-walls servicing on the Yellow River, the experimental study was conducted to investigate the loading behaviours of normal section of lock-walls, which considered the changes of concrete strength and corrosion level of rebar. The rebar corrosion was accelerated by the mixing of sodium chloride (NaCl) into concrete and the electrolyte corrosion technique in condition of dry-wet curing. The vertical eccentric load was applied on the top of the wall. The results show that some horizontal cracks firstly appeared on the surface of walls during the corrosion period and became wider under the vertical load on the wall. The typical ultimate state was flexural failure. The effects of concrete strength and rebar corrosion level on the resistance of normal section are analyzed based on the test data.

scholarly journals Relación entre la velocidad de corrosión de la armadura y el ancho de fisuras en vigas de concreto armado expuestas a ambientes que simulan el medio marino

2016 ◽  
Vol 6 (3) ◽  
pp. 272-283
Author(s):  
Y. Hernández ◽  
O. Troconis de Rincón ◽  
A. Torres ◽  
S. Delgado ◽  
J. Rodríguez ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Corrosion Rate ◽  
Crack Width ◽  
Concrete Beams ◽  
Propagation Rate ◽  
Concrete Cover ◽  
Corrosion Process ◽  
Reinforced Concrete Beams ◽  
Electrochemical Tests ◽  
Rebar Corrosion

Relación entre la velocidad de corrosión de la armadura y el ancho de fisuras en vigas de concreto armado expuestas a ambientes que simulan el medio marino  RESUMENEsta investigación presenta una relación empírica entre la velocidad de corrosión de la armadura y la velocidad de ensanchamiento de fisuras por corrosión del recubrimiento de concreto en vigas, con o sin aplicación de carga. Se evaluaron vigas de concreto armado, expuestas a un proceso de corrosión natural mediante el rociado con solución salina al 3,5 %p/p de NaCl, para acelerar el proceso corrosivo de la armadura, mediante ensayos electroquímicos. El ancho de fisuras se evaluó mensualmente para estimar la relación existente entre éste y la pérdida de sección de la armadura. Los resultados demuestran que existe una relación directa entre la propagación del ancho de fisuras y la velocidad de corrosión, observando fisuras de mayor ancho en vigas cargadas.Palabras clave: corrosion; concreto armado; vigas cargadas; ancho de fisuras. Reinforcement corrosion rate and crack width relationship in concrete beams exposed to simulated marine environment ABSTRACTThis investigation presents an empirical correlation between the rebar corrosion rate and the corrosion-induced crack width propagation rate produced on beam's concrete cover, with or without load application to these beams. Reinforced concrete beams were evaluated, exposed to a natural corrosion process by spraying with 3.5 %w/w NaCl solution, to accelerate the rebar corrosion process, was performed with electrochemical tests. The beams corrosion-cracking evaluation was performed once every month, to determine the relation between crack width and the rebar corrosion loss. The results showed a direct relation between crack width propagation and rebar corrosion rate, showing wider cracks in the loaded beams.Keywords: corrosion; reinforced concrete; loaded beams; crack widths. Relação entre a velocidade de corrosão da armadura e a largura das fissuras em vigas de concreto armado expostas a ambientes que simulam o ambiente marinho RESUMOEsta pesquisa apresenta uma relação empírica entre a taxa de corrosão da armadura e a abertura de fissuras por efeito da corrosão da armadura em vigas de concreto, com ou sem aplicação de carga. Foram avaliadas vigas de concreto armado, expostas a um processo de corrosão natural por pulverização com solução salina a concentração de 3,5% de NaCl, para acelerar o processo de corrosão da armadura, mediante ensaios eletroquímicos. A abertura das fissuras foi avaliada mensalmente para estimar a relação entre ela e a perda de seção da armadura. Os resultados mostram que existe uma relação direta entre a propagação da abertura da fissura e a taxa de corrosão, observando a ocorrência de fissuras de maior abertura nas vigas sob carga.Palavras-chave: corrosão; vigas de concreto armado sob carga; abertura de fissuras. 

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