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Article
Publication date: 28 December 2020

Charis Apostolopoulos, Argyro Drakakaki, Alexandros Katsaounis, Maria Bardi and Konstantinos Faidon Koulouris

In the present study, an effort has been made to estimate the effect of significant parameters on the vulnerability of steel reinforcement to corrosion, using both…

Abstract

Purpose

In the present study, an effort has been made to estimate the effect of significant parameters on the vulnerability of steel reinforcement to corrosion, using both impressed current density technique and Tafel extrapolation method.

Design/methodology/approach

Five sets of tests were performed. Corrosion vulnerability of various diameters, temperature and pH effect on the corrosion process, potential corrosion tendency after a precorrosion period and declination from the theoretical damage prediction model are some of the parameters examined

Findings

The results of the tests provide useful information on the main parameters, determining the quality of the corrosion damage.

Originality/value

The originality of the present study is the fact that an effort has been made to estimate the effect of significant parameters on the vulnerability of steel reinforcement to corrosion, using both impressed current density technique and Tafel extrapolation method. Interesting conclusions emerged.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 23 July 2019

Argyro Drakakaki, Alkiviadis Apostolopoulos and Charis Apostolopoulos

The safety of reinforced concrete structures is generally related to the expected service life of their individual materials. Corrosion damage manifesting on steel…

Abstract

Purpose

The safety of reinforced concrete structures is generally related to the expected service life of their individual materials. Corrosion damage manifesting on steel reinforcement is usually underestimated, although it greatly affects both load bearing capacity and plastic deformation limits of steel reinforcement. Corrosion damage degree has a great impact on the life expectancy of structures. This paper aims to discuss these issues.

Design/methodology/approach

In the present study, an effort has been made to examine and present critical parameters, which are significantly responsible for the differentiation of the corrosion damage level, as far as mass loss is concerned. Consequently, the size effect of the exposed – to the aggressive conditions – area of the specimen, as well as the volume of the protected (against corrosion) area, was examined in detail.

Findings

Differential aeration greatly affects the results of corrosion on the material, given that under both high and low oxygen concentration corrosion process is still ongoing.

Originality/value

Findings proceeded are worth mentioning, as they may contribute to a more pertinent evaluation of the corrosion damage (as far as mass loss is concerned), restricting the risk of erroneous predictions concerning the mechanical behavior of steel reinforcement.

Details

International Journal of Structural Integrity, vol. 11 no. 5
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 29 September 2020

Barbara Charalambidi, Panagiotis Markou, Argyro Drakakaki and Konstantinos-Alketas Oungrinis

This study aims to discuss the causes of short-lived structuring of contemporary buildings. The life expectancy of structures may be theoretically predefined during the…

Abstract

Purpose

This study aims to discuss the causes of short-lived structuring of contemporary buildings. The life expectancy of structures may be theoretically predefined during the state of the design. This time period, known as the service life of structures, is determined by the load or the deformation level at which irreversible failures of the bearing structure may occur. On the other hand, planned obsolescence and perceived obsolescence, observed in the western world since the first half of 20th century, are currently setting an economic reality and are part of an expanded framework that, apart from architectural structures, extends to all design fields. The effects of short-lived structuring on environmental and energy terms are presented and theoretical and experimental recommendations from the literature are cited, as well as recommendations that have already been successfully applied in some countries.

Design/methodology/approach

This study aims to discuss the issues associated with short-lived structuring, durability and obsolescence of contemporary structures. For this purpose, theoretical and experimental recommendations from the literature are cited, via an extensive state of the art research.

Findings

Short-lived structuring has been a field of research during recent years. Terms such as durability are being introduced into Design Codes, while trends like perceived obsolescence and environmental impact raise issues for research. Moreover, the results of short-lived structuring are becoming more and more apparent, indicating an unsustainable reality. Issues like maintenance of structures, sustainability in design, corrosion effects, repair techniques and building waste management are an important field of research among the engineering community. In this study, the parameters affecting the lifespan of contemporary structures have been discussed.

Originality/value

The effects of short-lived structuring on environmental and energy terms are presented and theoretical and experimental recommendations from the literature are cited. The parameters studied herein concern material properties and design approach but also environmental and energy-related ones.

Details

International Journal of Structural Integrity, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 2 October 2017

Argyro Drakakaki, Charis Apostolopoulos, Alexandros Katsaounis and Hasa Bjorn

Corrosive agent constitutes a major problem for constructions located in coastal areas, since it keeps affecting their durability. This phenomenon, in synergy with…

Abstract

Purpose

Corrosive agent constitutes a major problem for constructions located in coastal areas, since it keeps affecting their durability. This phenomenon, in synergy with moisture and high temperatures, leads to premature deterioration of the structures. Under these conditions, the need for management of the problem of resistance of steel against corrosion is an issue of paramount importance and a challenge to the structural integrity and reliability. The paper aims to discuss these issues.

Design/methodology/approach

The need for management of the problem of resistance of steel against corrosion is an issue of paramount importance and a challenge to the structural integrity and reliability. In the present study, an effort was made to increase the corrosion resistance of the high strength and ductility dual-phase steel B500c category, with the use of different shot blasting processes, without any interference in the chemical composition or in the production mode. In particular, shot blasting treatment was used for both cleaning and creating compressive stresses on the surface of steel bars, according to the pertinent protocols. The modified samples were studied via both conventional characterization methods and electrochemical techniques.

Findings

Through the whole surface treatment process of B500c steel, a positive impact came about not only the corrosion resistance, but also the mechanical performance.

Originality/value

Shot blasting process aims to increase the corrosion resistance of high ductility dual-phase steel (B500c), without any interference in the chemical composition or in the production mode.

Details

International Journal of Structural Integrity, vol. 8 no. 5
Type: Research Article
ISSN: 1757-9864

Keywords

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Article
Publication date: 4 February 2019

Charis Apostolopoulos, Argyro Drakakaki and Maria Basdeki

As it is widely known, corrosion is a major deterioration factor for structures which are located on coastal areas. Corrosion has a great impact on both the durability and…

Abstract

Purpose

As it is widely known, corrosion is a major deterioration factor for structures which are located on coastal areas. Corrosion has a great impact on both the durability and seismic performance of reinforced concrete structures. In the present study, two identical reinforced concrete columns were constructed and mechanical tests were organized to simulate seismic conditions. Prior to the initiation of the mechanical tests, the base of one of the two columns was exposed to predetermined accelerated electrochemical corrosion (at a height of 60 cm from the base). After the completion of the experimental loading procedure, the hysteresis curves – for unilateral and bilateral loadings – of the two samples were presented and analyzed (in terms of strength, displacement and dissipated energy). The paper aims to discuss this issue.

Design/methodology/approach

In the present study, two identical reinforced concrete columns were constructed and mechanical tests were organized to simulate seismic conditions. The tests were executed under the combination of a constant vertical force with horizontal, gradually increasing, cyclic loads. The implemented displacements, of the free end of the column, ranged from 0.2 to 5 percent. Prior to the initiation of the mechanical tests, the base of one of the two columns was exposed to predetermined accelerated electrochemical corrosion (at a height of 60 cm from the base). After the completion of the experimental loading procedure, the hysteresis curves of the two samples were presented and analyzed (in terms of strength, displacement and dissipated energy).

Findings

Analyzing the results, for both unilateral and bilateral loadings, a significant reduction of the seismic performance of the corroded column was highlighted. The corrosion damage imposed on the reference column resulted in the dramatic decrease of its energy reserves, even though an increase in ductility was recorded. Furthermore, more attention was paid to the consequences of the uneven corrosion damage, recorded on the steel bars examined, on ductility, hysteretic behavior and damping ratio.

Originality/value

In the present paper, the influence of the corrosion effects on the cyclic response of structural elements was presented and analyzed. The simulation of the seismic conditions was achieved by imposing, at the same time, a constant vertical force and horizontal, gradually increasing, cyclic loads. Finally, an evaluation of the performance of a column, under both unilateral and bilateral loadings, took place before and after corrosion.

Details

International Journal of Structural Integrity, vol. 10 no. 1
Type: Research Article
ISSN: 1757-9864

Keywords

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