Konstantinos F. Koulouris and Charis Apostolopoulos
As it is widely known, corrosion constitutes a major deterioration factor for reinforced concrete (RC) structures which are located on coastal areas. This phenomenon combined with…
Abstract
Purpose
As it is widely known, corrosion constitutes a major deterioration factor for reinforced concrete (RC) structures which are located on coastal areas. This phenomenon combined with repeated loads, as earthquake events, negatively affects their service life. Moreover, microstructure of steel reinforcing bars has significant impact either on their corrosion resistance or on their fatigue life.
Design/methodology/approach
In the present manuscript an effort has been made to investigate the effect of corrosive factor on fatigue response for two types of steel reinforcement; Tempcore steel reinforcing bars and a new generation dual phase (DP) steel reinforcement.
Findings
The findings of this experimental study showed that DP steel reinforcement led to better results regarding its capacity to bear repeated loads to satisfactory degree after corrosion, although this type of steel has less stringent mechanical properties.
Originality/value
Additionally, a fatigue damage material indicator is proposed as a parameter that could rank material quality and its suitability for a certain application. The results of this investigation showed that the fatigue damage indicator can be used as an appropriate index in order to evaluate the overall performance of materials, in terms of strength and ductility capacity.
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Charis Apostolopoulos, George Konstantopoulos and Konstantinos Koulouris
Structures in seismic areas, during their service lifetime, are subjected to numerous seismic loads that certainly affect their structural integrity. The degradation of these…
Abstract
Purpose
Structures in seismic areas, during their service lifetime, are subjected to numerous seismic loads that certainly affect their structural integrity. The degradation of these structures, to a great extent, depends on the scale of seismic events, the steel mechanical performance on reversal loads and its resistance to corrosion phenomena. The paper aims to discuss these issues.
Design/methodology/approach
Based on the experimental results of seismic steel behavior S400 (BSt III), which was widely used in the past years, a prediction study of seismic steel behavior was conducted in the current study. This prediction on behavior of both reference and corroded steel was succeeded through a simulation of experimental low cycle fatigue conditions (LCF – strain controlled).
Findings
At the same time, the present study analyses fatigue factors (ef, a, fSR, ed, ep, R, b) that define their inelastic relation between tension – strain and a prediction model on behavior of both reference and corroded steel rebar, in seismic loads conditions (LCF), is proposed.
Originality/value
Moreover, this study dealt with the synergy of corrosion factor and the existence of superficial ribs (ribbed and smoothed) in seismic behavior of steel bar S400 (BSt420). The S-N curves that are exported can be resulted in a first attempt of prediction of anti-seismic behavior on reinforced concrete structures with this the same steel class.
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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 impressed…
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.
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Dimitrios Kouis, Konstantinos Kyprianos, Foteini Efthymiou, Alexandros Koulouris and Antonia Karabela
The purpose of this article is to investigate certain aspects, problems and benefits from the migration to a shared Library Management System (LMS).
Abstract
Purpose
The purpose of this article is to investigate certain aspects, problems and benefits from the migration to a shared Library Management System (LMS).
Design/methodology/approach
A review of the literature and a quantitative survey was conducted, based on a structured questionnaire, with a response rate of 44.7%.
Findings
Among the crucial issues that should be taken seriously into consideration when transiting into a new and shared LMS, are the audit of the data quality before migration, the employees' training design and the composition of the LMS central support team. The benefits of a shared LMS are mainly effectiveness in terms of libraries' budgets and time for the employees' day-to-day work.
Originality/value
The survey presented in this article evaluates the merits of a shared LMS and contributes innovative aspects to the existing bibliography by investigating issues and problems that arose during the transition. This way, the professionals involved in similar initiatives will benefit by avoiding possible mistakes and drawbacks when implementing such a project.
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Eleftheria Papastefanaki, Christos Papathanasiou and Nikos Vafeas