... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la dis... more ... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la distance entre les fissures de flexion et de hauteur égale à celle de la poutre. ... Figure 12. Comportement global force-flèche pour la poutre 412. Pour ...
European Journal of Environmental and Civil Engineering, 2012
Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. ... more Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. Much research has been carried out to investigate the influence of cracks on rebar corrosion. In this project ring shaped mortar samples with an 8mm steel bar inside were cracked with different crack widths and then subjected to continuous wetting and drying cycles in salt
European Journal of Environmental and Civil Engineering, 2014
ABSTRACT This article introduces the results of experiments on 25-year-old reinforced concrete be... more ABSTRACT This article introduces the results of experiments on 25-year-old reinforced concrete beams under the effect of service load. Two reinforced concrete beams were stored in a chloride environment and allowed to corrode, while a non-corroded control beam was stored in the normal laboratory environment. A finite macro-element model for corroded reinforced concrete, taking account of the influence of corrosion development and the reduction of the bond between longitudinal steel reinforcement and concrete, was applied to calculate the mechanical behaviour of the beams. The comparison between the theoretical calculation and the experimental results showed that, when evaluating the mechanical behaviour of corroded reinforced concrete, besides the factors of length, width of cracks due to corrosion, and the number of cross-beam-axis cracks, it is necessary to consider transverse cracks in the cross-section of the beam due to corrosion of the transverse reinforcement.
... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la dis... more ... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la distance entre les fissures de flexion et de hauteur égale à celle de la poutre. ... Figure 12. Comportement global force-flèche pour la poutre 412. Pour ...
The structural response of post-tensioned beams with bonded wires has been studied experimentally... more The structural response of post-tensioned beams with bonded wires has been studied experimentally, and a numerical model is proposed. The tests simulated the effect of stress corrosion failure and development of anchorage of the wires on each side of the fracture. The residual structural performance for loading up to failure was also measured. The nonlinear finite element model with interface elements reproduces the different phases of prestressing wire breaking with rebonding and loading of the beam, taking into account local and global parameters. The distribution of damage caused by wire breaking has been assumed to occur in different locations and different failure modes were studied. Conclusions are drawn for the performance of deteriorating prestressed structures.
This paper presents an experimental study of the stress corrosion cracking (SCC) process on 8-mm-... more This paper presents an experimental study of the stress corrosion cracking (SCC) process on 8-mm-diameter wires which are used industrially in precast concrete prestressed by pre-tension. The service life of steel wires under accelerated SCC and the reduction of their mechanical performance are studied. A dynamic analysis to detect the damage to corroded wire due to SCC before brittle failure and the influence of internal defects on the service life of stress corroded wire are also presented. The study shows that stress corrosion cracking is characterized by an evolution to SCC from pitting corrosion attacks that result in the development of both micro-cracking and micro-voids in the steel bulk. The stress level does not influence the composition of corrosion products. It is a major factor of SCC development, leading to a considerable reduction in the ultimate strain and thus to brittle failure of the corroded wires. Local defects on the steel surface increase the SCC effect due to stress corrosion concentration. A reduction in the elastic modulus and the elastic limit, which may reach 25% and 15%, respectively, can be expected due to steel micro-cracking. No damage detection through mechanical analysis seems possible before the brittle failure occurs as the corrosion is very localized and so does not globally reduce the tension in the wires.
... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la dis... more ... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la distance entre les fissures de flexion et de hauteur égale à celle de la poutre. ... Figure 12. Comportement global force-flèche pour la poutre 412. Pour ...
European Journal of Environmental and Civil Engineering, 2012
Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. ... more Corrosion is one of the major problems that the reinforced concrete industry is facing nowadays. Much research has been carried out to investigate the influence of cracks on rebar corrosion. In this project ring shaped mortar samples with an 8mm steel bar inside were cracked with different crack widths and then subjected to continuous wetting and drying cycles in salt
European Journal of Environmental and Civil Engineering, 2014
ABSTRACT This article introduces the results of experiments on 25-year-old reinforced concrete be... more ABSTRACT This article introduces the results of experiments on 25-year-old reinforced concrete beams under the effect of service load. Two reinforced concrete beams were stored in a chloride environment and allowed to corrode, while a non-corroded control beam was stored in the normal laboratory environment. A finite macro-element model for corroded reinforced concrete, taking account of the influence of corrosion development and the reduction of the bond between longitudinal steel reinforcement and concrete, was applied to calculate the mechanical behaviour of the beams. The comparison between the theoretical calculation and the experimental results showed that, when evaluating the mechanical behaviour of corroded reinforced concrete, besides the factors of length, width of cracks due to corrosion, and the number of cross-beam-axis cracks, it is necessary to consider transverse cracks in the cross-section of the beam due to corrosion of the transverse reinforcement.
... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la dis... more ... 2006). Le modèle est basé sur la définition d'un macro-élément de largeur égale à la distance entre les fissures de flexion et de hauteur égale à celle de la poutre. ... Figure 12. Comportement global force-flèche pour la poutre 412. Pour ...
The structural response of post-tensioned beams with bonded wires has been studied experimentally... more The structural response of post-tensioned beams with bonded wires has been studied experimentally, and a numerical model is proposed. The tests simulated the effect of stress corrosion failure and development of anchorage of the wires on each side of the fracture. The residual structural performance for loading up to failure was also measured. The nonlinear finite element model with interface elements reproduces the different phases of prestressing wire breaking with rebonding and loading of the beam, taking into account local and global parameters. The distribution of damage caused by wire breaking has been assumed to occur in different locations and different failure modes were studied. Conclusions are drawn for the performance of deteriorating prestressed structures.
This paper presents an experimental study of the stress corrosion cracking (SCC) process on 8-mm-... more This paper presents an experimental study of the stress corrosion cracking (SCC) process on 8-mm-diameter wires which are used industrially in precast concrete prestressed by pre-tension. The service life of steel wires under accelerated SCC and the reduction of their mechanical performance are studied. A dynamic analysis to detect the damage to corroded wire due to SCC before brittle failure and the influence of internal defects on the service life of stress corroded wire are also presented. The study shows that stress corrosion cracking is characterized by an evolution to SCC from pitting corrosion attacks that result in the development of both micro-cracking and micro-voids in the steel bulk. The stress level does not influence the composition of corrosion products. It is a major factor of SCC development, leading to a considerable reduction in the ultimate strain and thus to brittle failure of the corroded wires. Local defects on the steel surface increase the SCC effect due to stress corrosion concentration. A reduction in the elastic modulus and the elastic limit, which may reach 25% and 15%, respectively, can be expected due to steel micro-cracking. No damage detection through mechanical analysis seems possible before the brittle failure occurs as the corrosion is very localized and so does not globally reduce the tension in the wires.
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