Documents disponibles écrits par cet auteur

An embedded multi-parameter corrosion sensor for reinforced concrete structures / H. Yu in Materials and corrosion, Vol. 63 N° 11 (Novembre 2012) 

Public ISBD [article]  in Materials and corrosion > Vol. 63 N° 11 (Novembre 2012) . - pp. 1011–1016 Titre : An embedded multi-parameter corrosion sensor for reinforced concrete structures Type de document : texte imprimé Auteurs : H. Yu, Auteur ; L. Caseres, Auteur Année de publication : 2014 Article en page(s) : pp. 1011–1016 Note générale : Génie mécanique Langues : Anglais (eng) Mots-clés : Chloride  threshold  concentration;  corrosion  sensor;  linear  polarization  resistance  (LPR);  reinforcing  steel  bar  (rebar);  simulated  pore  solutions  (SPSs) Résumé : A prototype of an embedded corrosion sensor has been developed for assessing the corrosion status of reinforcing steel bar (rebar) in concrete. The integrated sensor unit includes an Ag/AgCl probe, a metallic oxide probe, a multi-electrode array sensor (MAS), and a four-pin (Wenner) array stainless steel electrode for chloride content, pH, microcell corrosion current, and localized concrete resistivity measurements, respectively. A stable solid probe was used as the reference probe in this unit to express the potentiometric measurement of chloride content and pH probes. In this study, the chloride and pH probes were calibrated in simulated pore solutions (SPSs) regarding temperature and pH fluctuations. The corrosion current results of the MAS probe in SPSs matched very well with those obtained by the linear polarization resistance technique, which was conducted on companion carbon steel specimens. A sensor prototype was embedded into a paste cylinder for long-term performance evaluation. Up-to-date results show that the sensor probes exhibit excellent sensitivity and reliability through 1 year of monitoring. Continuous monitoring in the laboratory for extended periods is underway. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106113/abstract [article] An embedded multi-parameter corrosion sensor for reinforced concrete structures [texte imprimé] / H. Yu, Auteur ; L. Caseres, Auteur . - 2014 . - pp. 1011–1016. Génie mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 63 N° 11 (Novembre 2012) . - pp. 1011–1016 Mots-clés : Chloride  threshold  concentration;  corrosion  sensor;  linear  polarization  resistance  (LPR);  reinforcing  steel  bar  (rebar);  simulated  pore  solutions  (SPSs) Résumé : A prototype of an embedded corrosion sensor has been developed for assessing the corrosion status of reinforcing steel bar (rebar) in concrete. The integrated sensor unit includes an Ag/AgCl probe, a metallic oxide probe, a multi-electrode array sensor (MAS), and a four-pin (Wenner) array stainless steel electrode for chloride content, pH, microcell corrosion current, and localized concrete resistivity measurements, respectively. A stable solid probe was used as the reference probe in this unit to express the potentiometric measurement of chloride content and pH probes. In this study, the chloride and pH probes were calibrated in simulated pore solutions (SPSs) regarding temperature and pH fluctuations. The corrosion current results of the MAS probe in SPSs matched very well with those obtained by the linear polarization resistance technique, which was conducted on companion carbon steel specimens. A sensor prototype was embedded into a paste cylinder for long-term performance evaluation. Up-to-date results show that the sensor probes exhibit excellent sensitivity and reliability through 1 year of monitoring. Continuous monitoring in the laboratory for extended periods is underway. En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.201106113/abstract

Correction of chloride threshold concentration and time-to-corrosion due to reinforcement presence / H. Yu in Materials and corrosion, Vol. 62 N° 5 (Mai 2011) 

Public ISBD [article]  in Materials and corrosion > Vol. 62 N° 5 (Mai 2011) . - pp. 423–430 Titre : Correction of chloride threshold concentration and time-to-corrosion due to reinforcement presence Type de document : texte imprimé Auteurs : H. Yu, Auteur ; W. Hartt, Auteur Année de publication : 2011 Article en page(s) : pp. 423–430 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Chloride  threshold  concentration  Diffusion  coefficient  Reinforcement  Time-to-corrosion Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Reinforcement presence affecting corrosion threshold concentration, Ct, determination and time-to-corrosion, Ti, has been investigated. Elevated Ct and decreased Ti due to reinforcement physical obstruction on the path of chloride ingression into concrete has been examined with finite element modeling. Results indicated that reinforcement with larger size, better corrosion resistance, less cover thickness, or a more flat leading edge causes more pronounced Ti reduction. Experimental results exposed aggregate content discrepancy within reinforced bar vicinity zone. According to this finding, a multi-shell chloride diffusion model, in which specific chloride ion diffusivity in each shell surrounding bar presents, is proposed. The Ct results of proposed model are discussed along with those acquired from traditional one-dimensional model, in which chloride diffusion follows Fick's second law without considering reinforcement presence, and two-dimensional model with the effect of reinforcement physical obstruction regarded. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905516/abstract [article] Correction of chloride threshold concentration and time-to-corrosion due to reinforcement presence [texte imprimé] / H. Yu, Auteur ; W. Hartt, Auteur . - 2011 . - pp. 423–430. Génie Mécanique Langues : Anglais (eng) in Materials and corrosion > Vol. 62 N° 5 (Mai 2011) . - pp. 423–430 Mots-clés : Chloride  threshold  concentration  Diffusion  coefficient  Reinforcement  Time-to-corrosion Index. décimale : 620.1 Essais des matériaux. Défauts des matériaux. Protection des matériaux Résumé : Reinforcement presence affecting corrosion threshold concentration, Ct, determination and time-to-corrosion, Ti, has been investigated. Elevated Ct and decreased Ti due to reinforcement physical obstruction on the path of chloride ingression into concrete has been examined with finite element modeling. Results indicated that reinforcement with larger size, better corrosion resistance, less cover thickness, or a more flat leading edge causes more pronounced Ti reduction. Experimental results exposed aggregate content discrepancy within reinforced bar vicinity zone. According to this finding, a multi-shell chloride diffusion model, in which specific chloride ion diffusivity in each shell surrounding bar presents, is proposed. The Ct results of proposed model are discussed along with those acquired from traditional one-dimensional model, in which chloride diffusion follows Fick's second law without considering reinforcement presence, and two-dimensional model with the effect of reinforcement physical obstruction regarded. DEWEY : 620.1 ISSN : 0947-5117 En ligne : http://onlinelibrary.wiley.com/doi/10.1002/maco.200905516/abstract