This paper focuses on methodological issues relevant to corrosion risk prediction models.A model was developed for the prediction of corrosion rates associated with hot-dip galvanised reinforcement bar material in con...This paper focuses on methodological issues relevant to corrosion risk prediction models.A model was developed for the prediction of corrosion rates associated with hot-dip galvanised reinforcement bar material in concrete exposed to carbonation and chlorides in outdoor environment.One-year follow-up experiments,over five years,were conducted at various carbonation depths and chloride contents.The observed dependence of corrosion rate on the depth of carbonation and chloride content is complex indicating that the interaction between the carbonation and chloride influencing the corrosion.A non-linear corrosion model was proposed with statistical analysis to model the relationship between the corrosion rate and the test parameters.The main methodological contributions are(i)the proposed modeling approach able to take into account the uncertain measurement errors including unobserved systematic and random heterogeneity over different measured specimens and correlation for the same specimen across different measuring times,which best suits the measurement data;(ii)the developed model in which an interaction parameter is introduced especially to account for the contribution and the degree of the unobserved carbonation-chloride interaction.The proposed model offers greater flexibility for the modelling of measurement data than traditional models.展开更多
Reinforced concrete structure durability has been getting a lot of attention in academic research related to building security and stability.Thus,knowledge about the condition of the structures,particularly those affe...Reinforced concrete structure durability has been getting a lot of attention in academic research related to building security and stability.Thus,knowledge about the condition of the structures,particularly those affected by issue symptoms,is a powerful tool to minimize costs and improve structural reinforcement and repair service efficiency.Steel corrosion in reinforced concrete frames is the most frequent pathological manifestation in buildings around the world,and it is closely linked to the concept of structural integrity and safety.This paper describes,explains and remarks on the services performed by a company specialized in structure pathology in determining the causes,origins and mechanisms involved in steel corrosion in reinforced concrete frames in the ground and mezzanine floors of a building located in the coastal city of Cabedelo/PB.Mechanical,physical,chemical and electrochemical tests were conducted in the structure,and the conclusion was that concrete carbonation was the mechanism behind the pathological manifestation,and the source of the issue was linked to the execution of the work.The therapy process adopted was divided into levels related to the degree and progress in the observed degradation,and a few structural repair techniques were adopted,such as traditional structure repair,chemical realkalinization,corrosion inhibition and surface protection.展开更多
基金study is financed by the Academy of Finland(Grant number 324023)Dr.Esko Sistonen provided the experimental data.
文摘This paper focuses on methodological issues relevant to corrosion risk prediction models.A model was developed for the prediction of corrosion rates associated with hot-dip galvanised reinforcement bar material in concrete exposed to carbonation and chlorides in outdoor environment.One-year follow-up experiments,over five years,were conducted at various carbonation depths and chloride contents.The observed dependence of corrosion rate on the depth of carbonation and chloride content is complex indicating that the interaction between the carbonation and chloride influencing the corrosion.A non-linear corrosion model was proposed with statistical analysis to model the relationship between the corrosion rate and the test parameters.The main methodological contributions are(i)the proposed modeling approach able to take into account the uncertain measurement errors including unobserved systematic and random heterogeneity over different measured specimens and correlation for the same specimen across different measuring times,which best suits the measurement data;(ii)the developed model in which an interaction parameter is introduced especially to account for the contribution and the degree of the unobserved carbonation-chloride interaction.The proposed model offers greater flexibility for the modelling of measurement data than traditional models.
文摘Reinforced concrete structure durability has been getting a lot of attention in academic research related to building security and stability.Thus,knowledge about the condition of the structures,particularly those affected by issue symptoms,is a powerful tool to minimize costs and improve structural reinforcement and repair service efficiency.Steel corrosion in reinforced concrete frames is the most frequent pathological manifestation in buildings around the world,and it is closely linked to the concept of structural integrity and safety.This paper describes,explains and remarks on the services performed by a company specialized in structure pathology in determining the causes,origins and mechanisms involved in steel corrosion in reinforced concrete frames in the ground and mezzanine floors of a building located in the coastal city of Cabedelo/PB.Mechanical,physical,chemical and electrochemical tests were conducted in the structure,and the conclusion was that concrete carbonation was the mechanism behind the pathological manifestation,and the source of the issue was linked to the execution of the work.The therapy process adopted was divided into levels related to the degree and progress in the observed degradation,and a few structural repair techniques were adopted,such as traditional structure repair,chemical realkalinization,corrosion inhibition and surface protection.
