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Maintenance of reinforced concrete is a major concern around the world. In particular, special attention is now given to chloride induced corrosion, which is considered as one of the most serious causes of concrete deterioration. Since corrosion is an electrochemical process, the influence of temperature on the deterioration of reinforced concrete should be considered. From these backgrounds, the objective of this study is to investigate the influence of temperature on the deterioration process of chloride induced corrosion in reinforced concrete. The results show that the rates of diffusion of substances and corrosion of steel bars rise with increases in temperature and these phenomena are explained by the Arrhenius theory using the concept of activation energy.

This paper presents the results of laboratory and field investigations on the influence of bleeding on minute properties and steel corrosion in concrete. Test methods such as minute compressive strength test, minute tensile strength test and minute diffusion test were performed in the laboratory to assess the effect of bleeding on minute properties of concrete. In addition, electrochemical investigations were conducted both in the laboratory and in the field to determine the influence of bleeding on the rate of steel corrosion in concrete. The various test results indicate a strong agreement between the laboratory experiment and the field investigations. The upper layer of concrete affected by bleeding exhibited weaker strength, higher permeability, lower concrete resistance, and higher oxygen permeability. Consequently, a higher macrocell corrosion rate than the microcell corrosion rate prevailed in both the vertical and horizontal steel bar and the corrosion rate was enhanced at elevated temperatures o C).

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The assessment of the seismic performance of RC frame structures after one or more major seismic events is of paramount importance from the point of view of public safety. Numerical simulations by means of FEM proved to be efficient tools in assessing the seismic performance of civil engineering structures. They offer the advantage of varying several parameters in order to obtain the safety margin against structural collapse without the need of expensive experimental tests. The paper proposes a method for assessing the seismic performance of a RC frame structure by means of non-linear time-history analysis (THA). The use of numerical simulations is, in this particular case, the only solution of obtaining the safety margin to seismic actions of an existing building.