The deterioration of reinforced concrete due to the corrosion of the reinforcing bars may be expressed as the sum of three time events: time to initiation of corrosion, time to first spalling, and time to failure. Three corrosion processes have to be characterised to determine the corrosion state of the concrete within the three events. The three processes are the rate of chloride diffusion and present level of chloride contamination, rate of corrosion, and rate of maintenance activities from first spalling to failure. Thus, measuring the chloride content of concrete as a function of depth is critical to determining the chloride contamination state and the rate of chloride diffusion into concrete. The present standard methods are too arduous, time-consuming, and costly for use in the field and for measuring the chloride content of the relatively large number of samples needed to characterise the chloride contamination level of concrete bridges. The laboratory work in the development of a field-worthy method of measuring the chloride content of reinforced concrete structures was addressed in this study. (Author/publisher)
Abstract