Porosity influence on life time of concrete structures analysed by chloride migration testing

Author(s): I. H. Santos, C.A.C. Souza, D. V. Ribeiro
Paper category: Workshop
Book title: RILEM International workshop on performance-based specification and control of concrete durability
Editor(s): D. Bjegović, H. Beushausen, M. Serdar
ISBN: 978-2-35158-135-3
e-ISBN: 978-2-35158-136-0
Pages: 471 - 480
Total Pages: 10
Language: English

Abstract: 
In concrete structures, it is widely accepted that the presence of chloride ions is responsible for causing a located breaking in the passive layer and consequently the corrosion of reinforcing steel bars. This phenomenon is usually associated with the inadequate thickness of the concrete coatings, and especially the ease of entry of harmful agents through the concrete microstructure. In the present study, the effect of the microstructure (mainly porosity) on the migration of chlorides was evaluated. The concentration of chlorides was monitored by measuring the conductivity of the anolyte, which was distilled water initially. In addition, the estimation of the diffusion coefficients of the chloride ions in steady and non-steady conditions, Ds and Dns, was obtained from the ‘‘time-lag’’ and ‘‘equivalent time’’ measurements. The results showed that a gradual increase in the porosity of the concrete matrix is proportional to the migration rate of chloride, however, this relationship is not linear.

Online publication: 2013
Publication Type: full_text
Public price (Euros): 0.00