Prediction method for degree of rebar corrosion in reinforced concrete by thermography

Author(s): T. Imai and H. Oshita
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: 233 - 240
Total Pages: 8
Language: English

Abstract: 
In recent years, the early deterioration of RC structures has become a social problem. Much more attention is paid now to rebar corrosion, because it causes a reduction of the structural performance. Therefore, it is important to predict the degree of the rebar corrosion by non destructive testing methods. However, there are no methods that quantitatively predict the degree of rebar corrosion.
In this study, we proposed using infrared thermography and electromagnetic induction as a new non-destructive testing method for the detailed evaluation of the rebar corrosion in RC structure. The details of proposed methods are shown below: Heat is generated in the rebar of a RC structure subject to electromagnetic induction. The surface temperature of the concrete, which increases by the heat transmitted from the rebar, is photographed by a thermography camera.
In general, the specific heat of the corrosion product is higher, and its thermal conductivity is lower. Hence, the corrosion product can be regarded as a kind of insulation. Therefore, when the rebars are heated equally, the surface temperature of concrete in which rebar is corroded is lower than that of the concrete in which rebar isn’t corroded. The result of our experiment shows that it is feasible to use the proposed method.

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