Coping with the effect of moisture on air-permeability measurements

Author(s): R. Torrent, F. Moro, A. Jornet
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: 489 - 498
Total Pages: 10
Language: English

Abstract: 
The coefficient of air-permeability kT, measured non-destructively by the so-called "Torrent Method", has gained acceptance as a suitable durability indicator of the as-built cover concrete and has been standardized in Switzerland (Standard SIA 262/1:2013 Annex E). The standard adopted the ND electrical impedance method to control the moisture of site concrete. This paper presents data of moisture changes (assessed gravimetrically, by ND Impedance and by Wenner electrical resistivity) of concrete cubes dried in the lab and in an oven at 50°C. In parallel, measurements of kT were conducted on the same cubes. The results confirm that the ND impedance is a suitable method to assess the surface moisture of concrete and that the upper limit of 5.5%, prescribed in SIA 262/1-E, is adequate. In terms of the kT values obtained, it corresponds, roughly, to 3 days drying at 50°C.

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