Influence of concrete properties on the calibration of radar, ultrasonics and active thermography

Title: Influence of concrete properties on the calibration of radar, ultrasonics and active thermography
Author(s): C. Maierhofer, M. Krause, J. Wöstmann, M. Röllig, R. Arndt, D. Streicher, C. Kohl
Paper category : conference
Book title: RILEM Symposium on On Site Assessment of Concrete, Masonry and Timber Structures - SACoMaTiS 2008
Editor(s): L. Binda, M. di Prisco, R. Felicetti
Print-ISBN: 978-2-35158-061-5
e-ISBN: 978-2-35158-075-2
Publisher: RILEM Publications SARL
Publication year: 2008
Pages: 15 - 24
Total Pages: 10
Nb references: 14
Language: English

Abstract: Non-destructive testing methods like radar, ultrasonics and active thermography are mainly applied for the determination of geometrical parameters like thickness of structural elements and location and depth of inclusions inside structures. The accuracy of the quantitative data is influenced by the error of the determination of the propagation velocity of electromagnetic, elastic or thermal waves, which depend on the material properties, its homogeneity and the procedure of calibration.
For the systematic investigation of the influence of material properties of concrete, several concrete test specimens including voids and reinforcement were constructed.
The test specimens were varied by the stage of concrete hydration, amount and distribution of pores in the cement matrix, variation of aggregates including porous aggregates and steel fibres, and variation of density of reinforcement. Systematic measurements were performed with radar, ultrasonic echo and active thermography. The propagation velocity, the transfer function and the contrast of voids were determined in relation to the different parameters. The maximum influence of these parameters will be discussed.

Online publication: 2009-05-26
Publication type : full_text
Public price (Euros): 0.00