TITLE

Electromagnetic testing method using tangential coil for measurement of covering thickness and diameter of rebars in concrete

AUTHOR(S)
Koido, Junji; Hoshikawa, Hiroshi
PUB. DATE
May 2000
SOURCE
AIP Conference Proceedings;2000, Vol. 509 Issue 1, p1723
SOURCE TYPE
Conference Proceeding
DOC. TYPE
Article
ABSTRACT
Reinforcing bar in concrete provide tensile strength of structure. So, a measurement of covering thickness and diameter of rebar is important in maintenance inspection of concrete structure. The electromagnetic testing are expected as the method that can estimate covering thickness and diameter of rebar simultaneously. Magnetic flux generated by an excitation coil must reach a rebar sufficiently, to estimate covering and diameter of rebar. However, conventional test coil systems, which had been previously designed in these works, were insufficient for that requirement. Therefore, a new mutual induction type test coil system was developed for measuring rebars. The system has two tangential excitation windings and they are connected differentially to generate concentrated magnetic flux around rebar. And two pickup coils, that are arranged co-axially and normal to rebar, are also connected differentially to eliminate unbalanced voltage for no existence of rebar. In addition, neural nets were employed to estimate covering and diameter of rebar. Signal from the test coil was given as input for neural nets. From the result of experiment, this new type of coil provides good characteristic for measuring covering and diameter. And the estimation accuracy by the neural nets are discussed. © 2000 American Institute of Physics.
ACCESSION #
6029197

 

Related Articles

  • Using NDT for thickness measurement of shotcrete rock support systems in underground mines. Guevremont, P.; Hassani, F. P.; Momayez, M. // AIP Conference Proceedings;2000, Vol. 509 Issue 1, p1701 

    Shotcrete is quickly becoming the economical material of choice for rock support systems in underground mines throughout Canada. Although shotcrete technology has gained acceptance in the mining industry, there are some problems which have emerged with respect to quality assessment and thickness...

  • FLEXIBLE AND ARRAY EDDY CURRENT PROBES FOR FAST INSPECTION OF COMPLEX PARTS. Marchand, B.; Decitre, J. M.; Casula, O. // AIP Conference Proceedings;2/22/2010, Vol. 1211 Issue 1, p385 

    Eddy Current is a powerful mean of detection of detects located in conductive parts. This technique has already proved great performances and brought solutions to different industrial issues in nuclear or aeronautics domains for instance. Probes used in Non Destructive Testing (NDT) are mainly...

  • Nondestructive Damage Characterization of Complex Aircraft Structures by Inverse Methods: Advances in Multiscale Models. Murphy, R. Kim; Sabbagh, Harold A.; Sabbagh, Elias H.; Zhou, Liming; Bernacchi, William; Aldrin, John C.; Forsyth, David; Lindgren, Eric // AIP Conference Proceedings;2016, Vol. 1706 Issue 1, p1 

    The use of coupled integral equations and anomalous currents allows us to efficiently remove 'background effects' in either forward or inverse modeling. This is especially true when computing the change in impedance due to a small flaw in the presence of a larger background anomaly. It is more...

  • An advanced method for determining the wall thickness in buildings. Mikhnev, V.; Lyubetskii, N.; Palto, A. // Russian Journal of Nondestructive Testing;Jan2005, Vol. 41 Issue 1, p34 

    A modified method for measuring thickness of structural elements in buildings using probing signals of variable frequency is considered. To increase the measurement accuracy, the use of an auxiliary coaxial probe, in addition to transmitting-and-receiving antennas, is proposed. A device is...

  • Ultrasonics Part 9. Compression wave techniques. Drury, J. C. // Insight: Non-Destructive Testing & Condition Monitoring;Jul2005, Vol. 47 Issue 7, p425 

    Discusses the compression wave techniques in calibrating timebase for no-destructive testing. Elements of the initial pulse of single-crystal probes; Problems in calibrating when using a twin-crystal probe; Examination of brazed and bonded joints of compression waves.

  • Modern acoustic techniques for testing concrete structures accessible from one side only. Schabowicz, K. // Archives of Civil & Mechanical Engineering (Elsevier Science);Sep2015, Vol. 15 Issue 4, p1149 

    This paper presents nondestructive methodologies for investigating selected geometrical and material imperfections in unilaterally accessible concrete structures by means of modern acoustic techniques. The imperfections include: improper structure thickness, delamination, large air voids and...

  • Estimation of Thickness of Concrete Slab Members using Impact Echo Method. S. U. Hong; Y. T. Lee; S. H. Kim; J. H. Na // Key Engineering Materials;2014, Vol. 605, p139 

    Recently, the interest in maintenance and repair of existing concrete structures have increased, and it is typical to use non-destructive testing methods such as rebound hardness test or ultrasonic pulse velocity method to execute maintenance and repair of structures efficiently. Many...

  • Non-Contact Thickness and Profile Measurements of Rolled Aluminium Strip Using EMAT. Hobbis, A.; Aruleswaran, A. // AIP Conference Proceedings;2006, Vol. 820 Issue 1, p1772 

    Accurate measurement of strip thickness is a very high priority for the aluminium rolled product industry. This paper presents the findings of trials to measure the thickness of aluminium strip using a send-receive, radially polarised Electromagnetic Acoustic Transducer (EMAT). A broadband EMAT...

  • Evaluation of Thickness Reduction in a Thin Plate Using a Non-Contact Guided Wave Technique. Won-Joon Song; Ik-Keun Park; Tae-Hyung Kim; Hyun-Mook Kim; Yong-Kwon Kim; Yong-Sang Cho // AIP Conference Proceedings;2006, Vol. 820 Issue 1, p150 

    Ultrasonic guided waves are widely being studied and successfully applied to various non-destructive tests with the advantage of a long range inspection. Recently, non-contact methods are also adopted and combined with the guided wave techniques. In this paper, an advanced technique for the...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics