European Journal of Wood and Wood Products

, Volume 69, Issue 4, pp 605–617 | Cite as

Assessment of glued timber integrity by limited-angle microfocus X-ray computed tomography

  • Sergio J. Sanabria
  • Peter Wyss
  • Juerg Neuenschwander
  • Peter Niemz
  • Urs Sennhauser
Originals Originalarbeiten


Glued timber products have an extensive range of applications in construction. In this work a Microfocus X-ray Computed Tomography method was developed to inspect gluing defects in timber samples and was applied successfully on experimental data. The bonding plane was segmented into glued and non-glued regions and imaged with 5 mm resolution. Moreover, the gap topology between timber lamellas was precisely characterised. A limited-angle reconstruction with anisotropic frame binning together with a specific glue line readout method efficiently filters out undesired wood structure highlighting the information of the adhesive joint. This method imposes limitations on the size of the specimen in only one dimension. The presence and absence of glue could be detected for glue line thicknesses over 50 μm and air gaps larger than 150 μm could be characterised. Several information reduction approaches were combined in the reconstruction process to implement the assessment of a 100×100 mm2 bonding plane in less than 40 s.

Detektion von Fehlverklebungen in Holzbauteilen mittels Mikrofokus Röntgen-Computertomographie


Holzverklebungen gewinnen zunehmend an Bedeutung. Im Rahmen dieser Arbeit wurde ein Mikrofokus Röntgen-Computertomographie Messverfahren zur Beurteilung von Fehlverklebungen in Holzbauteilen entwickelt und in experimentellen Versuchen erfolgreich überprüft. Fehlverklebungen und die Topologie der Klebfugen wurden mit einer räumlichen Auflösung von 5 mm abgebildet. Verfahrensspezifische Bildrekonstruktions- und Klebfugen-Auslesealgorithmen mit eingeschränktem Aufnahmewinkelbereich filtern unerwünschte Holzstrukturen heraus und heben die Leimschicht hervor. Die Größe der Holzbauteile ist bei diesem Messverfahren nur in einer Dimension beschränkt. Die An- und Abwesenheit von Klebstoff lässt sich für Leimfugen dicker als 50 μm nachweisen; Luftspalten größer als 150 μm sind feststellbar. Die Informations-Reduktionsverfahren ermöglichten die Beurteilung von 100×100 mm2 verleimten Holzoberflächen in einer Messzeit von weniger als 40 s.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Sergio J. Sanabria
    • 1
  • Peter Wyss
    • 1
  • Juerg Neuenschwander
    • 1
  • Peter Niemz
    • 2
  • Urs Sennhauser
    • 1
  1. 1.Electronics/Metrology/Reliability Laboratory, EmpaSwiss Federal Laboratories for Materials Science and TechnologyDuebendorfSwitzerland
  2. 2.Institute for Building Materials, Wood PhysicsETH ZurichZurichSwitzerland

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