Holz als Roh- und Werkstoff

, Volume 53, Issue 5, pp 339–345 | Cite as

Investigations into the photodegradation of wood using microtensile testing

Part 1: The application of microtensile testing to measurement of photodegradation rates
  • H. Derbyshire
  • E. R. Miller
  • H. Turkulin
Originals

Abstract

This paper demonstrates that the measurement of loss of microtensile strength of thin Scots pine sapwood strips exposed to solar radiation is a consistent and reliable means of determining photodegradation rates for wood. Careful selection and preparation of material is shown to be effective in reducing levels of variability. Photodegradation rates obtained by exposure to natural weathering are compared with rates obtained by exposure to artificial weathering in three different artificial weathering machines. Artificial weathering is shown to be a valid means of representing natural weathering and can provide the basis for the systematic investigation of the mechanisms of photodegradation. The results indicate the spectral distribution of the radiation output of the lamp and the moisture conditions during exposure are important influences on degradation rates.

Keywords

Degradation Rate Strength Loss Thin Strip Span Test Natural Weathering 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Untersuchung des Photoabbaus von Holz mit Hilfe einer Mikro-Zugfestigkeitsprüfung. Teil 1: Anwendung der Mikro-Zugfestigkeitsprüfung zum Messen der Abbaurate beim Photoabbau

Zusammenfassung

Diese Arbeit zeigt, daß die Mikro-Zugfestigkeitsprüfung eine geeignete und zuverlässige Methode ist, um die Abbaurate des Holzes beim lichtinduzierten Abbau zu messen. Durch sorgfältige Probenauswahl kann die Fehlerbreite verringert werden. Die Abbauraten bei natürlicher und künstlicher Bewitterung mit drei verschiedenen Apparaturen wurden verglichen. Die künstliche Bewitterung kann den natürlichen Prozeß simulieren und erlaubt, somit die Untersuchung der Abbaumechanismen. Die spektrale Verteilung der benutzten Strahler und die Feuchtegehalte während der Bewitterung beeinflussen sehr stark die Abbauraten.

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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • H. Derbyshire
    • 1
  • E. R. Miller
    • 1
  • H. Turkulin
    • 2
  1. 1.Building Research EstablishmentWatfordUK
  2. 2.Faculty of ForestryUniversity of ZagrebZagrebCroatia

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