Holz als Roh- und Werkstoff

, Volume 65, Issue 1, pp 7–16 | Cite as

Fracture mechanics models applied to delayed failure of LVL beams

  • Myriam ChaplainEmail author
  • Gerard Valentin


Several theories for modelling fracture and slow growth of a crack in wood have been developed. The various models may be differentiated by the specifically regarded stress levels, failure mechanisms and averaging procedures. This paper deals with the application of viscoelastic fracture mechanics models to predict delayed failure of a timber element in bending. Simulations are compared to experimental results of bending tests carried out on LVL (Laminated Veneer Lumber) notched beams. This analysis emphasizes the influence of the geometry and of the size of the beam as well as of the damage area on the delayed failure.


Stress Intensity Factor Crack Length Crack Velocity Creep Compliance Calibration Function 
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Bruchmechanische Modelle zur Beschreibung des Rissfortschritts bei Furnierschichtholz-Balken


Zur Modellierung des Bruchverhaltens und Rissfortschritts in Holz wurden bereits viele Theorien entwickelt. Die verschiedenen Modelle lassen sich anhand der jeweils betrachteten Spannungsniveaus, Bruchmechanismen und Mittelungsverfahren unterscheiden. Diese Arbeit beschäftigt sich mit der Anwendung viskoelastischer Bruchmechanikmodelle zur Beschreibung des Rissfortschritts in einem biegebeanspruchten Holzbauteil. Simulationsergebnisse werden mit den Ergebnissen aus Biegeversuchen an ausgeklinkten Furnierschichtholz-Balken verglichen. Dabei wird der Einfluss der Geometrie und der Größe der Balken sowie des Schädigungsbereichs an der Rissspitze auf den Rissfortschritt deutlich.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Laboratoire de Rhéologie du Bois de Bordeaux, UMR 5103CNRS/INRA/Université Bordeaux ICestas CedexFrance

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