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European Journal of Wood and Wood Products

, Volume 69, Issue 4, pp 619–631 | Cite as

Biological damage function models for durability assessments of wood and wood-based products in building envelopes

  • Mostafa NofalEmail author
  • Kumar Kumaran
Originals Originalarbeiten

Abstract

A durability assessment system that links an advanced computer model for structural and hygrothermal analysis with damage functions is currently being developed. The computational system has different modules that calculate the different structural and hygrothermal responses of wall systems. Outputs of these modules are input to the module of damage function models to calculate damage, performance and service-life of building envelopes. Details of biological damage functions implemented in the damage function module of IRC’s durability assessment system are presented. The biological damage functions trace deterioration in wood materials subjected to hygrothermal loads that favor fungal growth. The developments of the models are based on recent biological experimental data from the literature. Equations to calculate various parameters in the model are presented and the application of the developed models is demonstrated using air leakage of warm and humid indoor air in a typical wood-frame construction in Ottawa.

Keywords

Damage Function Wood Material Mold Growth Oriented Strand Board Building Envelope 
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.

Biologische Schadensakkumulationsmodelle zur Bestimmung der Dauerhaftigkeit von Holz und Holzwerkstoffen in Gebäudehüllen

Zusammenfassung

Derzeit wird ein System zur Beurteilung der Dauerhaftigkeit entwickelt, das ein fortschrittliches Computermodell für die statische und hygrothermische Berechnung mit Schadensfunktionen verbindet. Das Computersystem besteht aus verschiedenen Modulen, mit denen die verschiedenen statischen und hygrothermischen Eigenschaften eines Wandsystems berechnet werden. Die Ergebnisse dieser Module dienen als Eingangsgrößen für das Schadensakkumulationsmodell, mit dem die Schädigung und die Lebensdauer von Gebäudehüllen berechnet werden. Die biologischen Schadensfunktionen, die in das Schadensakkumulationsmodell des IRC Systems zur Beurteilung der Dauerhaftigkeit implementiert wurden, werden detailliert beschrieben. Die biologischen Schadensfunktionen bestimmen Schädigungen im Holzmaterial, das Pilzwachstum verursachender Belastung ausgesetzt war. Zur Entwicklung der Modelle werden aktuelle biologische Versuchsdaten aus der Literatur hergenommen. Gleichungen zur Berechnung verschiedener Parameter im Modell werden dargestellt und die Anwendung der entwickelten Modelle wird anhand der Konvektion von warmer und feuchter Innenraumluft durch eine typische Holzrahmenkonstruktion in Ottawa aufgezeigt.

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Building Envelope and Structure Program, Institute for Research in Construction (IRC)National Research Council Canada (NRC)OttawaCanada

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