Comparison of different failure approaches in knotty wood

• Autorzy: Guindos P.

Identyfikatory

DOI

10.12841/wood.1644-3985.065.03

• Języki publikacji: EN

Abstrakty

EN

This article presents and assesses 64 different ways for predicting the failure onset in knotty wooden beams. The aim is to provide engineers and modellers a general view of how to evaluate the failure in wooden structural members with knots. The studied criteria included both the conventional point-based and average stress theories. Special attention was paid to the effect of the elements of the wood mesostructure, i.e. knots and fiber deviation, which can generate singular stress concentrations as notches or cracks would do in fracture mechanics. The case study consisted of predicting the failure onset of bending in structural wooden beams. A previously validated finite element model was used in order to compute the heterogeneous stresses. It was found that the knots caused considerable stress singularities so that the size of the average stress theory influenced the failure predictions by up to 23%. However, the variations generated by distinct phenomenological criteria were in general much smaller. The application of the average stress theory in large stress integration volumes is strongly recommended when predicting the failure in wood members.

Słowa kluczowe

EN

average stress approach; failure prediction; knot; multi-scale modelling; phenomenological failure criterion

PL

naprężenie średnie; przewidywanie defektu; sęk; modelowanie wielkoskalowe; fenomenologiczne kryterium zniszczenia

• Wydawca: Sieć Badawcza Łukasiewicz - Poznański Instytut Technologiczny
• Czasopismo: Drewno : prace naukowe, doniesienia, komunikaty
• Rocznik: 2014
• Tom: vol. 57, nr 193
• Strony: 51--68
• Opis fizyczny: Bibliogr. 35 poz., rys., tab.

Twórcy

autor

Guindos P.

• Fraunhofer WKI – Institute for Wood Research, Braunschweig, Germany

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• List of standards
• DIN EN 408 [2010]: Timber structures – Structural timber and glued laminated timber – Determination of some physical and mechanical properties