Influence of anisotropy on the energy release rate GI for highly orthotropic materials

Kossakowski, P. G.

Artykuł - szczegóły

Tytuł artykułu

Influence of anisotropy on the energy release rate GI for highly orthotropic materials

Autorzy

Kossakowski P. G.

Treść / Zawartość

Pełne teksty:

httpwww_ptmts_org_plkossakowski-4-07.pdf

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Warianty tytułu

Wpływ anizotropii na współczynnik uwalniania energii GI dla materiałów wysokoortotropowych

Języki publikacji

Abstrakty

The paper presents results of a numerical analysis concerning the energy release rate, GI, for highly orthotropic materials such as composites, laminates or wood. The values of GI were calculated using the Adina v. 8.1 Finite Element Method (FEM) program. Different material models were considered to establish the influence of anisotropy on GI. Two-dimensional (2D) and three-dimensional (3D) isotropic and anisotropic models were employed to study the performance of a Double Cantilever Beam (DCB) with various crack length-to-thickness ratios. It was reported that the smaller the ratio, the bigger the difference between the energy release rates GI calculated for the isotropic and anisotropic (transversal isotropic and orthotropic) material models. Thus, it is important that a fracture or fracture toughness analysis should be based on the transversal isotropie and orthotropic models and it should take into account anisotropy.

W artykule przedstawiono wyniki analizy numerycznej dotyczącej współczynnika uwalniania energii GI dla materiałów wysokoortotropowych takich jak kompozyty, laminaty czy drewno. Współczynnik GI obliczano przy użyciu programu Adina v. 8.1 opartego na metodzie elementów skończonych (MES). Określając wpływ anizotropii na GI, przyjmowano różne modele materiałowe. Podczas analizy użyto dwuwymiarowych (2D) i trójwymiarowych (3D) modeli numerycznych próbek podwójnie wspornikowych (ang. Double Cantilever Beam - DCB) o różnych proporcjach długości pęknięcia do grubości elementu. Zauważono, że im te proporcje są mniejsze, tym większe są różnice pomiędzy współczynnikami GI obliczanymi przy założeniu izotropowego i anizotropowych modeli materiałowych (transwersalnie izotropowych i ortotropowych). Dlatego też analiza pękania czy odporności na pękanie powinna być oparta na modelach transwersalnie izotropowych lub ortotropowych oraz powinna być uwzględniana anizotropia materiału.

Słowa kluczowe

fracture toughness pinewood highly orthotropic materials energy release rate GI

odporność na pękanie drewno sosnowe materiały wysokoortropowe współczynnik uwalniania energii GI

Wydawca

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Czasopismo

Journal of Theoretical and Applied Mechanics

Rocznik

2007

Tom

Vol. 45 nr 4

Strony

739--752

Opis fizyczny

Bibliogr. 36 poz., rys., tab.

Twórcy

autor

Kossakowski P. G.

Kielce University of Technology, Faculty of Civil and Environmental Engineering, Kielce, kossak@tu.kielce.pl

Bibliografia

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Typ dokumentu

Bibliografia

Identyfikator YADDA

bwmeta1.element.baztech-article-BWM4-0004-0011