Mode I Critical Stress Intensity Factor of Beech Wood (Fagus Sylvatica) in a TL Configuration: A Comparison of Different Methods

Abstract

The paper presents a comparison between various methods of mode I critical stress intensity factor KIC calculations of beech wood in the TL configuration. The first method is the stress intensity factor extrapolation to the distance of 0 mm from the crack tip; the second method is the use of the J integral; and the third method is based on the differences in deformation energies from which the strain energy release rate per unit of crack propagation length was obtained. The fourth method is the calculation of material deformation around the crack or the displacement of the triangle element node; and the fifth method uses a generally known equation for the CT specimen for plane-strain conditions in isotropic material. Using the finite element method, it was found that the J integral was least sensitive to the size and shape of the elements. It was used to calculate the critical stress intensity factor KIC for beech wood in a TL configuration. The average value is 0.56 MPa√m with a standard deviation of 0.047 MPa√m

Relationship between crack propagation and the stress intensity factor in cutting parallel to the grain of hinoki (Chamaecyparis obtusa)

“…On the other hand, the theory and method of the fracture mechanics have been applied to understand fracture of inhomogeneous materials [16,17] and also to wood, and its relationship to the strength, anatomical features and quality of wood. The outline of the series of the works can be seen in the recent reviews [18,19]. Many of the previous works have concentrated on the values of stress intensity factor K I or fracture toughness K IC of wood for the mode I fracture [20][21][22][23][24][25][26][27][28][29].…”

Madera termo-tratada de frondosas para uso estructural

“…Merhar et al ( 2013) [268] compararon cinco métodos diferentes para determinar el factor de intensidad de tensiones crítico, K Ic , en muestras CT de haya. El método J -integral resultó ser el más adecuado teniendo en cuenta su simplicidad y su menor sensibilidad a la forma y tamaño de los elementos nitos implementados en el análisis.…”