Displacement fields of wood in tension based on image processing: Part 1. Tension parallel- and perpendicular-to-grain and comparisons with isotropic behaviour.

Displacement fields for tensile loaded rubber and wood in paralleland perpendicularto-grain were obtained from digital image correlation. The results showed that the digital image correlation can reveal fine details of the nature of displacements in both rubber and wood. It was found that when load is perpendicular-to-grain, the lignin matrix produces uniform displacement fields similar to that of isotropic rubber. Uniform displacement fields also observed when lignin is involved in contraction due to Poisson effect in parallel-to-grain tension. However, when tracheids carry the load in parallel-tograin loading, or are compressed in perpendicular-to-grain loading, a complex displacement pattern distorted by internal shear stress and slippage is produced.

[1]  M. Sutton,et al.  Estimation of stress intensity factor by digital image correlation , 1987 .

[2]  W. H. Peters,et al.  Application of an optimized digital correlation method to planar deformation analysis , 1986, Image Vis. Comput..

[3]  Audrey G. Zink,et al.  Strain measurement in wood using a digital image correlation technique , 1995 .

[4]  M. Sutton,et al.  Application Of Digital Correlation Methods To Rigid Body Mechanics , 1983 .

[5]  W. F. Ranson,et al.  Determination of displacements using an improved digital correlation method , 1983, Image Vis. Comput..

[6]  S. McNeill,et al.  A study of mixed mode fracture by photoelasticity and digital image analysis , 1991 .

[7]  S. Samarasinghe,et al.  Study of Mode-I and Mixed-Mode fracture in wood using digital image correlation method , 1996 .

[8]  M. Williams,et al.  On the Stress Distribution at the Base of a Stationary Crack , 1956 .

[9]  M. Sutton,et al.  Effects of subpixel image restoration on digital correlation error estimates , 1988 .

[10]  Audrey G. Zink,et al.  Image Correlation Analysis of Multiple-Bolt Wood Connections , 1997 .

[11]  Hugh Alan Bruck,et al.  Digital image correlation using Newton-Raphson method of partial differential correction , 1989 .

[12]  J. L. Thorpe,et al.  Quantification of compression failure propagation in wood using digital image pattern recognition , 1996 .

[13]  P. C. Paris,et al.  On cracks in rectilinearly anisotropic bodies , 1965 .

[14]  G. Irwin.  ANALYSIS OF STRESS AND STRAINS NEAR THE END OF A CRACK TRAVERSING A PLATE , 1957 .

[15]  W. F. Ranson,et al.  Applications of digital-image-correlation techniques to experimental mechanics , 1985 .

[16]  Hiroshi Tada,et al.  The stress analysis of cracks handbook , 2000 .