ABSTRACT
This result can be obtained only at short spans on the order of 0.5-1 mm. At these spans, the structural deformation is inhibited and fiber compression failure controls the strength. Figures 11-13 show the compression failure zones for wood and paper, revealing that the compression failure occurs on a scale much smaller than fiber length. The mechanism of failure does not change with gauge length, showing that the strength plateau in Figs. 17-19 is in fact the material strength. This effect should not be compared to the so-called zero-span tensile value which is aimed at evaluating the fiber strength in tension. In the zero-span test the tensile strength monotonically increases with decreasing span all the way down to zero span, indicating a change in failure mechanism with gauge length [10].
