Mecanica de las grietas auto-afínes en hojas de papel fragilizado

The effect of self-affine roughness on crack mechanics is studied. Experiments were carried out using embrittled Xerox paper sheets as a model perfectly brittle material. Results of standard mechanical tests and fractal measurements are compared with predictions of classical linear elastic fracture mechanics (LEFM) and mechanics of self-affine cracks theories in an elastic material. It is found out that the second one provides quantitative agreement with experiments which dramatically differ from the predictions of LEFM. Hence, the necessity of revising the ASTM standards. The concept of "fractal fracture toughness" is introduced.