Flaw statistics and the influence of non-linear deflections on the bending strength of brittle beams

Publisher Website
Google Scholar
Abstract
It is well known that the bending strength of a brittle beam decreases as the beam is made longer. Since this effect cannot be explained in terms of linear elastic fracture mechanics, it has traditionally been accounted for by Weibull statistics, in which the probability of finding a critical flaw increases with the volume of material under stress. This paper demonstrates that such a flaw-statistics explanation may be oversimplified because there is another contribution to cracking, previously ignored, which arises from the non-linear deformation of a bent beam. When this non-linear contribution to the fracture mechanics is considered, it is found that the bending strength of a beam is predicted to decrease as the beam lengthens, in close accord with experimental results on polymethylmethacrylate beams.

This publication has 16 references indexed in Scilit: