Static Fatigue Test by Diametral Compression in Soda-Lime Glass DIsk Specimen

In order to study the static fatigue behavior of soda-lime glass, disk specimens with an indented-induced flaw at the center were fractured under a constant load applied by a diametral compression of the disk, where a transverse tensile stress across the loaded diameter was present, with the compressive stress acting in the direction of loading. Equibiaxial tension static fatigue tests were also conducted by loading a disk with concentric rings to examine the effect of the stress applied parallel to the crack. Although the scatter in these fatigue data was large, the time-to-failure increased with decreasing applied stress, and the degree of the increase was significantly lower in the diametral compression loading. This suggests that the nominal compressive stress applied parallel to the initial crack plane causes intensified tensile stress at the crack tip blunted by the annealing process, and promotes the occurrence of a sharp crack.