Abstract
In oder to investigate the crack propagation characteristics of thermally tempered glass, its fracture pattern has been studied by using disk samples having various diameters. The peculiar point, in which the fragment density changed discontinuously itself, was observed, and it was coincided with a point of the collision between the fracture front and the elastic wave from the edge of the glass plate, assuming the fracture velocity being 1.5×103m/sec and the elastic wave 3.3×103m/sec. The occurrence of spline depended upon the tensile value, two principal stresses, the initial fracture energy and the interaction with elastic wave and fracture front.
