抄録
A simple theory is developed to explain the effect of hydrostatic pressure on the torsional strength of brittle solids which contain numerous flaws uniformly. The effect of hydrostatic pressure on the stress intensity factor for an internal crack is estimated, and the statistical treatment of brittle strength, developed by Weibull and extended by Oh et al., is used. The mean values of the torsional strength and fracture angle for solid- and hollow-cylinders under hydrostatic pressure are calculated. The torsional and tensile strength thus predicted are compared each other. The torsional strength and fracture angle of glass cylinders, which are supposed to contain only surface flaws, are also considered.
