Hundred years after the first triaxial test
It was more than hundred years ago, when Theodore von Kármán (born as Tódor Kármán) designed and developed the first triaxial cell for investigation of brittle rocks behavior. His first research was based on Carrara marble and Mutenberg sandstone with varying confining pressures up to 600 MPa, demonstrating changes from brittle stages to ductile behavior in addition to hardening. The target of this paper is to give tribute to his development and work on this topic, having inspired and influenced many people in rock engineering and geophysical sciences, among others. After a short historical overview of this research the published data are recalculated using different empirical failure criteria which are widely used in the rock mechanics and rock engineering practice. For the recalculation and description of Kármán´s triaxial tests the original Hungarian paper was used.