Idealnie sprężysto-plastyczna tarcza o profilu hiperbolicznym

For a disk with hyperbolically variable thickness, the loading parameter at whitch inadmissible discontinuities of radial displacement ? occur, is evaluated. These discontinuities result from an infinite increase of the radial strain er. K. Szuwalski and M. Życzkowski [4] proposed to call that loading parameter the ,,decohesive carrying capacity''. To avoid infinitely large thickness at the centre of the disk, the paper considers a disk consisting of two parts: the inner of constant thickness, and the outer of hyperbolic profile. For a general case, when both parts are made of different materials, the possibility of initiation of the plastification process from either the radius of connection of both parts or the outer radius is investigated. For both cases the conditions of occuring inadmissible discontinuities of displacements are formulated, particularly when the plastic zone does not spread.