Altenbach, H.H.AltenbachRosendahl, P.L.P.L.RosendahlBecker, W.W.BeckerKolupaev, V.A.V.A.Kolupaev2022-03-142022-03-142018https://publica.fraunhofer.de/handle/publica/402532In the theory of plasticity the existence of the yield surface is assumed. In the past, several yield surfaces were formulated. However, choosing an appropriate surface for a particular material remains challenging. The extremal yield figures for isotropic material behavior will be generalized in this paper for universal practical application. Measured data for concrete will be approximated with the help of the proposed criterion.enisogonal hexagonisotoxal hexagonextremal yield figureplasticityisotropic material behavior620conference paper