--- type: concept title: "Plasticity Yield Criteria" complexity: advanced domain: computational-mechanics created: 2026-06-02 updated: 2026-06-02 address: c-000134 aliases: - yield surface - plastic yield functions - Tresca yield criterion - von Mises yield criterion - Mohr-Coulomb yield criterion - Drucker-Prager yield criterion tags: - concept - finite-element-method - plasticity - constitutive-modeling status: current related: - "[[Finite Element Plasticity]]" - "[[Plastic Flow Rules and Hardening]]" - "[[Abaqus Metal Plasticity Models]]" - "[[Abaqus Geomaterial and Concrete Plasticity]]" - "[[Plane Stress and Plane Strain Elements]]" - "[[Axisymmetric Finite Elements]]" sources: - "[[Finite-Elements-in-Plasticity-Theory-and-Practice|Finite Elements in Plasticity: Theory and Practice]]" --- # Plasticity Yield Criteria ## Definition A plasticity yield criterion defines the stress states at which a material leaves elastic response and begins plastic flow. In finite element analysis, the yield function is evaluated at integration points during each increment. ## Criteria In The Source [[Finite-Elements-in-Plasticity-Theory-and-Practice|Finite Elements in Plasticity: Theory and Practice]] emphasizes four criteria for two-dimensional and axisymmetric plasticity programs: - Tresca: pressure-insensitive yielding based on maximum shear stress. - von Mises: pressure-insensitive yielding based on distortional energy or deviatoric stress invariant. - Mohr-Coulomb: pressure-dependent yielding commonly used for frictional geomaterials. - Drucker-Prager: smooth pressure-dependent approximation useful for soils, rocks, and other frictional media. ## Solver Consequences The yield criterion affects: - how elastic trial stresses are tested; - where plastic corrections are projected; - whether the yield surface has corners or singular points; - whether pressure contributes to yielding; - which stress components and invariants must be computed in each element routine. ## Connections Pressure-insensitive criteria connect directly to [[Abaqus Metal Plasticity Models]]. Pressure-dependent criteria connect to [[Abaqus Geomaterial and Concrete Plasticity]]. All criteria depend on [[Plastic Flow Rules and Hardening]] to define the post-yield strain increment and evolution of the yield surface. ## Sources - [[Finite-Elements-in-Plasticity-Theory-and-Practice|Finite Elements in Plasticity: Theory and Practice]]