modify wiki

2026-05-29 17:05:53 +09:00
parent b7f84e1c0f
commit b7b79e38b1
64 changed files with 3131 additions and 48 deletions
@@ -0,0 +1,54 @@
+---
+type: concept
+title: "Abaqus Constitutive Integration"
+complexity: advanced
+domain: computational-mechanics
+created: 2026-05-29
+updated: 2026-05-29
+address: c-000059
+aliases:
+  - Abaqus material integration
+  - material point integration
+  - constitutive update
+tags:
+  - concept
+  - finite-element-method
+  - constitutive-modeling
+  - nonlinear-analysis
+  - abaqus
+status: current
+related:
+  - "[[Abaqus Theory Manual]]"
+  - "[[Abaqus Analysis Procedures]]"
+  - "[[Nonlinear Finite Element Analysis]]"
+  - "[[Hybrid Incompressible Elements]]"
+sources:
+  - "[[Abaqus Theory Manual]]"
+---
+
+# Abaqus Constitutive Integration
+
+## Definition
+
+Abaqus constitutive integration is the material-point stress update process used at element integration points to advance stresses, internal variables, and material tangent terms during finite element analysis.
+
+## How It Works
+
+Element routines pass kinematic information to material calculations at integration points. Depending on the formulation, this may include deformation gradients, strain increments, rotations, temperature, field variables, and the previous material state. The constitutive update returns stresses, updated state variables, and, for implicit Newton solution, a material Jacobian contribution.
+
+For plasticity, the manual organizes material behavior through yield functions, flow potentials, hardening laws, rate dependence, and stress integration. A backward-Euler style integration with consistent linearization is central because the quality of the material tangent strongly affects Newton convergence.
+
+## Why It Matters
+
+Constitutive integration is where material theory becomes finite element stiffness and residual terms. Even if the mesh and global solver are appropriate, a poor stress update or inconsistent tangent can cause convergence problems, path errors, or incorrect dissipation.
+
+## Connections
+
+- [[Nonlinear Finite Element Analysis]] supplies the global residual and tangent iteration that depend on material-point updates.
+- [[Abaqus Analysis Procedures]] determines when and how material states are advanced.
+- [[Hybrid Incompressible Elements]] relies on constitutive separation of deviatoric and pressure-like response.
+
+## Sources
+
+- [[Abaqus Theory Manual]]
+