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+---
+type: concept
+title: "Midas FEA Concrete Cracking and Material Models"
+created: 2026-06-02
+updated: 2026-06-02
+address: c-000149
+aliases:
+  - MIDAS FEA material models
+  - midas FEA concrete cracking
+  - midas FEA total strain crack model
+tags:
+  - concept
+  - finite-element-method
+  - material-models
+  - concrete
+  - plasticity
+  - nonlinear-analysis
+  - midas-fea
+status: current
+related:
+  - "[[Midas-FEA-Analysis-Manual|Midas FEA Analysis Manual]]"
+  - "[[Finite Element Plasticity]]"
+  - "[[Plasticity Yield Criteria]]"
+  - "[[Plastic Flow Rules and Hardening]]"
+  - "[[Abaqus Constitutive Integration]]"
+  - "[[Abaqus Geomaterial and Concrete Plasticity]]"
+sources:
+  - "[[Midas-FEA-Analysis-Manual|Midas FEA Analysis Manual]]"
+---
+
+# Midas FEA Concrete Cracking and Material Models
+
+## Definition
+
+Midas FEA concrete cracking and material models are the material-library features used to represent elastic-plastic behavior, total strain cracking, compression and tension models, shear transfer, interface nonlinearity, and concrete-related path dependence.
+
+## How It Works
+
+The manual presents plasticity through elastic-plastic strain decomposition, yield functions, flow rules, hardening, and rate-form integration. It distinguishes associated and non-associated flow, noting that non-associated flow is often used for pressure-dependent concrete or geomaterial behavior when associated flow would produce excessive volumetric dilation.
+
+The total strain crack model thread covers loading and unloading, crack strain change, stiffness construction, compression behavior, tension behavior, shear behavior, and lateral effects. Interface material laws then add discrete cracking, crack dilatancy, bond-slip, Coulomb friction, and combined cracking-shearing-crushing for jointed or masonry-like behavior.
+
+## Important Solver Implications
+
+- Yield functions, plastic potentials, hardening variables, and integration schemes must be tied to integration-point state.
+- Non-associated flow can make the material stiffness nonsymmetric, which affects equation solver choice.
+- Crack and interface laws need state variables for opening, slip, unloading, shear retention, and damage-like softening.
+- For custom implementation, compare stress, internal force, reaction, displacement, and material state variables against a reference solver rather than checking displacement only.
+
+## Connections
+
+- [[Finite Element Plasticity]], [[Plasticity Yield Criteria]], and [[Plastic Flow Rules and Hardening]] give the generic plasticity theory.
+- [[Abaqus Constitutive Integration]] gives the parallel material-point update concept in Abaqus.
+- [[Abaqus Geomaterial and Concrete Plasticity]] is the closest Abaqus material-family counterpart.
+