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wiki/concepts/Midas FEA Heat Transfer and Hydration Analysis.md

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+---
+type: concept
+title: "Midas FEA Heat Transfer and Hydration Analysis"
+created: 2026-06-02
+updated: 2026-06-02
+address: c-000153
+aliases:
+  - MIDAS FEA hydration heat analysis
+  - MIDAS FEA heat transfer analysis
+  - midas FEA thermal stress analysis
+tags:
+  - concept
+  - finite-element-method
+  - heat-transfer
+  - thermal-stress
+  - concrete
+  - midas-fea
+status: current
+related:
+  - "[[Midas-FEA-Analysis-Manual|Midas FEA Analysis Manual]]"
+  - "[[Midas Civil Heat of Hydration and Thermal Stress Analysis]]"
+  - "[[Finite Element Heat Transfer and Field Problems]]"
+  - "[[Finite Element Thermal Stress Analysis]]"
+  - "[[Midas FEA Construction Stage Analysis]]"
+  - "[[Abaqus Multiphysics Coupling and Co-simulation]]"
+sources:
+  - "[[Midas-FEA-Analysis-Manual|Midas FEA Analysis Manual]]"
+---
+
+# Midas FEA Heat Transfer and Hydration Analysis
+
+## Definition
+
+Midas FEA heat transfer and hydration analysis models temperature evolution, hydration heat, equivalent age, thermal strain, and thermal stress in concrete structures.
+
+## How It Works
+
+The general heat-transfer part covers the heat equation, heat-transfer elements, initial temperature, fixed temperature, heat flux, convection, heat generation, and staged heat-transfer results. The hydration heat part couples heat transfer to concrete material development and thermal stress analysis.
+
+The manual uses equivalent age to connect temperature history to strength and material evolution. Thermal stress outputs include nodal displacement, element stress, tensile strength by equivalent age, and crack ratio. Crack ratio is treated as a comparison between allowable tensile stress and generated tensile stress.
+
+## Solver Development Notes
+
+- Keep temperature as a field variable with its own boundary conditions and time history.
+- Define whether thermal stress is solved sequentially from a temperature field or coupled in one analysis.
+- Preserve concrete age and temperature history when construction stages activate or transfer state.
+- Include thermal-stress verification cases with free expansion, constrained expansion, transient heat flow, and hydration heat.
+
+## Connections
+
+- [[Finite Element Heat Transfer and Field Problems]] covers the general FE field-equation context.
+- [[Finite Element Thermal Stress Analysis]] gives the thermal strain and equivalent force viewpoint.
+- [[Midas FEA Construction Stage Analysis]] provides the staged concrete context.
+- [[Midas Civil Heat of Hydration and Thermal Stress Analysis]] provides the bridge/civil counterpart for equivalent age, maturity, shrinkage, creep, and thermal stress.