Training & Exercise Manual · 03.14

03.14 · Moisture expansion + structural load

Online chapter revision 2026-10-05. Complete download edition 2026-10-03.

MoistureChapter concept map · not simulation results
INPUTExposure + sorption
MODELMoisture transport
OUTPUTConcentration history

An environmental structural study is useful only if the temperature or moisture state used by the mechanical calculation is known. This exercise traces that handoff and compares the connected result with a deliberately controlled reference, so that changes in strain or ply stress can be attributed to the enabled contributions.

Open this exercise in Workbench

Used model inputs for 03.14 · Moisture expansion + structural load
Used records in the standard workflow layout. Hidden records remain in Workbench. This diagram is not a calculated result.
Physical process schematic: 03.14 · Moisture expansion + structural load
Moisture enters or leaves the laminate through its prescribed surface conditions. Compare surface concentration, uptake and through-thickness diffusion. Conceptual setup, not to scale or a solved result. The live process view remains available in Workbench.

Prepare the baseline

Follow each selected case to the shared laminate, noting its own schedule and reference state. Record which cases are actually connected; some examples include moisture without thermal loading or use different resin systems in the same stack. Follow the specified disconnection procedure for the reference run and check that no separate mechanical process link remains active unintentionally.

Worked procedure

1. Trace moisture conditioning and the structural load to their shared laminate; Thermal is not included.

2. Run and compare the moisture history and moisture-expansion contribution with a dry mechanical-only copy.

Review checkpoints

Thermal is deliberately disconnected.

Structural coupling uses the reported moisture state and reference moisture.

Model limits

Use the solver’s reported coupling state and limits. Do not assume this constitutes a general 3D coupled finite-element model or a calibrated cure-residual-stress prediction.

Interpret the comparison

Compare the transferred state as well as the mechanical outputs. Keep load, geometry and layup unchanged unless the task explicitly varies them, and explain whether the difference comes from free strain, state-dependent stiffness or another supported effect. Environmental exposure does not automatically imply strength degradation in every solver branch.

How information passes between models

Micro → Laminates: Predicted ply stiffness, strength, density and expansion properties.

Materials → Micro: Constituent stiffness, strength, density and thermal / moisture properties.

Mechanical → Simulation: SIMULATION selects this case and its analysis model; the case owns its applicable cycle and input references.

Laminates → Mechanical: Ply angles and thicknesses, stiffness, mass and ply properties.

Geometry → Mechanical: Part shape and dimensions, thickness or section definition, and model-specific geometric inputs. Each selected case consumes only the dimensions its model supports.

Moisture → Simulation: SIMULATION selects this case and its analysis model; the case owns its applicable cycle and input references.

Laminates → Moisture: Ply angles and thicknesses, stiffness, mass and ply properties.

Models → Micro: Applied model assignment: Halpin–Tsai. Model parameters and formulation are used by Micro.

Models → Mechanical: Applied model assignment: CLT · Linear static with failure indices. Model parameters and formulation are used by Mechanical.; Maximum stress

Models → Moisture: Applied model assignment: 1D transient moisture diffusion. Model parameters and formulation are used by Moisture.

Further reading and evidence

Review the recorded validation scope. Retain the original inputs and solver notices with the results. Representative teaching data are not design allowables.

References and source sections

References are retained with the formulations they support. Software instructions describe implementation scope; a cited source does not establish independent validation of a CDS calculation.

Detailed online sources