Abaqus Static Analysis Workflow
Complete workflow for static structural analysis - stress, displacement, and reaction forces under constant loads.
When to Use This Skill
Route here when user mentions:
- •"stress analysis", "structural analysis"
- •"how much will it deflect", "displacement"
- •"is this strong enough", "strength check"
- •"factor of safety", "safety factor"
- •"reaction forces", "support loads"
- •"simulate a load on this part"
Route elsewhere:
- •Time-varying loads, impact, vibration →
/abaqus-dynamic-analysis - •Natural frequencies, resonance →
/abaqus-modal-analysis - •Temperature effects, thermal stress →
/abaqus-coupled-analysis - •Heat transfer only →
/abaqus-thermal-analysis - •Parts touching, friction →
/abaqus-contact-analysis
Workflow Steps
Execute these skills in order:
| Step | Skill | Purpose |
|---|---|---|
| 1 | /abaqus-geometry | Create part and assembly |
| 2 | /abaqus-material | Define material properties |
| 3 | /abaqus-mesh | Generate finite element mesh |
| 4 | /abaqus-bc | Apply supports and constraints |
| 5 | /abaqus-load | Apply forces and pressures |
| 6 | /abaqus-step | Configure analysis step (optional - default is fine) |
| 7 | /abaqus-job | Run the analysis |
| 8 | /abaqus-odb | Extract results |
What to Ask User
Required Information
| Input | What to Ask |
|---|---|
| Geometry | "What are the dimensions? (e.g., 100x50x20 mm)" |
| Material | "What material? (Steel, Aluminum, or custom E/v)" |
| Supports | "How is it supported? (fixed face, pinned points, rollers)" |
| Loads | "What loads? (force magnitude, location, direction)" |
Optional (Has Defaults)
| Input | Default | Ask If |
|---|---|---|
| Mesh size | Auto-calculated | Stress concentrations present |
| Element type | C3D8R | Complex curved geometry |
| Nonlinear | OFF | Large deformation expected |
Key Decisions
Linear vs Nonlinear Analysis
| Condition | Setting | When |
|---|---|---|
| Small deformation, linear material | nlgeom=OFF | Displacements < 1% of part size |
| Large deformation or rotation | nlgeom=ON | Thin structures, rubber, cables |
| Yielding expected | nlgeom=ON + Plasticity | Stress > yield strength |
Default: Start with linear. Switch to nonlinear if convergence issues or large deformation.
What Results to Extract
| User Goal | Output Variables | Acceptance Criteria |
|---|---|---|
| Strength assessment | S (stress), MISES | MISES < yield stress |
| Stiffness check | U (displacement) | Max deflection acceptable |
| Support sizing | RF (reaction force) | Reactions match applied loads |
Validation Checkpoints
After Each Step
| Step | What to Verify |
|---|---|
| Geometry | Part has cells, no error messages |
| Material | Section assigned to all cells |
| Mesh | Node count OK (Learning Edition: <=1000) |
| BCs | At least one fixed constraint exists |
| Loads | Applied to correct surface/point |
| Job | Completes without errors in .sta file |
Results Sanity Checks
| Check | Expected |
|---|---|
| Reaction force sum | Approximately equals applied loads |
| Displacement magnitude | Physically reasonable |
| Stress pattern | Follows logical load path |
| Max stress location | At expected concentration points |
Troubleshooting
| Error | Cause | Solution |
|---|---|---|
| "Zero pivot" | Rigid body motion | Add more BCs to constrain all 6 DOFs |
| "Negative eigenvalue" | Buckling or instability | Check BCs, may need stabilization |
| "Too many increments" | Load too large | Reduce load or use more increments |
| "Equilibrium not achieved" | Convergence failure | Try smaller initial increment |
| "Memory exceeded" | Mesh too fine | Increase element size |
Feedback Loops
- •Mesh fails: Return to geometry, add partitions or simplify
- •Zero pivot error: Return to BCs, ensure all rigid body modes constrained
- •Unreasonable results: Verify material properties, check load direction/sign
- •Stress too high: Either design issue (expected) or incorrect BC/load setup
Code Patterns
For API syntax and code examples, see: