Abaqus Amplitude Skill

Abaqus Amplitude Skill

This skill defines time-varying load and boundary condition profiles in Abaqus. Amplitudes act as multipliers that scale loads/​BCs over time.

When to Use This Skill

Route here when user mentions:

• "Gradually increase the load", "ramp up the force"
• "Cyclic loading", "sinusoidal excitation"
• "Pulse load", "impulse", "impact loading"
• "Time-varying boundary condition", "loading history"
• "Smooth transition", "avoid sudden load application"
• "Earthquake input", "harmonic excitation"

Route elsewhere:

• Constant static loads (no amplitude needed) → /​abaqus-load
• Initial conditions, predefined fields → /​abaqus-field
• Dynamic analysis setup → /​abaqus-dynamic-analysis

Workflow: Defining Amplitudes

Step 1: Understand User's Load Profile

Ask if unclear:

• What shape? Ramp, sinusoidal, pulse, decay, custom?
• What timing? Duration, frequency, peak time?
• What magnitude? Amplitude is a multiplier (0.0-1.0 typical)

Step 2: Choose Amplitude Type

Most common: TabularAmplitude with linear ramp (0,0) to (1,1)

Step 3: Determine Time Reference

Step 4: Define Data Points

For TabularAmplitude and SmoothStepAmplitude:

• Data is (time, amplitude_factor) pairs
• Time values must be strictly increasing
• Factor typically ranges 0.0 to 1.0 (can exceed if needed)
• Factor multiplies the load/​BC magnitude

Step 5: Apply to Load or BC

Amplitudes are referenced by name when creating:

• Loads: ConcentratedForce, Pressure, Gravity, etc.
• BCs: DisplacementBC, VelocityBC, etc.

Key Decisions

Common Load Profiles

Smooth vs. Tabular

What to Ask User

Validation Checklist

After defining amplitude:

• Time values are strictly increasing
• Factor range is appropriate (usually 0.0-1.0)
• timeSpan matches analysis intent (STEP vs TOTAL)
• Amplitude name matches what load/​BC references
• For dynamic: smooth transitions to avoid numerical shocks
• For periodic: frequency and coefficients are correct

Troubleshooting

Code Patterns

For API syntax and code examples, see:

• API Quick Reference - Full parameter details
• Common Patterns - Ready-to-use snippets
• Troubleshooting Guide - Error solutions