ArcLength Integrator

The ArcLength integrator is a static integration method that follows the equilibrium path using the arc length method.

Description

This integrator is particularly suitable for:

  • Post-buckling analysis of structures

  • Problems with snap-through or snap-back behavior

  • Tracing complex load-displacement paths

  • Cases where load or displacement control fails

  • Highly nonlinear structural problems

The ArcLength method uses a constraint equation based on the arc length along the load-displacement path, allowing it to navigate both load and displacement reversals.

Parameters

The ArcLength integrator requires the following parameters:

Parameter

Description

Default

Notes

s

Arc length

None

Required

alpha

Scaling factor on reference loads

None

Required

Usage Example

# Create an ArcLength integrator
integrator = fm.analysis.integrators.create_integrator("arclength",
                                                s=1.0,
                                                alpha=0.1)