Elastic MultiLinear

Description

The ElasticMultiLinear material is a model of multi-linear, elastic constitutive response and can be used anywhere a UniaxialMaterial object is expected in OpenSees.

Syntax

ops.uniaxialMaterial('ElasticMultiLinear',tag,'-strain',*strain,'-stress',*stress)
ops.uniaxialMaterial('ElasticMultiLinear',tag,eta,'-strain',*strain,'-stress',*stress)

Parameters

tag : integer Unique material identifer
strain : float[] Array containing strains for each point on the stress-strain curve. The strains should be increasing in magnitude
stress : float[] Array containing stresses for each point on the stress-strain curve

Optional Parameters

eta : float Damping modulus

Notes

The point (0,0) is not implicit in this model
The model does not mirror positive stress-strain behavior onto negative stress-strain response
If the magintude of the trial strain exceeds the minimum or maximum strain, the returned stress will be linearly extrapolated from the stress and tangent at the first or last point

Examples

strain = [-0.002,0,0.002,0.03,0.1]
stress = [-60,0,60,65,68]
ops.uniaxialMaterial('ElasticMultiLinear',1,'-strain',*strain,'-stress',*stress)

Additional Resources

OpenSees wiki page

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