Multilinear1D

Uniaxial Multilinear Material Using J2 Plasticity

Syntax

material Multilinear1D (1) (2) (3) (4 5...)
# (1) int, unique material tag
# (2) double, elastic modulus
# (3) double, density
# (4 5...) double, pairs of stress and plastic strain

Remarks

1. No kinematic hardening is defined in this model.
2. The stress will be constant after the last point defined. This means the yield surface does not change its size after the last point. So the stiffness will be singular. This may cause instability issues in analysis.
3. The first plastic strain must be zero.

Usage

material Multilinear1D 1 50000 1. 0. 100 2E-3 120 4E-3 250 1E-2 200
materialTest1D 1 1E-4 120 120
exit

The above command defines the backbone using the following data.

plastic strain	stress
0E0	100
2E-3	120
4E-3	250
1E-2	200
	200

Examples