AFC

Asymmetrical Friction Connection

Theory

The AFC model is a bilinear hardening model with an unloading stiffness differs from the initial stiffness. The term AFC comes from "asymmetric friction connection" which is a type of energy dissipaters. But this model can be used in other applications.

Syntax

material AFCS (1) (2) (3) (4) (5)
material AFC02 (1) (2) (3) (4) (5)
# (1) int, unique tag
# (2) double, elastic modulus
# (3) double, yield stress
# (4) double, hardening modulus
# (5) double, unloading modulus

material AFC (1) (2) (3) (4) (5) (6) (7) (8)
material AFC01 (1) (2) (3) (4) (5) (6) (7) (8)
# (1) int, unique tag
# (2) double, elastic modulus
# (3) double, tension yield stress
# (4) double, tension hardening modulus
# (5) double, tension unloading modulus
# (6) double, compression yield stress
# (7) double, compression hardening modulus
# (8) double, compression unloading modulus

History Variable Layout

location	value
initial_history(0)	load_sign
initial_history(1)	max_strain
initial_history(2)	reverse_strain
initial_history(3)	start_strain
initial_history(4)	start_stress
initial_history(5)	end_strain
initial_history(6)	end_stress

Remarks

1. AFC02 is a wrapper of AFC01. It provides a symmetric behavior while AFC01 provides an asymmetric behavior.

Examples

material AFC02 1 100 10 5 200
materialTest1D 1 1E-3 150 25 125 100 100 200 100 300 125 150
exit

material AFC01 1 100 10 5 200 20 2 300
materialTest1D 1 1E-3 150 25 125 100 100 200 100 300 125 150
exit

material AFC02 1 100 10 .1 500
materialTest1D 1 1E-2 20 40 60 80 100 120 140 160 80
exit