3.1.5.31. InitStress Material Wrapper

This command is used to construct an InitStress (or InitialStress) uniaxial material wrapper. The wrapper imposes an initial stress on the wrapped material. After the constructor, the wrapper passes through the wrapped material response with the initial stress offset.

uniaxialMaterial InitStress $matTag $otherTag $sig0

Argument	Type	Description
$matTag	integer	unique material tag
$otherTag	integer	tag of a previously-defined UniaxialMaterial
$sig0	float	initial stress

Note

Run one analysis step with dt = 0 (e.g. static with integrator LoadControl 0.0) so that initial stresses are in equilibrium.

Example

1. Tcl Code

uniaxialMaterial Hardening 1 3.0 1.0 0.1
uniaxialMaterial InitStress 2 1 0.3

2. Python Code

ops.uniaxialMaterial('Hardening', 1, 3.0, 1.0, 0.1)
ops.uniaxialMaterial('InitStress', 2, 1, 0.3)

Code developed by: Michael H. Scott