Home
Reference Guide
This manual provides a detailed list of all the input keywords and options available in Radioss.
LS-DYNA Input
This manual provides a list of LS-DYNA input files available in Radioss.
*INITIAL
*INITIAL_STRESS_SHELL_{OPTION}
LS-DYNA Input Interface KeywordDefines the reference state for elements belonging to a part, using given nodal coordinates.

Welcome
What's New
View new features for Radioss 2024.1.
Overview
Radioss^® is a leading explicit finite element solver for crash and impact simulation.
Tutorials
Discover Radioss functionality with interactive tutorials.
User Guide
This manual provides details on the features, functionality, and simulation methods available in Altair Radioss.
Reference Guide
This manual provides a detailed list of all the input keywords and options available in Radioss.
- File Extensions and Formats
  Current Radioss format uses the 12x extension format.
- Single File Input
  This format allows running either Starter or Engine with the same file.
- New Keywords in 2024
  New and modified features in Radioss.
- Starter Input
  This manual provides a list of all the model definition keywords and options available in Radioss.
- Engine Input
  This manual provides a list of all the solution definition keywords and options available in Radioss.
- LS-DYNA Input
  This manual provides a list of LS-DYNA input files available in Radioss.
  - *AIRBAG
  - *BOUNDARY
  - *CONSTRAINED
  - *CONTACT
  - *CONTROL
  - *DAMPING
  - *DATABASE
  - *DEFINE
  - *ELEMENT
  - *EOS
  - *HOURGLASS
    LS-DYNA Input Interface KeywordDefine solid and hourglass formulation for 8-node solid elements.
  - *INCLUDE
  - *INITIAL
    - *INITIAL_AXIAL_FORCE_BEAM
      LS-DYNA Input Interface KeywordDefines initial axial force applied to beams as function of time.
    - *INITIAL_FOAM_REFERENCE_GEOMETRY
      LS-DYNA Input Interface KeywordDefines the reference state for elements belonging to a part, using given nodal coordinates.
    - *INITIAL_STRAIN_SHELL
      LS-DYNA Input Interface KeywordInitializes the strain for shell elements in the global coordinate system.
    - *INITIAL_STRESS_SHELL_{OPTION}
      LS-DYNA Input Interface KeywordDefines the reference state for elements belonging to a part, using given nodal coordinates.
    - *INITIAL_VELOCITY
      LS-DYNA Input Interface KeywordDefines initial velocity of a node set.
    - *INITIAL_VELOCITY_GENERATION
      LS-DYNA Input Interface KeywordDefine both translational and rotational initial velocities.
    - *INITIAL_VELOCITY_NODE
      LS-DYNA Input Interface KeywordThis keyword defines an initial translational and rotational velocity of a node.
    - *INITIAL_VELOCITY_RIGID_BODY
      LS-DYNA Input Interface KeywordDefine initial velocity of a rigid body.
  - *INTEGRATION_SHELL
    LS-DYNA Input Interface KeywordDefine user-defined through the thickness integration rules for the composite shell element.
  - *KEYWORD
    LS-DYNA Input Interface KeywordThis keyword should always be the first card of the input file. Optionally used with *CONTROL_UNITS card to specify model units.
  - *LOAD
  - *MAT
  - *NODE
    LS-DYNA Input Interface KeywordDefines a node number and nodal coordinates in the global coordinate system.
  - *PART
    LS-DYNA Input Interface KeywordDefines a part, which combines material and property information.
  - *RIDIGWALL
  - *SECTION
  - *SET
- Optimization Keywords
  Optimization Keyword This manual contains the description of the keywords for the Radioss optimization. This manual is compatible with the version 2018 of Radioss.
- Multi-Domain
  This manual contains the description of the keywords for the Radioss Multi-Domain.
- Other Files
- Definition
Example Guide
This manual presents examples solved using Radioss with regard to common problem types.
Verification Problems
This manual presents solved verification models.
Frequently Asked Questions
This section provides quick responses to typical and frequently asked questions regarding Radioss.
Theory Manual
This manual provides detailed information about the theory used in the Altair Radioss Solver.
User Subroutines
This manual describes the interface between Altair Radioss and user subroutines.

View All Altair HyperWorks Help

*INITIAL_STRESS_SHELL_{OPTION}

LS-DYNA Input Interface KeywordDefines the reference state for elements belonging to a part, using given nodal coordinates.

Format

For OPTION = <BLANK>


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
*INITIAL_STRESS_SHELL
`EID`	`npg`	`nb_integr`			`LARGE`

For OPTION = SET


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
*INITIAL_STRESS_SHELL_SET
`SID`	`npg`	`nb_integr`			`LARGE`

Stress card for LARGE = 0


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)
`T`	`SIGXX`	`SIGYY`	`SIGZZ`	`SIGXY`	`SIGYZ`	`SIGZX`	`EPSP`

Stress card for LARGE = 1


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
`T`		`SIGXX`		`SIGYY`		`SIGZZ`		`SIGYZ`
`SIGZX`		`SIGZX`		`EPSP`

Definition


Field	Contents	SI Unit Example
`OPTION`	<BLANK> Define initial state for shell element. SET Define initial state for all element in the defined set of part.
`EID`	4 or 3 node shell element identifier. (Integer)
`SID`	Part set identifier. (Integer)
`npg`	Number of Gauss point in plane. = 1 Under-integrated element and 3 node shell element. = 4 Fully-integrated element. (Integer)
`nb_integr`	Integration point number through the thickness. (Integer)
`LARGE`	Format size. = 0 Regular format. = 1 Large format. (Integer)
`T`	Through thickness integration point parametric position between -1 and 1. (Real)
`SIGij`	Stress value in the direction ij. (Real)	$[Pa]$
`EPSP`	Plastic strain.

Comments

This keyword maps to /INISHE/STRS_F/GLOB or /INISH3/STRS_F/GLOB.
If npg=4, the Gauss integration points in the plane are stored in the following order:
$(- \frac{\sqrt{3}}{3}, - \frac{\sqrt{3}}{3}), (+ \frac{\sqrt{3}}{3}, - \frac{\sqrt{3}}{3}), (+ \frac{\sqrt{3}}{3}, + \frac{\sqrt{3}}{3}), (- \frac{\sqrt{3}}{3}, + \frac{\sqrt{3}}{3})$
One stress card is added for each integration through the thickness and each Gauss points.