Stress Type Selection Commands

2.8.1. FACT Command

Specifies a factor to be applied to the stresses from the loadcases defined by subsequent execution commands (AVST, PRST, SHRS, WOOD and REIN) or loadcases referred to with the ADDC command.

Parameters

FACT : keyword

factor : scaling factor to be applied to subsequent loadcases. (Real) Note

The factor remains on the selected loadcases until it is overwritten by another FACT command.

The default value is 1.0 Example

FACT 105.0

2.8.2. AVST Command

Specifies the loadcases for which average stresses are to be calculated.

Parameters FACT

factor

AVST

loadcase END

ALL

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AVST : keyword

loadcase : loadcase number to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current block of averaged stress data. If the list of loadcase numbers continues onto subsequent lines, END is required on last line only.

ALL : keyword to indicate that all loadcases are selected.

Notes

1. If AVST and PRST commands are both omitted then the averaged stresses and principal stresses (if applicable) will be calculated for all loadcases in the ASAS run.

2. For BRICK, AXIS and HARM data types, the von Mises equivalent stress is calculated during printing of average nodal stresses. The formulae are given in Appendix C-.

If the von-Mises equivalent stress exceeds the allowable value set by a previous VONM command (see Section 2.10.2) the factor by which the allowable value is exceeded is also printed.

Example

(i) AVST

1 4 6 END

(ii) AVST

ALL

2.8.3. FANM Command (SHELL data only)

Specifies the loadcases for average stress calculation where FORCES and MOMENTS are required, as opposed to surface stresses.

Parameters FANM

loadcase END

ALL

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FANM : keyword

loadcase : loadcase number to be processed. (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current block of force and moment data. If the list of loadcase numbers continues onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

Notes

1. If FANM is specified, the nodal averaged values are output as force/unit length and moment/unit length instead of stresses at the top, middle and bottom surfaces.

2. For TRB3 elements this command will produce summed through thickness shears for each node.

3. FANM only controls the type of values output. AVST is also needed if nodal averaged values are required.

Example

FANM

1 3 END

2.8.4. BANM Command (SHELL data only)

Specifies the loadcases for average stress calculation where BENDING and MEMBRANE stresses are required, as opposed to surface stresses.

Parameters

BANM : keyword BANM

loadcase END

ALL

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loadcase : loadcase number to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current block of bending and membrane stress data. If the list of loadcase numbers continues onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

Note

1. If BANM is specified, the nodal averaged values are output in the form of bending and membrane stresses instead of stresses at the top, middle and bottom surfaces.

2. BANM only controls the type of values output. AVST is also needed if odal averaged values are required.

Example

BANM

4 -6 END

2.8.5. PRST Command

Specifies the loadcases for which principal stresses are to be calculated.

Parameters

PRST : keyword

loadcase : loadcase number to be processed. (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current block of principal stress data. If the list of loadcase numbers continues onto subsequent lines, END is required on last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

PRST

loadcase END

ALL

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Notes

1. If AVST and PRST commands are both omitted then the averaged stresses and principal stresses will be calculated for all loadcases in the ASAS run.

2. During the processing of principal stresses for solid elements (including axi-symmetric) the Tresca stress and von Mises equivalent stress are calculated. The formulae are given in Appendix C-.

3. For SHELL data, P₃ is the through thickness stress and is equal to zero, and hence the Tresca stress becomes the greater of the P₁, P₂ or P₁ - P₂ values. This value of Tresca stress is flagged with an asterisk in the printout but not printed separately.

4. The von-Mises equivalent stress is not printed but if the PRVM command is specified, the value is written to the plot file. See Section 2.8.6 and A.12.

5. PRST may not be used with the SBEAM data type.

Example PRST

5 2 1 END PRST

ALL

2.8.6. PRVM Command

Specifies the loadcases for which von-Mises equivalent stresses are to be processed.

Parameters

PRVM : keyword

loadcase : loadcase number to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

PRVM

loadcase END

ALL

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END : keyword to denote the end of the current block of von-Mises data. If the loadcase numbers continue onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

Notes

1. This command must be used in conjunction with the PRST command, see section 2.8.5.

2. The von-Mises stress is not printed for shell elements even when the PRVM command is used.

3. The PRVM command causes the von-Mises stresses to be written to the plot file.

4. The formulae used to calculate the von-Mises stress are given in Appendix C-.

Example

PRVM

3 7 9 END

2.8.7. SHRS Command (SHELL data only)

Specifies the loadcases for which average out of plane shear force/unit lengths are to be calculated.

Parameters

SHRS : keyword

loadcase : loadcase number to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current block of SHRS data. If the loadcase numbers continue onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

SHRS

loadcase END

ALL

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Notes

1. This command should not be used for TRB3 elements which are covered separately by the SECT command in Section 2.12.1 (see also Section 1.7)

2. SHRS only controls the type of values output. AVST is also needed if nodal averaged values are required.

Example

SHRS

3 7 9 END

2.8.8. WOOD Command (SHELL data only)

Specifies the loadcase numbers for which Wood-Armer moments are to be calculated. Only valid for SHELL data and element types GCS6, GCS8, TCS6, TCS8, TBC3, QUS4, SLB8 and TRB3.

Parameters

WOOD : keyword

loadcase : loadcase numbers to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current list of loadcases. If the list of loadcase numbers continues onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

Notes

1. The formulae used for calculating Wood-Armer moments are given in Appendix C-.

WOOD

loadcase END

ALL

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2. If Wood-Armer moment envelopes are required, the WDME combination type should be used on an ADDC/ADDF command (see Section 2.7.2/2.7.3).

3. Specifying WOOD for a loadcase will automatically invoke the FANM command, unless BANM has been specified, in which case Wood-Armer stresses are produced.

Example

WOOD

5 3 END

2.8.9. REIN Command (SHELL data only)

Specifies the loadcase numbers for which reinforcement areas are to be calculated. Only valid for SHELL data and element types GCS6, GCS8, TCS6, TCS8, TBC3, QUS4, SLB8 and TRB3.

Parameters

REIN : keyword

loadcase : loadcase numbers to be processed (Integer). This must either appear in the original ASAS analysis or be defined in a NEWC command.

END : keyword to denote the end of the current list of loadcases. If the list of loadcase numbers continues onto subsequent lines, END is required on the last line only.

ALL : keyword to indicate that all loadcases are selected. END is not required.

Notes

1. The formulae used for calculating Reinforcement Areas are given in Appendix C-.

REIN

loadcase END

ALL

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2. If reinforcement area envelopes are required, the REEN combination type should be used on an ADDC/ADDF command (see Section 2.7.2/2.7.3).

3. Specifying REIN for a loadcase will automatically invoke the FANM command.

Example

REIN

5 3 END

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