*SECTION STIFFNESS

Define stiffness properties for meshed general beam sections.

This option must be used in conjunction with the BEAM GENERAL SECTION, SECTION=MESHED option to assign the beam section stiffness properties that result from the two-dimensional meshed cross-section generation procedure. The properties are written to the jobname.bsp file during the cross-section generation and are typically read into a subsequent beam analysis using the INCLUDE option.

The SECTION STIFFNESS and SECTION INERTIA options are mutually exclusive with the second and third data lines of the BEAM GENERAL SECTION option. The SECTION STIFFNESS, FULL COUPLING option is also mutually exclusive with the TRANSVERSE SHEAR STIFFNESS, *CENTROID, and *SHEAR CENTER options. See Meshed Beam Cross-Sections for details.

This page discusses:

See Also
*BEAM GENERAL SECTION

Products Abaqus/Standard Abaqus/Explicit

Type Model data

LevelPartPart instance

Optional parameter in Abaqus/Standard

FULL COUPLING
Include this parameter to define a general beam section with full coupling between the six section strains (axial stretch, bending, torsion, and shear) in the constitutive relation. This includes all coupling effects that might otherwise be defined with the TRANSVERSE SHEAR STIFFNESS, *CENTROID, and *SHEAR CENTER options.

If this parameter is omitted, it is assumed that the section stresses only relate directly to the respective section strains, except for cross-bending and for the additional selective coupling effects that might be defined with the TRANSVERSE SHEAR STIFFNESS, *CENTROID, and *SHEAR CENTER options.

Data line if the FULL COUPLING parameter is omitted

First (and only) line

  1. Axial stiffness of the section, ( E ⁢ A ) .

  2. Bending stiffness about the 1-axis of the section, ( E ⁢ I ) 11 .

  3. Stiffness for cross-bending, ( E ⁢ I ) 12 .

  4. Bending stiffness about the 2-axis of the section, ( E ⁢ I ) 22 .

  5. Torsional constant, ( G ⁢ J ) .

Data lines if the FULL COUPLING parameter is included

First line

  1. Axial stiffness of the section, ( K ) 11 .

  2. Shear stiffness of the section in the first direction, ( K ) 22 .

  3. Shear stiffness of the section in the second direction, ( K ) 33 .

  4. Torsion stiffness, ( K ) 44 .

  5. Bending stiffness about the 1-axis of the section, ( K ) 55 .

  6. Bending stiffness about the 2-axis of the section, ( K ) 66 .

  7. Coupling stiffness of the section for axial stretch–shear in the first direction, ( K ) 12 .

  8. Coupling stiffness of the section for axial stretch–shear in the second direction, ( K ) 13 .

Second line

  1. Coupling stiffness of the section for axial stretch–torsion, ( K ) 14 .

  2. Coupling stiffness of the section for axial stretch–bending about the 1-axis, ( K ) 15 .

  3. Coupling stiffness of the section for axial stretch–bending about the 2-axis, ( K ) 16 .

  4. Stiffness of the section for cross-shear, ( K ) 23 .

  5. Coupling stiffness of the section for shear in the first direction–torsion, ( K ) 24 .

  6. Coupling stiffness of the section for shear in the first direction–bending about the 1-axis, ( K ) 25 .

  7. Coupling stiffness of the section for shear in the first direction–bending about the 2-axis, ( K ) 26 .

  8. Coupling stiffness of the section for shear in the second direction–torsion, ( K ) 34 .

Third line

  1. Coupling stiffness of the section for shear in the second direction–bending about the 1-axis, ( K ) 35 .

  2. Coupling stiffness of the section for shear in the second direction–bending about the 2-axis, ( K ) 36 .

  3. Coupling stiffness of the section for torsion–bending about the 1-axis, ( K ) 45 .

  4. Coupling stiffness of the section for torsion–bending about the 2-axis, ( K ) 46 .

  5. Stiffness of the section for cross-bending, ( K ) 56 .