18.7.2 General surface element library

Products: ABAQUS/Standard  ABAQUS/Explicit  ABAQUS/CAE  

References

Element types

SFM3D33-node triangle
SFM3D4(S)    4-node quadrilateral
SFM3D4R4-node quadrilateral, reduced integration
SFM3D6(S)    6-node triangle
SFM3D8(S)    8-node quadrilateral
SFM3D8R(S)    8-node quadrilateral, reduced integration

Active degrees of freedom

1, 2, 3

Additional solution variables

None.

Nodal coordinates required

, ,

Element property definition

Input File Usage:           Use the following option to define surface element properties:
 
*SURFACE SECTION

If rebar are being defined, use the following option in conjunction with the *SURFACE SECTION option:

 *REBAR LAYER

Use the following option to define a mass density per unit area:

*SURFACE SECTION, DENSITY=number

ABAQUS/CAE Usage: 

Property module: Create Section: select Shell as the section Category and Surface as the section Type, Rebar Layers (optional)

You cannot define the mass per unit area for a surface section in ABAQUS/CAE.

Element-based loading

Distributed loads

Distributed loads are specified as described in Distributed loads, Section 19.4.3. Gravity, centrifugal, rotary acceleration, and Coriolis force loads apply only if the surface elements have rebar defined or if the elements have a defined density.


Load ID (*DLOAD):  BX

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Body force in the global -direction.


Load ID (*DLOAD):  BY

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Body force in the global -direction.


Load ID (*DLOAD):  BZ

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Body force in the global -direction.


Load ID (*DLOAD):  BXNU

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Nonuniform body force in the global -direction with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (DLOAD, Section 25.2.5) and VDLOAD in ABAQUS/Explicit (VDLOAD, Section 25.3.1).


Load ID (*DLOAD):  BYNU

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Nonuniform body force in the global -direction with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (DLOAD, Section 25.2.5) and VDLOAD in ABAQUS/Explicit (VDLOAD, Section 25.3.1).


Load ID (*DLOAD):  BZNU

ABAQUS/CAE Load/Interaction:  Body force

Units:  FL–3

Description:  Nonuniform body force in the global -direction with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (DLOAD, Section 25.2.5) and VDLOAD in ABAQUS/Explicit (VDLOAD, Section 25.3.1).


Load ID (*DLOAD):  CENT(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–4 (ML–3T–2)

Description:  Centrifugal load (magnitude is input as , where is the mass density per unit volume, is the angular speed).


Load ID (*DLOAD):  CENTRIF(S)

ABAQUS/CAE Load/Interaction:  Rotational body force

Units:  T–2

Description:  Centrifugal load (magnitude is input as , where is the angular speed).


Load ID (*DLOAD):  CORIO(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–4T (ML–3T–1)

Description:  Coriolis force (magnitude is input as , where is the mass density per unit volume, is the angular speed). The load stiffness due to Coriolis loading is not accounted for in direct steady-state dynamics analysis.


Load ID (*DLOAD):  GRAV

ABAQUS/CAE Load/Interaction:  Gravity

Units:  LT–2

Description:  Gravity loading in a specified direction (magnitude is input as acceleration).


Load ID (*DLOAD):  HP(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Hydrostatic pressure applied to the element reference surface and linear in global . The pressure is positive in the direction of the positive element normal.


Load ID (*DLOAD):  P

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Pressure applied to the element reference surface. The pressure is positive in the direction of the positive element normal.


Load ID (*DLOAD):  PNU

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Nonuniform pressure applied to the element reference surface with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (DLOAD, Section 25.2.5) and VDLOAD in ABAQUS/Explicit (VDLOAD, Section 25.3.1). The pressure is positive in the direction of the positive element normal.


Load ID (*DLOAD):  ROTA(S)

ABAQUS/CAE Load/Interaction:  Rotational body force

Units:  T–2

Description:  Rotary acceleration load (magnitude is input as , where is the rotary acceleration).


Load ID (*DLOAD):  TRSHR

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Shear traction on the element reference surface.


Load ID (*DLOAD):  TRSHRNU(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Nonuniform shear traction on the element reference surface with magnitude and direction supplied via user subroutine UTRACLOAD (UTRACLOAD, Section 25.2.41).


Load ID (*DLOAD):  TRVEC

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  General traction on the element reference surface.


Load ID (*DLOAD):  TRVECNU(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Nonuniform general traction on the element reference surface with magnitude and direction supplied via user subroutine UTRACLOAD (UTRACLOAD, Section 25.2.41).


Load ID (*DLOAD):  VP(E)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–3T

Description:  Viscous surface pressure applied to the element reference surface. The pressure is proportional to the velocity normal to the element face and opposing the motion.

Foundations

Foundations are available only in ABAQUS/Standard and are specified as described in Element foundations, Section 2.2.2.


Load ID (*FOUNDATION):  F

ABAQUS/CAE Load/Interaction:  Elastic foundation

Units:  FL–3

Description:  Elastic foundation.

Surface-based loading

Distributed loads

Surface-based distributed loads are specified as described in Distributed loads, Section 19.4.3.


Load ID (*DSLOAD):  HP(S)

ABAQUS/CAE Load/Interaction:  Pressure

Units:  FL–2

Description:  Hydrostatic pressure on the element reference surface and linear in global . The pressure is positive in the direction opposite to the surface normal.


Load ID (*DSLOAD):  P

ABAQUS/CAE Load/Interaction:  Pressure

Units:  FL–2

Description:  Pressure on the element reference surface. The pressure is positive in the direction opposite to the surface normal.


Load ID (*DSLOAD):  PNU

ABAQUS/CAE Load/Interaction:  Pressure

Units:  FL–2

Description:  Nonuniform pressure on the element reference surface with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (DLOAD, Section 25.2.5) and VDLOAD in ABAQUS/Explicit (VDLOAD, Section 25.3.1). The pressure is positive in the direction opposite to the surface normal.


Load ID (*DSLOAD):  TRSHR

ABAQUS/CAE Load/Interaction:  Surface traction

Units:  FL–2

Description:  Shear traction on the element reference surface.


Load ID (*DSLOAD):  TRSHRNU(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Nonuniform shear traction on the element reference surface with magnitude and direction supplied via user subroutine UTRACLOAD (UTRACLOAD, Section 25.2.41).


Load ID (*DSLOAD):  TRVEC

ABAQUS/CAE Load/Interaction:  Surface traction

Units:  FL–2

Description:  General traction on the element reference surface.


Load ID (*DSLOAD):  TRVECNU(S)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–2

Description:  Nonuniform general traction on the element reference surface with magnitude and direction supplied via user subroutine UTRACLOAD (UTRACLOAD, Section 25.2.41).


Load ID (*DSLOAD):  VP(E)

ABAQUS/CAE Load/Interaction:  Not supported

Units:  FL–3T

Description:  Viscous surface pressure applied to the element reference surface. The pressure is proportional to the velocity normal to the element surface and opposing the motion.

Incident wave loading

Surface-based incident wave loading is also available for these elements. See Acoustic loads, Section 19.4.5.

Element output

Output is currently available only when the surface element is used to carry rebar layers. See Defining reinforcement, Section 2.2.3, for details.

Node ordering on elements

Numbering of integration points for output