Products: ABAQUS/Standard ABAQUS/Explicit ABAQUS/CAE
| Input File Usage: | Use either of the following options: |
*SHELL SECTION *SHELL GENERAL SECTION |
| ABAQUS/CAE Usage: | Property module: Create Section: select Shell as the section Category and Homogeneous or Composite as the section Type |
Distributed loads are specified as described in “Distributed loads,” Section 19.4.3.
Load ID (*DLOAD): BX
ABAQUS/CAE Load/Interaction: Body force
Units: FL–3
Description: Body force (give magnitude as force per unit volume) in the global 
-direction.
Load ID (*DLOAD): BY
ABAQUS/CAE Load/Interaction: Body force
Units: FL–3
Description: Body force (give magnitude as force per unit volume) in the global 
-direction.
Load ID (*DLOAD): BZ
ABAQUS/CAE Load/Interaction: Body force
Units: FL–3
Description: Body force (give magnitude as force per unit volume) in the global 
-direction.
Load ID (*DLOAD): BXNU
ABAQUS/CAE Load/Interaction: Body force
Units: FL–3
Description: Nonuniform body force (give magnitude as force per unit volume) 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 (give magnitude as force per unit volume) in the global -direction, with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (“DLOAD,” Section 25.2.5) and VDLOAD (“VDLOAD,” Section 25.3.1) in ABAQUS/Explicit.
Load ID (*DLOAD): BZNU
ABAQUS/CAE Load/Interaction: Body force
Units: FL–3
Description: Nonuniform body force (give magnitude as force per unit volume) in the global -direction, with magnitude supplied via user subroutine DLOAD in ABAQUS/Standard (“DLOAD,” Section 25.2.5) and VDLOAD (“VDLOAD,” Section 25.3.1) in ABAQUS/Explicit.
Load ID (*DLOAD): CENT(S)
ABAQUS/CAE Load/Interaction: Not supported
Units: FL–4 (ML–3T–2)
Description: Centrifugal load (magnitude defined as 
, where 
is the mass density and 
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 input 
, where is the mass density and 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): HPn(S)
ABAQUS/CAE Load/Interaction: Not supported
Units: FL–2
Description: Hydrostatic pressure on face n, linear in global . A positive pressure is directed into the element.
Load ID (*DLOAD): Pn
ABAQUS/CAE Load/Interaction: Not supported
Units: FL–2
Description: Pressure on face n. A positive pressure is directed into the element.
Load ID (*DLOAD): PnNU
ABAQUS/CAE Load/Interaction: Not supported
Units: FL–2
Description: Nonuniform pressure on face n 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). A positive pressure is directed into the element.
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): VPn(E)
ABAQUS/CAE Load/Interaction: Not supported
Units: FL3T
Description: Viscous pressure on face n, applying a pressure proportional to the velocity normal to the face and opposing the motion.
Foundations are specified as described in “Element foundations,” Section 2.2.2.
Load ID (*FOUNDATION): Fn(S)
ABAQUS/CAE Load/Interaction: Elastic foundation
Units: FL–3
Description: Elastic foundation on face n. A positive pressure is directed into the element.
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 applied to the element surface, 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 applied to the element 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 applied to the element 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: FL3T
Description: Viscous surface pressure. The viscous pressure is proportional to the velocity normal to the element face and opposing the motion.
If a local coordinate system is not assigned to the element, the stress/strain components, as well as the section forces/strains, are in the default directions on the surface defined by the convention given in “Conventions,” Section 1.2.2. If a local coordinate system is assigned to the element through either the section definition (“Orientations,” Section 2.2.5) or an element property assignment (“Assigning element properties on an element-by-element basis,” Section 13.1.5), the stress/strain components and the section forces/strains are in the surface directions defined by the local coordinate system.
The local directions defined in the reference configuration are rotated into the current configuration by the average material rotation.
Stress and other tensors (including strain tensors) are available. All tensors have the same components. For example, the stress components are as follows:
S11 | Local |
S22 | Local |
S12 | Local |
The stress in the thickness direction, 
, is reported as zero to the output database as discussed in “ABAQUS/Standard output variable identifiers,” Section 4.2.1. may be obtained through the average section stress variable SSAVG6.
SF1 | Direct membrane force per unit width in local 1-direction. |
SF2 | Direct membrane force per unit width in local 2-direction. |
SF3 | Shear membrane force per unit width in local 1–2 plane. |
SF4 | Transverse shear force per unit width in local 1-direction. |
SF5 | Transverse shear force per unit width in local 2-direction. |
SF6 | Thickness stress integrated over the element thickness. |
SM1 | Bending moment force per unit width about local 1-axis. |
SM2 | Bending moment force per unit width about local 2-axis. |
SM3 | Twisting moment force per unit width in local 1–2 plane. |
The section force and moment resultants per unit length in the normal basis directions in a given shell section of thickness 
can be defined on this basis as
is constant through the thickness.
SSAVG1 | Average membrane stress in local 1-direction. |
SSAVG2 | Average membrane stress in local 2-direction. |
SSAVG3 | Average membrane stress in local 1–2 plane. |
SSAVG4 | Average transverse shear stress in local 1-direction. |
SSAVG5 | Average transverse shear stress in local 2-direction. |
SSAVG6 | Average thickness stress in the local 3-direction. |
The average section stresses are defined as
and is the current section thickness. is constant through the thickness.SE1 | Direct membrane strain in local 1-direction. |
SE2 | Direct membrane strain in local 2-direction. |
SE3 | Shear membrane strain in local 1–2 plane. |
SE4 | Transverse shear strain in the local 1-direction. |
SE5 | Transverse shear strain in the local 2-direction. |
SE6 | Strain in the thickness direction. |
SK1 | Curvature change about local 1-axis. |
SK2 | Curvature change about local 2-axis. |
SK3 | Surface twist in local 1–2 plane. |
The local directions are defined in “Shell elements: overview,” Section 15.6.1.
STH | Section thickness, which is the current section thickness if geometric nonlinearity is considered; otherwise, it is the initial section thickness. |
TSHR13 | 13-component of transverse shear stress. |
TSHR23 | 23-component of transverse shear stress. |
Estimates of the transverse shear stresses are available at section integration points as output variables TSHR13 or TSHR23 for both Simpson's rule and Gauss quadrature. For Simpson's rule output of variables TSHR13 or TSHR23 should be requested at nondefault section points, since the default output is at section point 1 of the shell section where the transverse shear stresses vanish.
For numerically integrated sections, estimates of the interlaminar shear stresses in composite sections—i.e., the transverse shear stresses at the interface between two composite layers—can be obtained only by using Simpson's rule. With Gauss quadrature no section integration point exists at the interface between composite layers.
Unlike the S11, S22, and S12 in-surface stress components, TSHR13 and TSHR23 are not calculated from the constitutive behavior at points through the shell section. They are estimated by matching the elastic strain energy associated with shear deformation of the shell section with that based on piecewise quadratic variation of the transverse shear stress across the section, under conditions of bending about one axis (see “Transverse shear stiffness in composite shells and offsets from the midsurface,” Section 3.6.8 of the ABAQUS Theory Manual). Therefore, interlaminar shear stress calculation is supported only when the elastic material model is used for each layer of the shell section. If you specify the transverse shear stiffness values, interlaminar shear stress output is not available. TSHR13 and TSHR23 are valid only for sections that have one element through the thickness direction. For sections with two or more continuum shell elements stacked in the thickness direction, output variables SSAVG4 and SSAVG5 should be used instead.
direct stress.
direct stress.
shear stress.
