SECOFFSET
SECOFFSET, Location, OFFSET1, OFFSET2, CG-Y, CG-Z, SH-Y, SH-Z
Defines the section offset for cross sections.
Location,OFFSET1,OFFSET2,CG-Y,CG-Z,SH-Y,SH-ZThe location of the nodes in the section. All are dependent on the type. See the "Notes" section for information about the values for the various section types.
Notes
The SECOFFSET command is divided into four types: Beams, Pipes, Shells, and Preintegrated General Shells.
The offsets defined by the SECOFFSET command are associated with the section most recently defined using the SECTYPE command. Not all SECOFFSET location values are valid for each subtype.
For the thermal shell elements, SHELL131 and SHELL132, the node offset specified by SECOFFSET is used in thermal contact analyses. Otherwise, the SECOFFSET command has no effect on the solution for these elements and is used only for visualization purposes.
This command is not valid with thermal solid elements SOLID278 and SOLID279.
For beam elements BEAM188/BEAM189 and pipe elements PIPE288/PIPE289 in the XY plane, an offset is not allowed if it causes the elements to be nonsymmetric about the XY plane.
Beams
Type: BEAM
Argument data to provide:
Location, OFFSETY, OFFSETZ, CG-Y, CG-Z, SH-Y, SH-Z
Location- CENT --
Beam node will be offset to centroid (default).
- SHRC --
Beam node will be offset to shear center.
- ORIGIN --
Beam node will be offset to origin of the cross section.
- USER --
Beam node will be offset to the location specified by
OFFSETYandOFFSETZ.
OFFSETY,OFFSETZValues that locate the node with respect to the default origin of the cross section when the
Locationargument is set to USER. Valid only when USER is set.The following figure illustrates the offsets for a channel cross section, and shows the relative locations of SHRC and CENT.
CG-Y,CG-Z,SH-Y,SH-ZOverride the program-calculated centroid and shear centroid locations.
Note: This option should only be used by advanced users modeling composite cross sections.
Pipes
Type: PIPE
Argument data to provide:
OFFSETY, OFFSETZ
OFFSETY,OFFSETZValues that locate the node with respect to the center of the pipe.
Shells
Type: SHELL
Argument data to provide:
Location, OFFSET
Location- TOP --
Shell node will be offset to top of the section.
- MID --
Shell node will be offset to midplane of the section (default).
- BOT --
Shell node will be offset to bottom of the section.
- USER --
Shell node will be offset to the location specified by
OFFSET.
OFFSETValue that locates the node with respect to the default origin (midplane) of the section. Valid only when
Location= USER.The offset alters only the reference surface of the shell elements (that is, where the nodes are located). It does not change the physical dimensions of the shell itself; the volume and mass remain constant when an offset is specified.
Preintegrated General Shells
Type: GENS
Argument data to provide:
Location, OFFSET
Location- MID --
Shell node will be offset to midplane of the section (default).
- USER --
Shell node will be offset to the location specified by
OFFSET.
OFFSETValue that locates the node with respect to the default origin (midplane) of the section. Valid only when
Location= USER.The offset alters only the reference surface of the shell elements (that is, where the nodes are located).