SECTION

Bulk Data Entry

SECTION – Cross-section of the Model

Description

Defines a specific face of a cross-section of the model. The section is determined through a set of Grid points and the particular face is specified by a set of elements. The face is interpreted as the side of the Grid point set not containing the specified elements.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
SECTION	SID	LABEL	GSID	ESID	RSID	CID	GID

Field	Contents
SID	Set identification number of the section. No default (Integer)
LABEL	The section name associated with the defined section. No default (Character string)
GSID	Set identification number of a SET of GRID points that defines the geometry of the section (see comment 2). No default (Integer > 0)
ESID	Set identification number of a SET of elements (TYPE=ELEM) that defines the face of the section (see comment 2). No default (Integer > 0)
RSID	Set identification number of a SET of rigid elements (TYPE=RIGID) that defines the face of the section (see comment 2). No default (Integer > 0)
CID	Coordinate system identification number of the coordinate system into which the forces and moments are resolved. Default = 0 (Integer ≥ 0)
GID	Grid point identification number of the grid about which the moments are calculated. Default = <Geometric Centroid of the Section> (Integer > 0)

Comments

The SECTION entry can be used to define a face of the cross-section on which the forces/moments are calculated as a response in optimization runs via RTYPE=RESFORCE (on the DRESP1 entry). In such cases, Grid Point Forces or Moments are added at each GRID specified within the grid set (GSID). The effect of all elements on the grid points (GSID) is considered in the calculation of the response except the elements specified via ESID.

2.	The section is determined through a set of grid points and the particular face is specified by a set of elements. The face is interpreted as the side of the grid point set NOT containing the specified elements (see Figures 1 through 3). This is similarly applicable to RSID (rigid element set).

section_resforce

Figure 1: Defining the SECTION for the RESFORCE response

section_gsid

Figure 2: Selecting the GSID set

section_esid

Figure 3: Selecting the corresponding ESID

3.	The default GID is the geometric center of the cross-section. For example, in a shell model, if the cross-section is tapered (Figure 4), the geometric center is automatically updated (if the GID field is blank).

section_geometric_center

Figure 4: Geometric center via GID=Default