StructuralCurveMember

1D Member (Beam, Column,…)

A general 1D member is defined by its two end-points (or we can say nodes). Therefore, the 1D member position must be specified by two points: first, the starting or begin point and then the end point. A set of properties can also be defined.
Each 1D member has got a unique local co-ordinate system, the origin of which is located in the starting point of a 1D member. The x-axis is always identical with the longitudinal beam axis and its direction is from the starting point towards the end point and is placed to centroid of the cross-section. By default, the y-axis is generally horizontal (unless the beam orientation prevents this) and the z-axis is generally vertical (again, unless the beam orientation in space prevents this configuration). In case of vertical members by default the local y-axis has the same direction as global y-axis.
The local co-ordinate system can be rotated around its x-axis if required.
In addition to this local co-ordinate system, also a principal (or main) co-ordinate system can be referred to on a 1D member. The principal co-ordinate system of a 1D member is related to the principal co-ordinate system of the cross-section of a 1D member.

Specification in the excel

Name of the column header
Type of data
Value example or enum definition
Required value
Description
Name
String
B1
yes
Human readable unique name of the 1D member
Type
String
General
no
The type of the 1D member, used within the analytical model.
E.g. General, Beam, Column, GableColumn, SecondaryColumn, Rafter, Purlin, RoofBracing, WallBracing, Girt, TrussChord, TrussDiagonal, PlateRib, BeamSlab, HollowCoreSlab, CompositePlateRib, CompositeBeamRib
Cross section
String
CS1
yes
The name reference to the existing, valid name of the StructuralCrossSection object
Arbitrary definition
String
AD1
no
The reference to Arbitrary/Tapered/Haunched beam definition StructuralCurveMemberVarying
Nodes
String
N2; N3; N4
yes
All nodes that belong to the curve member and define its geometric shape.
The names of the nodes are separated by ; (semicolon) and space. The order of the nodes has to be from beginning to end.
Segments
String
Line; Circular Arc; Bezier; Parabolic arc; Spline
yes
Defines the shape of the curve between two next nodes. The names are separated by ; (semicolon) and space.
Begin node
String
N1
no
Should be equal to the first node from the Nodes column.
Note that it serves only for viewing SAF file in Excel.
End node
String
N2
no
Should be equal to the last node from the Nodes column.
Note that it serves only for viewing SAF file in Excel.
Internal nodes
String
N77; N78
no
Internal nodes belonging to StructuralCurveMember defined in StructuralPointConnection.
Internal nodes are not geometry defining The names of the nodes are separated by ; (semicolon) and space.
Length [m]
Double
6.425
no
Distance between begin and end node of the curve member.
Geometrical shape
Enum
Line
Circular Arc
Parabolic Arc
Bezier
Spline
Polyline
no
Description of the geometrical type of curve member in general. If the member consists of more than one segments, Geometrical shape is automatically set to Polyline.
LCS
Enum
y by vector
z by vector
y by point
z by point
yes
Local coordinate system. This item specifies the way the local axes of the 1D member are determined. For further understanding see Introduction
LCS Rotation [deg]
Double
45.00
yes
This value defines the rotation of local axes of the 1D member around its x-axis
Coordinate X [m]
Double
0,0
yes
Coordinate of the point or vector defining the LCS in X direction
Coordinate Y [m]
Double
0,1
yes
Coordinate of the point or vector defining the LCS in Y direction
Coordinate Z [m]
Double
0,0
yes
Coordinate of the point or vector defining the LCS in Z direction
System line
Enum
Centre
Top
Bottom
Left
Right
Top left
Top right
Bottom left
Bottom right
yes
The system line is in fact the local x-axis of the member. The attribute of system line applies eccentricities to the member equal to the cross-section dimensions of the member in the specified direction.
Default position of the system line is in the centre of the gravity of the cross-section.
The position of the system line affects results in same way as eccentricities do.
Top - align top surface to center line
Bottom - align bottom surface to center line
Left - align left surface to center line
Right - align right surface to center line
For further explanation see notes below.
Structural Y Eccentricity of Beg Node [mm]
Double
-150
no
Define the position difference between a physical element and its analytical member representation in Y direction (Beg node).
Used to build up physical (structural body from analysis member).
DOES NOT affect internal forces.
Structural Z Eccentricity of Beg Node [mm]
Double
75
no
Define the position difference between a physical element and its analytical member representation in Z direction (Beg node).
Used to build up physical (structural body from analysis member).
DOES NOT affect internal forces.
Structural Y Eccentricity of End Node [mm]
Double
75
no
Define the position difference between a physical element and its analytical member representation in Y direction (End node).
Used to build up physical (structural body from analysis member).
DOES NOT affect internal forces.
Structural Z Eccentricity of End Node [mm]
Double
75
no
Define the position difference between a physical element and its analytical member representation in Z direction (End node).
Used to build up physical (structural body from analysis member).
DOES NOT affect internal forces.
Analysis Y Eccentricity of Beg Node [mm]
Double
75
yes
Define the position difference between a physical element and its analytical member representation in Y direction (Beg node).
Used to build up physical (structural body from analysis member).
DO affects internal forces.
Analysis Z Eccentricity of Beg Node [mm]
Double
75
yes
Define the position difference between a physical element and its analytical member representation in Z direction (Beg node).
Used to build up physical (structural body from analysis member).
DO affects internal forces.
Analysis Y Eccentricity of End Node [mm]
Double
75
yes
Define the position difference between a physical element and its analytical member representation in Y direction (End node).
Used to build up physical (structural body from analysis member).
DO affects internal forces.
Analysis Z Eccentricity of End Node [mm]
Double
75
yes
Define the position difference between a physical element and its analytical member representation in Z direction (End node).
Used to build up physical (structural body from analysis member).
DO affects internal forces.
Layer
String
1st floor
no
Custom created layer.
The layer can thus comprise entities that have something in common (e.g. one floor, columns of one floor, columns of the same length, etc.)
Behaviour in analysis
Enum
Standard
Axial force only
Compression only
Tension only
yes
From the finite element analysis point of view, the 1D member can act like a standard 1D member or like a hinged (pinned) rod. The difference is that the standard 1D member is capable of transferring all the internal forces, while the latter variant only provides for transferring of the axial force.
Color
String
#7FFFFF00
no
Defines colour and transparency of the object. Colour is defined by Hex format #AARRGGBB. Transparency is controlled by the alpha channel AA. If no colour is set then default colour is used.
Parent ID
String
67b35d84-3d04-47aa-aa4a-dc1263982320
no
Is filled for objects created be dividing curved geometry to series of straight line objects. Parent ID will ensure that curved edge is imported as straight parts to nonsupporting application, and back to original supporting application as curved geometry. To ensure successful round trip of segmented objects and their related objects, Parent ID needs to be present in both directions.
Id
String
39f238a5-01d0-45cf-a2eb-958170fd4f39
no
Unique attribute designation

Notes

Complete enumeration of the Formcode, Supported shapes of cross-section and Description ID can be found in chapter Annexes. These properties are set in the object StructuralCrossSection.
Rotation of local co-ordinate system is measured from origin position of local y-axis and the orientation follows positive rotation according to the right-handed rule.
Reference to Alignment enums - examples of alignments.
  • pictures below represents view parallel to direction of center line (LCS respects right hand rule)
An example of use of System line type Bottom right can be seen in the picture below. If the shape of the cross-section is not rectangular then boundary box of the cross-section is considered for position of the system line. The results take in count eccentricities, in example: ey=150 mm, ez=250 mm.
Axis reference is only to illustrate this example, your application can have different cross-section LCS than shown in this example. Alignment of system line should be reflected to your relevant eccentricities based on your cross section LCS.
Last modified 10d ago