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

The starting node of the 1D member.

Has to be specified in the StructuralPointConnection sheet

End node

String

N2

no

The end node of the 1D member.

Has to be specified in the StructuralPointConnection sheet

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.