Navigation:  CADtools > Utilities > GSA Export

 

 

Summary:

Generates GSI and GWA files from 3D lines, polylines, faces and points

 

Description:

If you have created a 3D frame using AutoCAD meshes or by drawing lines or polylines in 3D space, you can use this utility to create a GSA file from it.  The program only recognises 3DFACE, LINE, POLYLINE and POINT objects, so you should first ‘explode’ any meshes to reduce them to 3DFACES.

 

There is also a related command, called OasysAttachSprings, which connects spring nodes (points) to an existing set of 3D faces, either directly or with vertical bar elements, repesented as polylines. If this is required, it should be run before using the GSA Export function.

 

After selecting the objects to process and the filename for the output, there are options regarding node-numbering. The default is to have the nodes numbered ‘sequentially’: 1, 2, 3, etc. The numbers will correspond to the order that the relevant entities were drawn in AutoCAD. The other option is to construct a ‘user’ numbering system. This lets the user specify ‘bands’ of y- and z-coordinates, and the nodes will be numbered in order of x-values within each band. The number increments between each band are also specified. The idea behind this is to highlight linkages between elements. If the ‘Attach springs’ routine has been used, it will be clear to see that each spring node is linked to the node above it. In this case the two nodes will differ by the z-increment, as specified by the user. Finally, the user can also specify a new UCS for the numbering system.

 

Command: OasysAttachSprings

Select objects: Pick set of 3D faces

Attach vertical bars to nodes? [Yes/No] <Yes>: Type Y or N

 

Command: OasysGSAOut

Converts 3DFACE, LINE, POLYLINE and POINT objects, all others are ignored.

Pick object(s) to process : Select objects

File type [Gsi/gWa] <Gsi> : Select type of output

Select GSA file: Give filename for output file

 

Use sequential node-numbering or user? [Sequential/User] <Sequential>: User

Use current UCS or define? [Current/Define] <Current>: Define

Pick origin:

Pick point on positive x-axis:

Pick point on positive x-y plane:

Enter number for 1st node: 1

Enter node number increment in x-direction: 1

Enter distance between rows (y): Type or pick distance

Enter node number increment in y-direction: 10

Enter distance between planes (z): Type or pick distance

Enter node number increment in z-direction: 100

 

Mapping Table:

 

 

Note: The program will set the export units to the units currently defined via CADtools. If the units have not been set in the drawing, millimetres (mm) are assumed.

 

Exported GSI files may also be used by the load areas calculator, see GSA Area Calculator for more details.

 

 

 

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