2.17 Overview of International Law on Organ Trafficking
2.17.4 Regional responses to organ trafficking
Complete structural models can be imported into SPACE GASS or exported to other
programs using the very comprehensive CIMSteel/2 (CIS/2) Step, IFC Step or Revit Structure transfer options. Each of these formats can contain the complete structural model, including loads and design data.
They can be used to link SPACE GASS with programs such as Tekla Structures (XSteel), ProSteel, Microstation, Frameworks Plus, StruCAD, Revit Structure, Bentley Structural, AutoCAD and many others that use the CIMSteel/2 (CIS/2) Step or IFC Step formats.
Revit Structure is slightly different to the other programs because in addition to
communicating with SPACE GASS via the CIMSteel/2 or IFC links, it can also communicate via special import and export menu items that can be added to the Revit Structure "Tools"
menu.
The physical and analytical models
The "physical" model includes all of the "visible" information such as the geometry of the beams, columns, braces, cables, trusses, struts, ties, walls, slabs and connections. It includes all the components that make up the model’s physical attributes.
The "analytical" model includes the "visible" information too, but it also contains "hidden"
information such as support conditions, member end releases, offset data, section and material properties, loads, load combinations, design data and analysis results.
The other main difference with the analytical model is that, depending on the program you are importing from, the geometry may be somewhat idealised so that the centroids of members line up with the members they are connected to. For example, bracing members that connect to a beam-column connection do not often line up with the centroid of the beam-column connection in the real structure and in the "physical" model, however they may be adjusted to line up in the "analytical" model.
Section name conversion files
One of the major obstacles to successfully transferring data between programs is that there is no standard naming convention for section property names and hence every program uses slightly different names. To solve this problem, conversion files are used to convert the section names used by SPACE GASS to the names used by other programs. Conversion files are supplied with SPACE GASS for converting section names to Tekla Structures, Prosteel, Revit Structure and others. You can also make your own section name conversion files quite easily.
Standard section name conversion files are supplied with SPACE GASS for each of the SPACE GASS section libraries and each of the well-known programs that you may want SPACE GASS to communicate with. For example, Tekla Structures conversion files are supplied for each of the SPACE GASS section libraries. Similar sets of conversion files are also supplied for Revit Structure, Prosteel, etc.
Creating custom section name conversion files
You must first initiate a CIS/2 or IFC import or export from the File menu to display the following form.
Custom section name conversion files can then be created in either of two ways.
1. You can create a custom conversion file that is a combination of some of the standard conversion files supplied with SPACE GASS.
To do this you must first select a program name in the "Convert section names for" list box and then click the "Libraries" branch of the menu tree on the left and ensure that the SPACE GASS libraries from which the sections will be taken are listed in the "Library search order"
box.
You can then create the custom conversion file by clicking the "Create a custom section name conversion file" button.
2. You can create a template for a custom conversion file that contains just the SPACE GASS section names and the libraries they come from, but not the "other program" names.
To do this you must click the "Libraries" branch of the menu tree on the left and then ensure that the SPACE GASS libraries from which the sections will be taken are listed in the "Library search order" box.
just one cell.
Section name conversion files are stored in the SPACE GASS program folder (usually
"c:\Program files\SPACE GASS\Exe").
Details of how to import and export using these links are explained in the following sections.
Import links
You can import a CIS/2 or IFC Step file by selecting "Import - from CIMSteel/2 Step" or
"Import - from IFC Step" from the File menu.
When importing from Revit Structure, you can import a CIS/2 or IFC Step file created by it or you can select the "Send Model to SPACE GASS" item from the Revit Structure "Tools >
External Tools" menu as explained in "Special Revit Structure Links".
Even though the internal structure of CIS/2 step files and IFC step files are quite different, the importing procedure is the same and hence the following instructions apply to both.
The name of the file being imported is displayed in the "Data Filename" field and you can select another file by clicking on the button to the right of the input field.
When importing, to ensure that the section names used by the source program are converted properly to SPACE GASS names, you should do the following:
1. If you are linking with a standard program for which a section name conversion file exists, select it in the "Convert section names for" list box.
If the name of the program you are linking with does not appear in the list, it simply means that there is currently no standard conversion file for that program. If so, you should select
"Other". You can then create and use a custom conversion file or use one that you previously created as explained in "Creating custom section name conversion files" in the previous section. Alternatively, you can just skip the custom conversion file option and the section names will be imported or exported with no conversion.
2. Click the "Libraries" branch of the menu tree on the left to display the section libraries form as
If you selected a program name in the "Convert section names for" list box in step 1 above, ensure that the "Use a standard section name conversion file" option is ticked. This will activate the section name conversion using the standard conversion files supplied with SPACE GASS.
If you selected "Other" in the "Convert section names for" list box in step 1 above, and you have a custom conversion file that you want to use, ensure that the "Use a custom section name conversion file" option is ticked and that the name of the custom conversion file is in the
"Conversion filename" field. If you wish to create a custom conversion file, follow the procedure in "Creating custom section name conversion files" in the previous section.
If you wish to use a mixture of custom and standard conversion files, you can tick both the
"Use a custom section name conversion file" and "Use a standard section name conversion file" options. In this case, SPACE GASS will try to convert the section name using the custom conversion file first and, if the name can’t be found there, the standard conversion files will be used.
3. You also need to check that the appropriate SPACE GASS libraries are listed in the "Library search order" box.
The "Library search order" box controls which SPACE GASS libraries will be used when the section names being imported are converted. If the name of a section being imported does not appear in one of the libraries listed in this box then it will not be converted. It is therefore important that you include enough libraries in the "Library search order" box to ensure that all the sections being imported have their names converted.
You can include all libraries in the box, however this may slow down the import process
You can specify the starting node number or, if you leave it at zero, the imported nodes will be automatically numbered starting from the first available number.
Nodes that are very close together can be merged into one, and the connecting members and plates adjusted to suit.
If you select the "Adjust lower limits of node coordinates by" checkbox, SPACE GASS will find the node with the lowest coordinates and move it to the coordinates that you specify. The rest of the model will also be moved by the same amount.
You can specify the starting member and plate numbers or, if you leave them at zero, the imported members and plates will be automatically numbered starting from the first available
A number of programs that generate CIS/2 and IFC Step files incorrectly mix radians and degrees when specifying member direction angles. If you are importing one of these non-standard files and find that some members are rotated incorrectly, you can select the "Assume radians for all angular measurements" checkbox to correct the problem.
For more information about the "Physical" and "Analytical" models, refer to "The physical and analytical models" in the previous section.
Export links
You can export a CIS/2 or IFC Step file by selecting "Export - to CIMSteel/2 Step" or
"Export - to IFC Step" from the File menu.
When exporting to Revit Structure, you can export a CIS/2 or IFC Step file or you can select the "Update Model from SPACE GASS" item from the Revit Structure "Tools > External Tools" menu as explained in "Special Revit Structure Links".
Even though the internal structure of CIS/2 step files and IFC step files are quite different, the exporting procedure is the same and hence the following instructions apply to both.
The name of the file being exported to is displayed in the "Data Filename" field and you can select another file by clicking on the button to the right of the input field.
When exporting, to ensure that the section names used by SPACE GASS are converted properly to the names used by the destination program, you should do the following:
1. If you are linking with a standard program for which a section name conversion file exists, select it in the "Convert section names for" list box.
If the name of the program you are linking with does not appear in the list, it simply means that there is currently no standard conversion file for that program. If so, you should select
"Other". You can then create and use a custom conversion file or use one that you previously created as explained in "Creating custom section name conversion files" in the previous section. Alternatively, you can just skip the custom conversion file option and the section names will be imported or exported with no conversion.
2. Click the "Libraries" branch of the menu tree on the left to display the section libraries form as
If you selected a program name in the "Convert section names for" list box in step 1 above, ensure that the "Use a standard section name conversion file" option is ticked. This will activate the section name conversion using the standard conversion files supplied with SPACE GASS.
If you selected "Other" in the "Convert section names for" list box in step 1 above, and you have a custom conversion file that you want to use, ensure that the "Use a custom section name conversion file" option is ticked and that the name of the custom conversion file is in the
"Conversion filename" field. If you wish to create a custom conversion file, follow the procedure in "Creating custom section name conversion files" in the previous section.
If you wish to use a mixture of custom and standard conversion files, you can tick both the
"Use a custom section name conversion file" and "Use a standard section name conversion file" options. In this case, SPACE GASS will try to convert the section name using the custom conversion file first and, if the name can’t be found there, the standard conversion files will be used.
You can choose which components of the model to export by clicking the "Export" branch of the menu tree on the left.
The normal procedure is to export the analytical model because, as well as the geometric information, it contains "hidden" information such as support conditions, member end releases, offset data, section and material properties, loads, load combinations, design data and analysis results. However, if you are exporting to a program that requires the physical model then you should select it. Note that when exporting from SPACE GASS, the geometric information in the physical and analytical models is the same.
For more information about the "Physical" and "Analytical" models, refer to "The physical and analytical models" in the previous section.
Special Revit Structure links
Revit Structure is slightly different to the other programs because there are two ways to link it to SPACE GASS. In addition to being able to communicate with SPACE GASS via the CIMSteel/2 and IFC Step file links, Revit Structure can be configured to create SPACE GASS jobs directly and also update the Revit model from them.
The advantage of using the direct Revit Structure link over the CIMSteel/2 and IFC links is that after you have transferred the model to SPACE GASS, you can import the section property and steel design changes back into Revit Structure without completely replacing the Revit Structure model.
The advantage of the CIMSteel/2 and IFC Step file links is that you can start with a SPACE GASS model and transfer it into Revit Structure to create a Revit model from scratch. You can’t do this with the direct Revit Structure link.
Of course, you can use a combination of methods. You could start with a SPACE GASS model, export it using CIMSteel/2 or IFC to create a new Revit Structure model, add to the model in Revit Structure and then export it back to SPACE GASS using the direct Revit Structure link.
Setting up the direct link between SPACE GASS and Revit Structure
You can add the special SPACE GASS items to the Revit Structure "Tools" menu by running the RevitSpaceGassLink.exe file in the SPACE GASS program folder (usually "c:\Program files\SPACE GASS\Exe").
The program will attempt to find the SPACE GASS and Revit Structure program folders and then display them in the following form.
If either field doesn’t display a folder name with "(file found)" at the end, you will have to click the appropriate browse button at the right of the field to select the program folder
When exporting to SPACE GASS, you have full control over units, connections between beams and columns, loads, member offsets, specification of tension-only members, section names, etc.
If the names of sections in your Revit Structure model are different to the names used in the SPACE GASS section libraries, you can use (or set up your own) section name conversion file that converts the Revit Structure names to the SPACE GASS names. For more
information, refer to "Creating custom section name conversion files" in "CIMSteel/2 Step, IFC Step and Revit links".
Transferring to Revit Structure
When the SPACE GASS analysis and/or design is complete, you can update the Revit Structure model by clicking the "Update Model from SPACE GASS" item from the Revit Structure "Tools" menu.
When importing from SPACE GASS you can elect to incorporate steel design data into the Revit Structure model. This is then retained in Revit Structure and returned to SPACE GASS the next time you export a model to SPACE GASS from Revit Structure.