RAM - Revit Link v4 eSeminar
| AppliesTo | |||
| Product(s): | RAMRevitLink | ||
| Version(s): | ALL | ||
| Environment: | N/A | ||
| Area: | Import/Export | ||
| Subarea: | |||
| OriginalAuthor: | BentleyTechnicalSupportGroup | ||
Q&AandLinktoSeminarRecording
This eSeminar was orginally presented on 28 February, 2012. You can view the recording online at our Be Connected site.
The following are the product-related questions and corresponding answers from the eSeminar presented on 28th February 2012.
Q: Can this Revit link enable users to bring in "multiple Ram Models" into the same "single" Revit Model?
A: No. Only one RAM Structural System model can be imported into a Revit file. However, you can use linking between multiple Revit files to associate various structures in a single Revit project.
Q: What is the Full form of ISM?
A: Bentley's Integrated Structural Modeling technology utilizes the MicroStation .dgn file format to create a repository of structural data common among various structural programs. The structural data is a subset of the complete BIM and any one ISM Enabled client application can utilize a subset of the structural data from the ISM repository. Further, this provides design history which allows rolling back to previous version as well as merging versions of repository content. The free Structural Synchronizer program is used to manage ISM repositories and sync structural data with client applications. A free ISM Revit plug-in is also available to exchange structural data with a Revit project.
Q: What are the possibilities with using RAM elements and Revit structure?
A: RAM Elements is an ISM Enabled program and is fully compliant with the ISM v2.1 standard. You can exchange structural data with RAM Elements through the ISM Revit plug-in.
Q: is it true you can only set the "offset" coordinates once? Otherwise you lose the RAM/Revit link?
(Note: There were several questions on this same topic.)
A: When you set coordinates on the Offset tab of the settings dialog, that value becomes a read-only property of the RAM model. We do have a spreadsheet that can be used to create a new RAM model at a zero origin in RAM. If there have been loads or foundations added to the model, they are lost when you create the new model.
Q: When I am using the RAM Revit Link it appears that the link reads the reference level on a beam, and not the analytical model assignment, is there any way to make the RAM Revit Link read the analytical model in Revit 2012?
A: The link is only going to transfer data from the analytical model. It’s likely that there have been changes made which have unintended consequences in the analytical model. You should use the analytical adjust tools to make modifications, similar to those made I the demo for the shortened column.
Q: Why isn't the slab on top of the beams? Was this intentional?
A: Yes, this was intentional, but will be enhanced in future versions. During portions of the live demo, the display of the Revit floor was toggled off in the {3D} view of the physical model.
Q: You should model a cantilever at one of the joists too, not just at columns.
A: Cantilevers on beams that are supported by girders are handled by the link, but not demonstrated in this eSeminar. Cantilevers for joists and concrete beams are not supported.
Q: What about when the actual column splice is 4 feet above the floor?
(Note: There were several questions on this same topic.)
A: You can use the same column shorten/extend method in the physical model as shown in the demo for extending a beam cantilever. Just be certain to adjust the analytical model so it actually changes sections at the floor level, in the plane collinear with the floor framing analytical members.
Q: Can you specify the column splice location in RAM?
A: No. The splice assignment in RAM Steel Column is used to indicate that the program may assign a different section size on the adjacent story above. The exact splice location is not specified with RAM because it isn't used in RAM. The link will respect a story level that is set in RAM but it will be at the story level when imported into Revit.
Q: When exporting a Revit model into RAM, how does RAM treat members that it can't analyze, i.e. curved members, etc.?
A: The link only passes data which the RAM Structural System can analyze. Any such members will not be exported to RAM via the link.
Q: How well does custom/other framing translate between RAM and Revit, such as LVL /wood framing?
A: The “other” material now transfers to RAM via the link. You will probably need to specify the material as “generic” in Revit, first.
Q: How often are the RAM - Revit links updated?
A: Patch updates are issued as needed, but relatively often (roughly monthly). Larger, feature updates are less often.
Q: Is there an efficient way to model open web steel joists so they show up with the seats in the correct location above the supporting member in Revit, but no have to make substantial modifications to your analytical model so that Ram SS will function correctly?
A: It is best to specify the joist seat offsets when a joist is added to the Revit model. Otherwise, joist offsets are subject to the same analytical/physical modeling differences in Revit as demonstrated with column end offsets.
Q: In an integrated practice, is it better to start a model in Revit or RAM?
A: We see users who start in either, though it appears to be most common to start in Revit (perhaps as models are received from clients).
Q: Can you expand on the differences between the RAM-Revit link versus the ISM-Revit link?
A: The Revit link uses the analytical model and ISM uses the physical model to exchange the location of the elements. Not all material is available in the ISM plug-in yet and some elements will be assigned a generic ISM material. Not all deck types are available and one of the ones that is available needs to be used to export decks from RAM. RAM does not support importing decks in this version. It will import decks in the next release. A significant update to the RAM-ISM-Revit link is currently being developed and will be released this summer.
Q: We are experiencing trouble with exporting Revit Braces to RAM. Any tips for successfully modeling those in Revit and get them to RAM?
A: Yes. You can read some tips in our [[RAM Revit Link Best Practices]] wiki topic. However, you should make sure that the reference levels are set to the top framing level for the brace. Also, make sure to review the analytical model in Revit in order to ensure that the braces are appropriately connected to the framing members and/or columns.
Q: We have practiced with a multi-story building and slab on grade, of which we exported from Revit to RAM Steel. After working in RAM Steel and importing back to Revit, the ground floor slab on grade information is lost.
A: This is a limitation of the Revit API, which does not allow for the import of continuous or mat foundations.
Q: If you start with Revit, send to RAM and bringing back to Revit, how do you avoid duplication of levels?
A: Make sure that the Import as New Model option is not set during re-import. This option will result in duplicate levels when importing back into a Revit project.
Q: You modeled the cant. by shortening the column. How would you handle a baseplate that would be added in Revit? How will that impact the RSS model?
A: You can make an analytical model adjustment similar to the column shortening exercise so the analytical column extends to the floor level defined as the base of the column in question.
Q: Can RAM generate a 3D PDF directly (from RAM)?
A: No. However, you can use Structural Synchronizer to create a 3D PDF from any RAM Structural System model by creating (or updating) an ISM repository. Similarly, you can use the ISM Revit link to create a 3D PDF out of your Revit project. The ability to create a 3D PDF directly from RAM is scheduled to be included in V14.05, due out this summer.
Q: How does RAM handle sloped roofs/diaphragms?
A: Sloping floors, roofs, or diaphragms can be modeled in the RAM Structural System by simply using the Modify Elevation tool and then specifying the top-of-column offset (extend or shorten). See also the [[Modeling a Sloping Deck TN]] wiki topic.
Q: What precautions should we use when modeling in Revit for exporting to RAM?
A: Please refer to the Starting in Revit section in our [[RAM Revit Link Best Practices]] wiki topic.
Q: Will Bentley be continually updating this link or is the future the ISM link?
A: This link is going to be updated in the future as needed. We plan to maintain the link so long as it has features which aren’t available though ISM. However, there are likely to be future features of either the RAM Structural System or Revit Structure which will only be possible to exchange through the ISM Revit plug-in.
Q: When you modeled the cant., it appears that you did not model it to follow the curved grid. Can you model the cant. beam to match the grid curve?
A: No. Members in RAM must be linear members. However, the curved grid for this model is solely for column layout. All beams are straight, including the back spans of the two cantilevered beams modeled during this demo.
Q: Does ISM support Revit 2012?
A: Yes. Revit Structure 2012 (both 32- and 64-bit) are supported as of v2.1 of the ISM Revit plug-in, along with Revit Architecture and Revit MEP. Revit Structure 2012 is also supported by the RAM - Revit link.
Q: Typically when we import RAM into Revit, the RAM model elevation is 0'-0" and Revit model is at 100'-0". How do you adjust this elevation?
A: Use the Settings dialog Offset tab to specify the translations (which may be simply zero).
Q: Any timeframe on a future Revit ISM Webinar?
A: We do plan to have some seminars planned in a few months for Integrated Structural Modeling and Revit integration will play a key role in this.
Q: Can the link translate "future" phases of construction for RAM analysis?
A: No. The link does not support Revit phases.
Q: What is the best way to handle vertical offsets (2 1/2" bar joist seats for example) in Revit to RAM? Do we need to establish separate story levels?
A: Like the earlier question this should be setup when they are creating the model and not adjusted later.
Q: Why the TOS elevation coming from Ram into Revit matches the TOC of the slab? We have to manually adjust the TOC of the slab after the import...Any comments on how to handle this issue other that adjust after importing into Revit?
A: This is correct. The slabs do come into Revit with the top of slab at top of steel level. I simply neglected this and didn’t change my settings. You can offset the slab location then uncheck the option to update slabs or they will move back to the top of steel level on subsequent imports. This is because the slabs are handled so differently between RAM and Revit that they are actually deleted and recreated on import.
Q: How does a beam offset from a floor in Revit translated into RAM?
A: Currently, the beam offset must be made in the Revit physical model only and the analytical members remain co-linear. Rigid member offsets — available in the RAM Structural System later in 2012—will be able to accommodate analytical offsets which would result in different structural behavior (torsion, moment, etc.).
Q: When bringing a concrete wall in to Revit from RSS, does it bring the reinforcing along? (Will the reinforcing show up in Revit?)
A: No. The rebar designs are not supported by the RAM – Revit link. Rebar is partially supported using ISM and that will be required to transfer reinforcing designs in future versions.