RAM SS Common Framing Table Errors [TN]
| Applies To | |||
| Product(s): | RAM Structural System | ||
| Version(s): | 13.00.00.00 or later | ||
| Environment: | N/A | ||
| Area: | N/A | ||
| Subarea: | N/A | ||
| Original Author: | Bentley Technical Support Group | ||
Framing Tables Errors
General
There are many instances where modeling errors in Ram Structural System are not caught by a Data Check in Ram Modeler. Data Check looks at general geometric information, but it does not attempt to validate all of the information needed to compile the Ram Gravity Framing Tables.
Many of these errors are slab edge or slab opening related. When one way decking is modeled, slab edges and slab openings must be associated with adjacent beams/walls. For this reason, avoid using free formed slab edges/openings with one way decking. Instead, use Layout - Slab - Slab Edge - Whole Perimeter and Layout - Slab - Slab Opening - In Bay to model the slab edges and slab openings. Then, revise the slab edges/openings where the offset changes. To further ensure accuracy, only use beams and walls in your Options - Set Snap Points. Finally, use a positive, non-zero, slab edge offset. Zero inch slab edge offsets are permitted, but the program algorithms were originally developed assuming non-zero offsets and some configurations can be problematic.
Below are several common modeling configurations that cause problems for the program but are not caught by Data Check. The right hand image shows the typical error message produced while building the framing tables. In the background, the framing tables usually halt at a particular member on a particular floor as shown in the left hand image. Typically, but not always, the modeling issue occurs in the vicinity of the member where the framing tables halt.
Illegal Framing Configuration
Most illegal configuration errors are slab edge or slab opening related. Subtle inaccuracies in member end locations can cause small slab edge segments that are problematic for the framing tables. Review the member end coordinates using the Layout - Beam - Show command and the slab edge coordinates using Layout - Slab Edge - Show. Try remodeling the slab edge using the whole perimeter command.
Missing Slab Edge
Many missing slab edge errors are related to having portions of the structure isolated from the perimeter beam loop under one way decking as shown below. To resolve the issue, model two beams that connect the isolated structure back to the adjacent framing. If these beams are modeled parallel to the deck span, they will take no tributary load from decking.
Internal Error in AdvanceNodeList()
Typically, these errors are similar to the missing slab edge error. The main difference is that there usually is only a single beam/wall connecting the interior structure to the perimeter beam loop as shown below. Modeling a second beam will resolve the issue.
Beam Loop Intersection not Found
Typically, beam loop intersection errors are related to line loads that are slightly askew from a beam. Often discrepancies arise when a single line load is added over multiple beams that are not truly collinear. Review the coordinates of the beam and line load using the Layout - Beam - Show and Layout - Load - Line Load - Show command. To resolve the issue, delete the line load(s) and remodel them using the Add On Beam command.
This error can also be associated with changes in one way deck orientation or properties. One way decking should always transition along a beam/wall. That includes transitions from one way decking to two way decking.
Failed to Find Slab Edge Loads
These errors are usually related to tolerance problems between the slab edge loop and perimeter beam loop. Review the slab edge and beam coordinates using the Layout - Slab - Slab Edge - Show and Layout - Beam - Show command. Try remodeling the slab edge using the whole perimeter command.
Forcinga"Reframe"
Insomecasesthebeamdesignmodulecanopenandnotrequirearebuildingoftheframingtables,whatiscommonlyreferredtoasareframe.Areframeisgenerallytriggeredbymakinganykindofchangeonaparticularlevel.YoucanalsoforceareframebychanginganyoftheRamManagercriterialikeSelfWeightorLiveLoadReductioncode.
Ifthedesignmoduleproducesanunexpectederror,onesimplethingtotryisforcingareframe.Youcanchangeonethecriteriamentionedabove, andclickOK.Youshouldgetawindowlikethisifpreviousresultsaregoingtobediscarded:
Thenchangethecriteriabackthewayitshouldbeandtry thebeamdesign again.
See Also
Structural Product TechNotes And FAQs
External Links
Bentley Technical Support KnowledgeBase
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