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The locations of columns and wall cannot be changed in RAM Concept. If the support locations must be changed, the RAM Structural System model should be modified and re-imported into RAM Concept.
Adjustments to slab areas and beam elements (geometry, sizes, etc) can be done in RAM Concept following import of the RAM Structural System model. Any change affecting lateral members may alter the load path of lateral loads and should also be made in RAM Structural System.
Important - if you are making changes to the slab, drop caps beams or openings in Ram Concept Mesh Input - Standard Plan, then it's important not to update those objects when Syncing to the RAM SS model later. Simply uncheck those items from the File - Sync Ram - Update from RAM Structural System... dialog box, or similarly unchek those items from Ram manager - Design - Ram Concept as indicated below.
Beams in RAM Concept are meshed with the slab. For continuous beams modeled in RAM Concept, it is not necessary to model the beams in segments from column to column. Meshing problems are often prevented by modeling continuous beams as one beam segment from outside face of the first column to the outside face of the last column bypassing each intermediate column. Beams modeled in RAM Structural System are modeled support to support. When the beams are imported into RAM Concept, they are brought into the program as segmented members between each support. In most cases, there will be multiple overlapping areas at the column (see Figure1 below). Since this can produce meshing errors in some cases, it is often easier to not import beams and then create them in RAM Concept after the model is imported and modeling as a continuous beam (see Figure 2 below).
Figure 1. Beams Segmented at Column After Importing.
Figure 2. Model Beams as Continuous Beams in RAM Concept.
The slab in the RAM Concrete and RAM Frame analysis is assumed concentric with beam elements (i.e. the slab passes through the centroid of the beam section). The slab in RAM Concept can be modeled at any elevation, and slab and beam systems will be imported with the slab at the proper elevations. In RAM Concept, the difference in centroid between the beam and slab element produces an eccentricity that will produce additional moments in T-shaped beams from the axial forces in the slab and beam elements. There is no eccentricity of axial forces in beams and slabs in the RAM Structural System model. Please see RAM Concept T-Beam and Axial Forcefor more information.
Slab cracked section factors in RAM SS are imported and used in the Ram Concept Slab Behavior properties. When performing a cracked section analysis in Concept as part of a detailed Service Design Rule Set or as part of a Load History Analysis, the behavior properties for the slabs should be reset to standard values (1.0) to prevent double counting of the cracked stiffness reduction.
Imported beams are set to no-torsion beams by default. The other bending cracked factors are all set to 1 and there are no end releases for beams possible in Concept regardless what was entered in RAM SS.
Currently, there is no way to import the results of a dynamic response spectrum analysis from RAM Frame into RAM Concept. There are two basic approaches to dealing with this limitation:
(1) In RAM Frame, create an “equivalent” static load case using a User Defined Story Force, one that generates the same total shear at each level (usually determined from the building story shear report). Then import the reactions from this static load case into Concept.
(2) In Concept, manually create a new seismic load case (Criteria – Loading – New, with type normal). On the load layers for that loading, add point loads (or line loads) based on the reactions from RAM Frame. Be aware, that a dynamic analysis, by default, produces forces all of like sign. If you are not already considering sign in the RAM Frame analysis (Criteria – General), we suggest you do so. Otherwise, manually establish the probable sign for each of the reactions so that the forces input into Concept represent a concurrent event.
Currently, there is no way to use Ram Concept template files when generating a new Concept file from RAM Structural System. Furthermore, design rules and load combinations are rebuilt each time the model is imported.
Please see RAM Concept-RAM Structural System Integration for additional help links.