Release Date: January 26, 2009
This document contains important information regarding changes to the RAM Structural System. It is important that all users are aware of these changes. Please distribute these release notes and make them available to all users of the RAM Structural System.
RAM Structural System V8i is part of the Bentley Systems V8i family of products. It is part of a coordinated release of the entire set of Bentley programs. Its intent is to create a common identity between all of the Bentley programs, indicating the growing integration between these programs. V8i is not a reference to a version number; this is Release 13.0.2, or Version 13.0.2, of the RAM Structural System.
Version 13.0 automatically converts databases created in previous versions to the new database format. Note that a backup file is created automatically when a database is converted; the name of the database is the same, with "Orig" and the version number appended to the name. The file has an extension of ".zip" and is located in the same directory as the original database.
The previous steel tables and load combination templates supplied with the program will be replaced with new tables and templates of the same name. If you have customized any Master or Design tables or load combination templates supplied with the program without changing the file names, those file names should be renamed from the original RAM table names prior to installation to prevent your changes from being lost.
AISC 341-05 OMF Continuity Plates:Rather than merely referring the user to the specifications, the program now checks Ordinary Moment Frame joints for the requirements of continuity plates per Section 11.5 of AISC 341-05, and designs them if necessary.
Since the release of V13.0, some program errors have been identified and corrected for Version 13.0.2. Corrections made to graphics, reports, Modeler functions, program crashes, etc that were considered minor are not listed here. The noteworthy error corrections are listed here in order to notify you that they have been corrected or to assist you in determining the impact of those errors on previous designs. These errors were generally obscure and uncommon, affecting only a very small percentage of models, or had no impact on the results. The errors, when they occurred, were generally quite obvious. However, if there is any question, it may be advisable to reanalyze previous models to determine the impact, if any. In each case the error only occurred for the precise conditions indicated. Those errors that may have resulted in un-conservative designs are shown with an asterisk. We apologize for any inconvenience this may cause.
Converted ModelsCONCRETE DECKS: When models from previous versions are opened in V13.0 or V13.0.1 they are automatically converted to the newer database format. Due to an error in the converter the usage count for concrete decks was set to 0. This would then allow the user to delete that deck property in the PropTable - Decking command, even if that property was currently being used in the model.Effect: This error had no impact on the designs, analysis, etc., unless the user attempted to delete a deck property that was currently in use in the model, in which case the database could have become corrupt. The user is advised to check carefully before deleting a deck property in PropTable - Decking if the model was created in a previous version, and then converted to V13.0 or V13.0.1.
ModelerEDIT GRIDS: In some cases a brace would not move when the grid that corresponded with its endpoint was moved.Effect: Braces became attached to the wrong place on beams, or became detached from the beams entirely.
CHANGE LOAD POLYGON: In some cases creating or deleting a surface load polygon vertex using the Layout - Loads - Surface - Change Polygon command corrupted the point load assignments.Effect: Point loads may have been relocated or removed entirely.
Framing Tables:SLOPING COLUMNS*: When a sloping column was supported by a transfer girder, the program incorrectly placed the transfer column load on the girder based on the coordinates of the top of the column rather than the coordinates at the bottom of the column.Effect: Transfer loads were placed at the wrong location along the girder.
RAM Steel ColumnCAN/CSA S16-01 UNIAXIAL STRONG AXIS BENDING: For columns of Class 1 and 2 under uniaxial strong-axis bending, the value of Cr calculated using clause 13.8.2(b) was using the smaller of Crx and Cry, even though Cry is not required in that case.Effect: For CAN/CSA S16-01 (Canada) designs, the calculated Cr may have been conservatively limited to Cry for Class 1 or 2 members.
CAN/CSA S16-01 HSS AND CLASS 3 I-SHAPES*: For HSS sections, and for I-shaped sections in Class 3, a beta factor of 0.6 was erroneously applied to the My bending term for the calculation of the cross-sectional strength in the interaction equation of clause 13.8.3.Effect: For CAN/CSA S16-01 (Canada) designs, the interaction equation result may have been unconservative because a beta factor of 0.6 was applied to the My term in the cross-sectional strength check (the beta factor should not be applied for HSS and Class 3 I-shapes). Designs were only impacted if that equation should have controlled.
RAM Frame - AnalysisRESPONSE SPECTRA ANALYSIS*: Response spectra analysis results were incorrect when ASCE 7 seismic load cases and response spectra load cases were analyzed simultaneously. Effect: Incorrect results for response spectra analysis cases. Note that the results were correct if no ASCE 7 seismic load cases were included in the analysis.
RESPONSE SPECTRA ANALYSIS SIGN: When response spectra load cases were analyzed, the Consider Sign option in the Criteria - General command would automatically become selected, and the signs would be applied to the analysis results.Effect: The program applied signs to the response spectra results even if the user had not selected the option to do so.
RESPONSE SPECTRA REACTIONS DISPLAY: Reactions for response spectra load cases were displayed on screen in the wrong direction (but with correct values).Effect: Graphics error only (reports and analysis results were correct).SLOPING COLUMNS: When frame column supported multiple frame columns from above, the gravity loads from those columns was duplicated.Effect: Extra gravity loads were applied to the frame columns for the condition indicated.
CHINA GB50011-2001 WIND*: The program use a wind pressure of zero at the base of building. According to GB50011-2001, a constant wind pressure should be applied for heights less than 5m. Effect: Incorrect loads were applied at first story.
RAM Frame - Steel Standard ProvisionsB2 FOR SEMIRIGID DIAPHRAGM*: Currently the program calculates the story drift values at the story center of mass for the calculation of B2 (AISC 360-05 stability coefficient). If the center of mass was located inside an opening or outside of the diaphragm, the program used 0.0 for the story drift which then resulted in B2=1.0 for these cases.Effect: In very rare cases, B2=1 was reported for semirigid diaphragms when the diaphragm center of mass was located outside of the diaphragm boundaries or within an opening.
RAM Frame - Steel Seismic ProvisionsHSS WIDTH-THICKNESS LIMITATIONS*: For HSS sections used in systems required in AISC 341-05 to satisfy the requirements of Section 8.2a Compact, the program was applying the width-thickness limits as for "Flexure in webs of rectangular HSS" of AISC 360-05 Table B4.1. However, since the member may be in full compression the more stringent width-thickness limits as for "Uniform compression in flanges..." should have been applied.Effect: The program allowed some non-square HSS sections based on the less stringent width-thickness requirements but should have failed them due to the more stringent requirements.
Four versions of the RAM Structural System were released in 2008. These versions contained several significant enhancements. Those enhancements are listed here for your convenience.
Sloping ColumnsSloping columns can now be modeled, analyzed and designed. They are modeled by first adding columns to the desired locations using the Column Add commands, and then by moving either the top or the bottom using the Layout - Column - Move command or the Layout - Column - Text command.
Sloping columns can be of concrete, steel or any material; they can be gravity columns or frame columns. The effects of the slope on the unbraced length, self weight, joint face dimensions, etc., are automatically considered.
Semirigid Diaphragms:In addition to the options to specify diaphragms as Rigid, Flexible or "Pseudo-flexible", an option to specify a diaphragm as Semirigid has been incorporated in the Criteria - Diaphragm command in RAM Frame. In the Modeler the PropTable - Decking command has been enhanced to allow the specification of the diaphragm properties associated with each deck or slab. These properties are then used for the diaphragms that are specified as Semirigid when an analysis is performed in RAM Frame. This allows the interaction between the diaphragms and the frames to be considered when determining the distribution of the story forces to the frames.
The diaphragm is automatically meshed; the density of the mesh can be controlled by the user with an option in the Criteria - Diaphragm command. The mesh can be viewed using the View - Meshed Floors command in RAM Frame.
Wind story forces are applied to the diaphragms as windward and leeward loads on the mesh nodes around the perimeter of the structure. Seismic story forces are applied to each mesh node based on the tributary mass to that node. The applied forces can be viewed using the Process - Results - Applied Story Forces command.
A current limitation is that stories with sloping beams / sloping diaphragms can not be specified as Semirigid. That will be addressed in a future version.
ProjectWise:The RAM Structural System has now been integrated with ProjectWise, Bentley's project management software. For clients with ProjectWise, this functionality can be accessed using the File - ProjectWise command in the RAM Manager. Go to www.bentley.com for more information on ProjectWise.
ACI 318-05 Concrete Design:The requirements of ACI 318-05 have been incorporated for concrete beam and column design in RAM Concrete, and for foundation design in RAM Foundation.
Australia Concrete Design:The requirements of AS 3600, the Australian Concrete design specification, have been incorporated for concrete beam and column design in RAM Concrete.
Model Status:The Model Status feature, which shows the current state of the model, has been enhanced. The use of the status lights has been made consistent for all modules. In the RAM Manager the File - Model Status command, which can also be launched directly from the Manager screen, now includes a key to the status light colors. The status light now shows as light blue for modules for which some action or additional data must be entered before analysis and design can be performed in that module. Modules for which there are no pertinent members now show as gray.
Tutorial Wiki:The Tutorial manual has been put on a wiki on the BE Communities site. It can be accessed from the program using the Help - Tutorial Wiki command in the RAM Manager.
Modeler:• The Column - Move command has been enhanced. Previously the new coordinates or offset had to be entered numerically; now the new location can be selected graphically by clicking on that location. The ability to move the top and bottom of the columns independently has also been incorporated, providing a means of modeling sloping columns.• The Column - Text command has been enhanced such that when the coordinates of the top of a column are changed, the beams that frame into that column also move to the new location. The ability to move the top and bottom of the columns independently has also been incorporated, providing a means of modeling sloping columns.• The Noncomposite Floor System tab of the PropTable - Decks command has been enhanced to allow the specification of multiple noncomposite decks. Previously only a single noncomposite deck type was allowed. A Label has also been added to distinguish between the various noncomposite deck types.• Deck diaphragm properties for use when the deck/slab is specified as Semirigid in RAM Frame can be specified using the PropTable - Decks command.• The dialogs listing the deck properties when using Change and Show in the Layout - Slab - Deck Assign command have been improved and reorganized to better show the deck properties.• In the Datacheck report, the Errors are listed in red, the warnings are listed in black.
RAM Steel Beam:• A Find Beam command has been added. It can be invoked using the View - Find Beam command or the button on the toolbar. The beam briefly flashes when the beam number is entered.
• The beam design program, RAM SBeam, can now be launched directly from the RAM Structural System using the Process - Export to SBeam command. When invoked, the geometry, loads and criteria of the selected beam are exported to RAM SBeam. Using the same design algorithms as RAM Steel Beam, RAM SBeam is a powerful yet economical utility program for the design of composite and noncomposite steel beams. Contact your regional engineer for more information on RAM SBeam.
RAM Steel Column:• The calculation of the unbalanced moment was slightly modified. In the general case the unbalanced moment is split between the top of the column and the bottom of the column above. Previously if there was a change in shape at a level (e.g., from I-shape to HSS) the program assumed that the splice essentially behaved as a pin connection, and no portion of the moment was applied to the bottom of the column above; the full moment was applied to the top of the column under consideration. Now, in addition to the change in shape, a change in column orientation or material is treated the same way, the unbalanced moment is not split between the column under consideration and the column above, it is all applied to the top of the column under consideration.
RAM Frame:In addition to the Semirigid Diaphragm capability, RAM Frame has been enhanced with new features, including:• A new, faster solver has been incorporated. There is now an option in the Criteria - General command to select between the Direct Solver and the Sparse Solver. Both solvers have the option of running In-Core or Out-of-Core. The Direct Solver is that which was used previously, and gives more detailed messages when error conditions are encountered; the Sparse Solver runs significantly faster but gives less detailed information when error conditions are encountered.• In the calculation of self-weight loads and masses from walls, the presence of openings in the walls is now considered and subtracted from the loads and masses.• Braces can be designated as Buckling Restrained using the Assign - Braces - Buckling Restrained command. An axial stiffness multiplier can be assigned to account for the fact that the yielding steel core section only extends for a portion of the full node-to-node brace length considered in the analysis. In the code checks for those braces the stress and capacity equations based on the buckling modes are ignored, and the design is based on core section yielding.• China GB50011-2001 has been incorporated for the generation of Wind, Seismic and Response Spectra load cases.
RAM Frame Steel Standard Provision:• Values of Unbraced Length used in the design for bending and for axial loads can now be assigned to beams, columns and braces using the Assign - Beams - Unbraced Length, Assign - Columns - Unbraced Length and Assign - Braces - Unbraced Length commands. Options are given to either use the assigned value or to calculate the value based on the geometry and the Flange Bracing criteria specified in Criteria - Flange Bracing.
RAM Concrete Column:• The graphics in the View/Update have been enhanced to show the column cross section with the design reinforcing.
RAM Concrete Shear Wall:• Boundary Element Design is now performed per the ACI concrete specifications.• Multiple vertical reinforcing zones may be assigned to the wall panels, allowing greater control of the reinforcing patterns along the length of the wall.• Shear Wall material Takeoff report has been incorporated.• Shear Wall DXF is available with the Post-Processing - DXF File - Shear Wall command in the RAM Manager.
AISC 341-05 Seismic Provision:The requirements of AISC 341-05 Seismic Provisions have been incorporated for member and joint design in RAM Frame in the Steel - Seismic Provisions mode.
Concrete Shear Walls:The following enhancements have been made to the Concrete Shear Wall Design module:• Drastic improvements have been made to the speed of the design process when executing Design-All or View-Update.• An option to save the design results for only the most critical load combinations has been added in the General Criteria. Choosing to save design results for fewer load combinations will reduce file size and program run time.• The engineer now has control over how vertical reinforcement is placed at wall corners through use of the Assign - Wall Panel Priority command.• A new calculation sheet "Boundary Elements" has been added to the View/Update dialog when ACI 318-05 is used. This page reports information related to the special boundary element calculations of Chapter 21 for any load combinations containing an earthquake load case.• For the ACI 318-05 design code, the option to calculate wall shear strength according to Section 11.10.6 has been provided. Section 11.10.6 may now be used in lieu of Section 11.10.5.
Live Load Reduction:The Live Load Reduction requirements for AS/NZS 1170.1 (Australia and New Zealand), GB 50009-2001 (China) and Hong Kong Building Regulation have been incorporated. Those building codes can be invoked using the Criteria - Member Loads command in the RAM Manager.
File commands:A File - Close Model command has been added. This is useful when working with external programs (such as RAM Concept or RAM Connection) that require the model to be closed in order to access the information in the database.
Consistent Window Sizing:Rather than always come up in full screen mode, the RAM Modeler and the design module windows will maintain a consistent window size and location on the screen.
RSS Feed:The RSS (Really Simple Syndication) feed items on the lower portion of the RAM Manager screen can now be directed to specific regions. Feed items directed to regions other than the region that the user is in can be filtered out using the Tools - RSS Feed Options command. Note that the Worldwide feed items and the feed items directed to the region that the user is in can not be filtered out, those will always be received.
Modeler:Deck polygons that have been laid down can be modified using the Layout - Slab - Deck Assign - Change Polygon command. Snow load polygons that have been laid down can be modified using the Layout - Loads - Snow Loads - Change Polygon command. Polygon vertices can be dragged to new locations, adjacent vertices can be merged, and new vertices added by splitting a side into two sides. This feature was implemented for Surface loads previously.
RAM Frame:In addition to the requirements of the AISC 341-05 Seismic Provisions, the following enhancements have been incorporated:• An option to include the requirements of Supplement #2 of ASCE 7-05 has been added when generating seismic story forces per ASCE 7-05.• Notional Loads per BS 8110 can be generated using the Loads - Load Cases command.• The ASCE 7 Stability Coefficients report has been added. This report calculates and lists the Stability Coefficient for each ASCE 7 and IBC Seismic load case. It can be obtained using the Reports - ASCE 7 Stability Coefficients command.• Crack factors for each of Flexural, Axial and Torsional stiffness of concrete beams, columns and braces can be assigned in the Modeler, and applied to frame members in the analysis performed in RAM Frame. Previously only a flexural crack factor could be assigned. Note that for models created in previous versions the cracked factors for axial and torsional stiffness of columns, beams and braces will be set to 1.0 when they are opened in V12.1, to be consistent with the values used previously, but they can be modified in the Modeler as desired.• K-factors can now be assigned to braces even when the design code is AISC 360-05 (when K is normally considered to be 1.0). This allows, for example, the assigning of K = 0.5 to cross braces to account for the bracing effects of the cross braces.• Clicking the right mouse button now brings up the previous dialog box, making it consistent with the Modeler and the other design modules.• The Wall Group Force Summary report command has been enhanced to allow selection of specific walls and wall groups to be included in the report. Previously the report always included the results for all wall groups.
RAM Concrete:• For large models the option of using the out-of-core solver is now available in the Criteria - Analysis command.• The Singapore concrete design code, CP65, has been added to RAM Concrete.• In addition to the option to consider gravity columns pinned at the base at foundations, an option to consider the columns pinned at the base at transfer girders has also been implemented. An option to consider gravity columns pinned at the top has also been implemented. These options are available in the Criteria - Analysis command.• Previously there was an option in the Criteria - Analysis command to specify a reduced torsional stiffness on beams. There is now a capability to assign a torsional crack factor in the Modeler, so that command has been enhanced to allow the user to either specify the use of that factor or the use of the factor explicitly specified in the command.
Concrete Shear Wall Design:The RAM Concrete Shear Wall Design module has been added to RAM Concrete in the RAM Structural System. The Shear Wall Design module provides the complete design of vertical and horizontal reinforcing in concrete walls according to the requirements of ACI 318-05 and BS 8110-97. The task of designing walls is highly automated, including the selection of reinforcing steel, calculation of design forces, generation of design combinations and determination of critical design sections. Designs can be optimized or interactively modified and analyzed. Reinforcement may be automatically selected by the program or specified directly by the engineer. RAM's trademark View/Update feature has been tailored to the wall design process, allowing for easy yet thorough review and revision of the design results.Among the many advantages of the Shear Wall Design module is its integration with the RAM Structural System. Changes to the model geometry and design loads are reflected immediately in the RAM Concrete environment, eliminating the need to manually reapply or transfer wall forces into a non-integrated wall design environment. In addition, the Shear Wall Design module can handle complex wall and wall opening geometries that most current solutions simply do not allow. Refer to the Shear Wall manual for more information.
Flexible Diaphragms:In addition to the option to specify diaphragms as rigid, an option to specify a diaphragm as "pseudo-flexible" has been incorporated in the Criteria - Diaphragm command in RAM Frame, allowing the user to specify the percent of the total story force at that level to be applied to each frame, using the Loads - Pseudo-Flexible Diaphragm Properties command. This provides the user a simple and effective means of controlling the distribution of story forces when the diaphragm can not be considered rigid.
File commands:• The File - New, Open and Save commands have been updated.
Modeler:• Surface load polygons that have been laid down can now be modified using the Layout - Loads - Surface Loads - Change Polygon command. Polygon vertices can be dragged to new locations, adjacent vertices can be merged, and new vertices added by splitting a side into two sides.• Beam Generation: A new option has been incorporated for generating beams at an equal spacing along the primary beams not to exceed the maximum allowable spacing specified by the user.• Deck Orientation: For specifying the orientation of the deck there is now the ability to Pick a beam to which the deck is parallel or perpendicular.• The Zoom and Scroll commands can be invoked while laying down deck and load polygons without disrupting the polygons.• The Options - Set Snap Points command now has Select All / Deselect All buttons.• The Options - Set Show Options command now has options to show unclipped load and deck polygons, whereby the polygons will be displayed without being clipped by the slab edges.
RAM Steel Column:• A View - Nonpertinent Members command and toolbar button has been incorporated which allows the user to specify how nonpertinent members (i.e., those that are not pertinent to the design module, such as beams in the Column module) are displayed: Draw Normal, Draw as Lines, or Hide.
RAM Frame:In addition to the Pseudo-flexible Diaphragm capability, RAM Frame has been enhanced with several new features, including:• A new, more versatile and accurate wall element has been implemented, with an option to include out-of-plane stiffness. That option can be selected in the Criteria - General command.• A scheme for recovering and applying signs to the Response Spectra analysis results has been implemented. That option can be selected in the Criteria - General command.• Frame Story Shears can be displayed on-screen using the Results - Frame Story Shears command.• The Process - Results - Member Forces command has been enhanced to allow selection of member types (beams, columns, braces or walls) for which the member forces are to be displayed.• A toolbar button to show and hide Frame Numbers has been added.
RAM Concrete:In addition to the new Shear Wall Design module, the following enhancement has been incorporated:• A View - Nonpertinent Members command and toolbar button has been incorporated which allows the user to specify how nonpertinent members (i.e., those that are not pertinent to the design module, such as beams in the Column module) are displayed: Draw Normal, Draw as Lines, or Hide.
Deck Table:• The deck table for the UK has been updated to include the SMD TR80, TR60 and R51 profiles.
AISC 360-05: The latest steel design specification, AISC 360-05 as published in the AISC Steel Construction Manual 13th Edition, has been implemented. The provisions for both ASD and LRFD have been implemented for the member and joint code checks. The provisions for slender members have also now been implemented. Design of composite and noncomposite beams, columns, baseplates, braces and beam web openings has been updated. The option to use the previous ASD and LRFD specifications is still available.Direct Analysis Method: The requirements of the Direct Analysis Method of AISC 360-05 have been implemented. Options for 2nd-order analysis include a P-delta analysis based on the Geometric Stiffness method (which includes the effects of ‘leaning columns') and a second-order analysis by amplified first-order elastic analysis (B1 and B2 factors) as given in the Specification. Story loads for Notional Loads are automatically calculated, and Notional Loads can be generated. Options to use Reduced Stiffness are available. IBC 2006 Load Combinations can be automatically generated.RSS Feed: An RSS (Really Simple Syndication) feed on the main screen provides up-to-date announcements of program releases, downloads, seminars and training events. Clicking on a message will open a related web page in your web browser.Free-form Slab Edges: Slab edges can now be modeled as free-form slab edges, allowing for the modeling of more complex edges, including the ability to vary the slab edge distance along the length of the beam.Steel Tables - US: The Steel design tables for the US have been updated to reflect the properties of the currently available steel sections as outlined in the Steel Construction Manual. The HSS column tables have been refined to give better, more consistent column designs.Steel Tables - UK: The Steel design tables for the UK have been updated to include the Corus Advance sections. The deck tables have been enhanced to include the Tegral ComFlor decks, with the capability of designing those decks with FibreFlor steel fibre reinforcing. The new Corus and Tegral ComFlor 60 deck has been added.Square Baseplates: The baseplate design capabilities of the Steel Column Design module have been enhanced to allow the engineer to specify square baseplates, even though smaller rectangular baseplates may be adequate; this conforms to common design practice.Baseplates on Pilasters and Walls: Baseplates of columns supported on concrete columns and walls are now designed, not just those that are supported directly on the footings.RAM Frame Enhancements: RAM Frame has been enhanced with new usability features, including:• A Find command to find specific members and nodes has been added to the toolbar.• A Hide/Show Gravity Members command has been added to the toolbar.Concrete Beam Shear Design: In the RAM Concrete Beam design module the design of shear reinforcement has been enhanced:• There is now a better correlation between the shear zone callouts and the actual stirrup locations.• When two adjacent shear zones share an end point, the zone with the larger As/ft will govern, and a stirrup of this type will be placed at the end point.• The shear zones are now measured from the first stirrup location, rather than from the column centerline.As a result of these enhancements, when the program uses three shear zones the outer zones will, in the majority of cases, be an even multiple of the shear segment increment specified in the criteria.BS 5950 Load Combinations: The load combination generator template for BS 5950 has been enhanced to give the option of using either the Exceptional Snow load factor (1.05) or the Imposed load factors (1.6, or 1.2 when with wind or seismic loads) for the factor on the snow load components. It has also been enhanced to give the option of generating the gravity combinations without the notional loads as well as with the notional loads (those additional combinations without the notional loads are not required, but some engineers prefer to see the results of those combina-tions included in the design of members).Modeler Datacheck: The Datacheck has been enhanced to detect and delete zero-length slab edges. These can be created when grids, columns or beams are moved. Previously the program may have crashed, now the Datacheck removes them.