Issues Found in version 15.04.00 are noted here. Click below for
All RAM Structural System Defects fixed in version 15.04.00
RAM Structural System Release Notes
Issues Found in version 15.05.00 are noted here.
All RAM Structural System Defects fixed in version 15.05.00
RAM Structural System Release Notes
| Applies To | |||
| Product(s): | STAAD.Pro | ||
| Version(s): | 20.07.10.00 and later | ||
| Area: | Licensing - Technical | ||
This support solution provides steps to disable RAM Connection integration within STAAD.Pro.
STAAD.Pro includes an integrated version of RAM Connection that is accessible to engineers from the RAM Connection tab. Such integration, while useful, also provides a potential source of unintentional use for the RAM Connection license. Fortunately, STAAD.Pro provides a configuration setting for enabling or disabling the integration. Following are steps for disabling it.
Once disabled, an engineer will encounter an error when attempting to access the RAM Connection tab.
Only very basic functionality that does not require a RAM Connection license will be available.
Conversely, if you do want to use the full Ram Connection functionality within STAAD.pro, make sure the option is checked.
On the STAAD.pro CONNECT Edition Open screen, in the lower right corner, make sure that the RAM Connection box is unchecked if you do not want to utilize a RAM Connection License during this session.
Tips for Using RAM Connection within STAAD.Pro [TN].
[[Error getting a RAM Connection License with STAAD.pro SS5]]
| Applies To | |||
| Product(s): | RAM Structural System; Ram Frame | ||
| Version(s): | Any | ||
| Area: | Analysis | ||
Red status lights are shown to the left of wind and seismic load cases in RAM Frame - Process - Analyze. These load cases cannot be analyzed.
When wind and seismic load cases are defined to use the calculated frequency and period, the program is required to run an Eigen Analysis to find the fundamental frequency and period for each direction. If there is insufficient information to solve the Eigen Analysis, red status lights will be displayed on the left of the load case and you will not be able to include them in the analysis.
Two common reasons for the red status lights:
Consider using one of the following to work around this issue:
Structural Product TechNotes And FAQs
[[Ram Frame - Masses]]
RAM Structural System CONNECT Edition Update 5 Release 15.05 Release Notes
Release Date: July 19, 2017
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.
Bentley CONNECT:
Bentley CONNECT offers several benefits, and the value continues to increase with each new release. Listed here are three key features.
CONNECTION Center
When you sign in to your Bentley account you now have easy access to CONNECTION Center. This personalized portal gives you easy access to Usage reports, site configuration information, downloads, and Learning information on webinars, seminars and events, and includes a transcript listing the Bentley courses that you have completed. Your personal portal also lists your recent projects with a portal into analytics on that project. CONNECTION Center can be accessed by selecting the Sign In command in the upper right corner of the RAM Manager screen.
If you do not already have a Bentley ID, go to http://www.bentley.com/profile and select the Sign Up Now link.
CONNECTED Projects
All of Bentley’s CONNECT Edition programs, including RAM Structural System, allow models to be associated with a project. Multiple models, from any of the Bentley products, can be associated with a given project. This simplifies the process of keeping track of work done for a project, and will enable analytics to be performed and reported for the project.
A ProjectWise Projects portal enables you and your project teams to see project details required to evaluate team activity and understand project performance.
When a model is Saved in this version the program will ask for a Project to which the file is to be associated. Projects can be registered (created) from your Personal Portal, or from the Assign Project dialog by selecting the + Register Project command.
Update Notification
Notification is given when an updated version of the RAM Structural System is available. The update can be downloaded and installed simply by selecting the link in the notification.
Tutorial:
The Tutorial Manual has not been updated but is still valid. The appearance of some parts of the program in this version may differ from that shown in the Tutorial.
Important Notice:
This version 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.
Installation Instructions:
This version can be found on the Bentley Software Fulfilment web page by logging into the Personal Portal or the Enterprise Portal and selecting the Software Downloads icon. Perform a search for “RAM Structural System”, select any of the RAM Structural System modules (e.g., RAM Modeler; they all use the same installer), and select the latest version of the RAM Structural System.
Product Licensing FAQ:
Appendix Ccontains a document describing features available in the RAM Structural System to help prevent inadvertent use of unlicensed modules. Refer to that document for more information.
New Features and Enhancements:
For details on these new features and enhancements, refer to the manual .pdf files available from the Help menu in each module or from the Manuals folder on your hard drive.
CONNECT Advisor
Each module has a button in the tool bar to invoke the CONNECT Advisor. The CONNECT Advisor provides links to pertinent Bentley courses, YouTube videos, Bentley Communities wikis and articles, and manuals. This provides timely information to help you better learn the capabilities of the program.
ACI 318-14
The requirements of ACI 318-14 have been implemented in the RAM Concrete module.
Note: For frame walls were special boundary elements are required, Section 18.10.6.4(b) requires a boundary zone width of hu/16, where hu is the height between braced levels. Typically this is the panel height (story height), but it is possible that walls may span through multiple levels without being braced at those levels. In the current implementation, the program uses the panel height for this check, which is unconservative if the wall spans multiple levels. This will be addressed more comprehensively in a future version.
IBC 2015
Load combination templates for steel, concrete, and foundation design based on the IBC 2015 requirements have been added.
Construction Stage Analysis
The ability to analyze the structure by construction stages has been implemented. The stage sequence can be assigned by story or by individual members, and the structure analyzed by stages for dead load. These results can then be used instead of the traditional dead load analysis. This type of analysis is especially appropriate for taller concrete structures; it acknowledges that the dead loads are applied to the structure as it is built, not suddenly after it is built. In RAM Frame, the Criteria – Construction Stage Analysis command is used to specify stages, by story. That command is also used to specify that these results are to be used in place of the traditional Dead Load analysis. The Assign – Stage Number command can be used to assign stage numbers to individual members, if different than the Stage Number otherwise assigned to the members on that story. Care should be taken when using this command not to create an unstable condition for a given stage. The Construction Stage Analysis load case can be created using the Loads – Load Cases command. Construction Stage Numbers can be displayed using the Construction Stage option in the View – Members command (or using the Construction Stage Numbers button on the tool bar). Members can be displayed stage-by-stage using the Show Stages button on the tool bar.
Diaphragm Section Forces
For semirigid diaphragms the forces across any section cut line can be reported. This is useful for obtaining the diaphragm forces used in the design of the diaphragm. This is done using the Reports – Diaphragm Forces command, selecting a Plan view, and clicking and dragging the cutline at any location on a semirigid diaphragm. Note that in order for these results to be available it is necessary to select the “Store diaphragm forces” option in the Criteria – General command.
Diaphragm Stiffness Modifiers
In addition to the ability to specify cracked section properties for concrete semirigid diaphragms that was previously available, the user can now optionally specify diaphragm stiffness modifiers for all semirigid diaphragms. The modifiers can be specified for each of the six degrees of freedom of the diaphragm elements. This is done in the Modeler using the PropTable – Decking command.
India Standards
Several India standards have been implemented for analysis and design of Steel buildings:
Global Axis Display
There is now an option to display an indicator of the global axis, located at the origin of the model.
Eurocode Buckling Resistance Moment Capacity for I-Sections
The buckling resistance moment capacity, Md,Rd, for I-Sections previously relied on the provisions of BS EN 1993-1-1:2005 Section 6.3.2.2. The provisions of Section 6.3.2.3 are now used in determining Mb,Rd for wide-flanged sections. The capacities for all other shapes are still evaluated per the requirements of Section 6.3.2.2.
Castellated and Cellular Beams
Previously in the program, castellated and cellular beams were referred to as SMARTBEAMs. They are no longer marketed or produced under that name. These beams are now called C-BeamsTM and are produced by SteelFab, Inc. The design is unchanged.
ISM
Mat foundations can now be export to ISM.
Technology Preview
This version contains two powerful features that have been designated Technology Preview features. They are features that are in a state that would previously been referred to as a Beta version. These two features are Analytical Insights and SQLite database of result. It is likely that these features will continue to undergo revisions based on feedback from users. Care should be taken if these are used for actual design, because they are still in the process of being revised; they have not gone through the rigorous testing process. They are being made available so that you can use them with real models in real design situations, and provide us with feedback and suggestions for making these features more useable and productive.
Analytical Insights – Technology Preview
The Analytical Insights feature analyzes your model and compares them with a set of Structural Performance Indicators (SPI). These SPI’s can be configured to conform to your office standards and practices, and prioritized according to their importance. Your model is then scored based on these SPI’s helping you identify possible changes to the model to make it more economical or constructable. See Appendix A for more information.
SQLite Database of Analysis and Design Results – Technology Preview
In order to more easily access the geometry and analysis data, this data is now written out to SQLite files. A report generator is provided that can be used to create a .xlsx file that can then be used in spreadsheets in Excel. The file can be customized to contain the information that you want made available. See Appendix B at the end of this document for more information.
Error Corrections:
Some program errors have been corrected for Version 15.05. 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.
DXF Output
DXF FILES IN MICROSTATION CE: DXF files created in RAM Structural System could not be opened in MicroStation CE due to unrecognized spaces before numbers.
Effect: MicroStation could not open DXF files created in RAM Structural System.
RECTANGULAR STEEL TUBE ORIENTATION: The orientation of rectangular steel tubes was off by 90 degrees in the floor framing plan DXF.
Effect: Rectangular tubes were drawn rotated 90 degrees from their true orientation.
Modeler
RIGID LINKS: If rigid links were modeled to create offset beams, and the grid associated with one end of the beam was moved, and the layout type was moved on more than one level, the rigid links were not updated to their new location at all of the levels where the floor type was used.
Effect: In a rare set of conditions as explained, rigid links were not updated at some levels if the grid associated with them was moved.
Gravity Loads
LOADS ON SLOPED GRAVITY WALLS*: When Gravity walls are supported by Frame walls, the program tracks the loads of the gravity walls and transfers them down to those Frame walls below. However, if the top of the Gravity walls were sloped, Line and Point loads on such gravity walls were mishandled while transferring them to Frame walls below.
Effect: Line and Point loads modeled on sloping Gravity walls supported by Frame walls below were lost, and not applied to the Frame walls. The error did not occur if the Gravity walls were not sloping.
RAM Steel Beam
COMPACT CHANNELS AISC 360: Some compact channel sizes designed according to AISC 360 were flagged as slender and skipped during optimization.
Effect: During optimization some compact channels were erroneously tagged as slender and skipped. Some frozen compact channels were flagged as slender and not designed. Previously these channels were designed correctly.
VIEW/UPDATE DEFLECTION INTERACTION: The deflection interaction value displayed in the View/Update dialog box was incorrect for beams that were modeled as composite beams but had to be designed non-compositely because the required number of studs wouldn’t fit.
Effect: While designs and reports for composite beams designed non-compositely were correct, the value displayed for the deflection interaction in the View Update dialog box was incorrect.
BEAM OPTIMIZATION*: During optimization ASD 9th and LRFD 3rd Edition may have “selected”, as optimum, beam sizes that actually failed, and did not continue to investigate heavier beams until the correct size was found.
Effect: While optimizing sizes using the ASD 9th and LRFD 3rd Edition codes, some beams failing the pre-composite or non-composite checks were presented as optimized designs. Even though the size was not actually the size that should have been selected as the optimized size, the Failed interactions for the selected beam size was correctly reported and the color coding correctly indicated as failed. The failed beams could only be corrected through user size assignments. This could be somewhat common for multi-segmented beams and LRFD beams governed by 1.4DL combination.
COMPOSITE CELLULAR AND CASTELLATED BEAMS: In View/Update for composite cellular and castellated beams, the number of studs could not be modified and analyzed.
Effect: User could not assign the number of studs to be used, the program always only used the optimized number of studs.
C-BEAM CAMBER: When C-Beams (formerly called SMARTBEAMS) are optimized, the design gives an acceptable range of Spacing or Diameter (for Cellular) and a range of Phi (for Castellated). This means that there is a corresponding range of member depths and section properties, and as a result, a range of deflection values. The program reported camber consistent with the worst strength interaction rather than the worst deflection encountered.
Effect: Report error only. The reported camber may have been inconsistent with the reported components of the worst deflection encountered. The reported camber was correct for the hole configuration associated with the worst strength interaction value, but was not necessarily correct for the hole configuration that caused the greatest deflection.
RAM Steel Column
USER-SPECIFIED COLUMN BRACING*: When a new column was added in the Modeler that did not fall on an existing column line, or if a new story was added, any user-assigned column bracing was being cleared unnecessarily.
Effect: User-assigned bracing of columns (done using the Assign – Bracing command) may have been cleared and the program then used the program-calculated bracing of columns. Although usually conservative, this could result in unconservative designs if the user specified that the column was unbraced (but that information got cleared) at a level that the program determined was braced.
AS 4100-98 TENSION AND BENDING*: An incorrect gamma may have been used for columns under combined tensile and bending forces.
Effect: Columns under tensile and bending loads may have passed designs when an incorrect gamma value of 1.4 was used, when they should have failed using the correct higher gamma value per the requirements of AS 4100-98 Section 8.3.4.
AS 4100-98 COMPRESSION-ONLY: Some compression-only columns were indicated as failed for exceeding delta-b > 1.4, even though the provisions of section 4.4.2.2 were not applicable.
Effect: The provisions of section 4.4.2.2 were erroneously applied to compression-only columns. Some compression-only columns were not designed due to the erroneous application of the provision.
AISC 360-05 and -10 AXIAL CAPACITY*: In the Controlling Axial Column Load section of the Gravity Column Design report, the value listed for axial capacity Pn was only based on Section E3. That is correct for most columns, but if the axial capacity should have been controlled by some other Section of Chapter E, the reported value was incorrect.
Effect: In rare cases the axial capacity listed in that section of the report may have been incorrect. Note that the capacity used and reported in the Controlling Combined Column Loads section was correct, so there was no impact on design except for the following condition: if Pr/Pc was less than 0.2 (so that Equation H1-1b is specified), it is possible that Pr/Pc listed in the Controlling Axial Column Load section controlled rather than Eq (H1-1b) (since in that equation Pr/Pc is divided by 2); the design would potentially be unconservative if that value was incorrectly calculated as described. It was extremely unlikely that this set of conditions would actually result in an unconservative design.
RAM Concrete Analysis
SLAB SELF-WEIGHT MISSED*: Slab self-weight was not determined and applied to two-way slabs.
Effect: Slab self-weight was missing from the slab Dead Load.
RAM Concrete Beam
ACI TRANSVERSE HOOP SPACING*: If there was more than one layer of flexural reinforcement and the bar sizes varied between those layers, the maximum transverse reinforcement spacing (which is based on the flexural bar diameters, see ACI 318-11 Section 21.5.3.2) for the seismic provisions may have been incorrect, failing to consider all of the bar sizes in all of the layers; the program only considered the bar sizes in the first reinforcement layer, dismissing the bar diameters of the other reinforcement layers.
Effect: Potentially incorrect (unconservative) hoop spacing.
ACI GRAVITY BEAM TRANSVERSE REINFORCEMENT*: Gravity beams in structures assigned to Seismic Design Category D, E, or F, for which the moments and shears due to the induced displacements have not been calculated, are required to conform to ACI 318-14 Section 18.6.5, according to Section 18.14.3.3 (or analogous clauses in earlier codes). The shear force Ve was not considered as required in Section 18.6.5.1, and Vc was not being set to 0.0, as required in Section 18.6.5.2.
Effect: Potentially inadequate transverse reinforcement in gravity beams in Seismic Design Category D, E, or F.
RAM Concrete Column
ACI SMF TRANSVERSE SEGMENT LENGTH*: Requirements for ACI 318-11 clause 21.6.4.1 were incorrectly applied.
Effect: The length lo for transverse reinforcing may have been inadequate when ACI 318-11 21.6.4.1 applied.
ACI TRANSVERSE SPACING IN SMF COLUMNS: The requirements for reinforcement spacing beyond the length specified in ACI 318-11 21.6.4.1 in SMF columns was being calculated according ACI 318-11 21.6.4.4. However, those segments should be checked per 21.6.4.5.
Effect: A conservative spacing of transverse reinforcement through the central segment of SMF columns may have been specified.
ACI TRANSVERSE REINFORCEMENT*: When determining Vc according to clause 21.6.5.2 of ACI318-11 (or earlier), the maximum value of the axial load on the column from all load combination, rather than the axial load for each load combination, was used against the prescribed limit. This may have led to Vc not being set to zero for some load combinations as required by the code.
Effect: Transverse reinforcement may have been inadequate.
SQUARE COLUMNS*: In very rare instances, for some square symmetrically reinforced columns where a critical point was very, very close to the axis, there could have been differences between the interaction curves at orientation angle 0 versus 90.
Effect: In a very rare case the interaction curve data used in design may have been incorrect.
AS 3600-09 COLUMN DESIGN*: When AS 3600-09 was selected as the design code, in certain instances the program was using some AS 3600-01 code requirements to design columns.
Effect: Incorrect AS 3600-09 column designs.
EUROCODE DESIGN: When using the EC2 design code, the critical major and minor shear forces (VEd) reported in the report were not the actual critical shear forces used in design. This was a reporting only error; the correct shear forces were used in the design and could be viewed in the V/U dialog.
Effect: Report error only, the values reported for shear were incorrect.
CHINA GB50010 SHEAR: The shear forces for major and minor axis for the Chinese design code (GB50010) were reversed in the View/Update dialog. This was a reporting only issue; the correct forces were used in the design.
Effect: Report error only, the shear values displayed in View/Update were reversed.
COLUMN CURVES: In rare instances, when designing a column to the ACI design code, the column PMM curve in the View/Update dialog might have displayed incorrectly for particular angle or angles. The cause of this was an incorrect interpolation due to points on the curve that happened to be in very close proximity. This may have also lead to unexpected capacity design failure.
Effect: In rare cases column designs may have incorrectly been listed as failing, and the PMM curve diagram may have been incorrect.
RAM Frame – Analysis
OVERLAPPING SURFACE LOADS ON TWO-WAY DECKS*: The program may have missed gravity loads on two-way decks when there were overlapping surface loads.
Effect: Gravity loads due to overlapping surface loads on two-way decks may have been missed in RAM Frame.
AS/NZS 1170.2:2002 WIND LOADS*: When wind speeds were entered in metric or SI units, the values were not correctly stored, resulting in incorrect wind forces.
Effect: Incorrect wind forces. Note: to correct this error in existing models it is necessary to re-enter the AS/NZS Load Cases wind speed values.
CENTER OF RIGIDITY REPORT: The report showed values for center of rigidity locations for semirigid diaphragms. Center of rigidity calculations are only valid for rigid diaphragms.
Effect: Invalid values were shown for diaphragms that were designated as semirigid.
BUILDING STORY SHEAR REPORT: If the Building Story Shear report was generated only for a few selected response spectra cases, the reported dynamic shears were not correct.
Effect: Incorrect dynamic load case shears were reported if the report was generated for only some of the dynamic load cases; if all dynamic load cases were included, the reported dynamic shears were correct. This was a report error only, and did not affect designs.
INCORRECT REACTIONS REPORTED IN ANALYSIS LOG REPORT: For models with walls that terminate at a level other than the lowest level (such as for buildings with partial basements), the Analysis Log report showed reactions in X and Y directions for gravity load cases. Since gravity loads are only applied in vertical directions, no reactions for X and Y directions are expected. For such models, the program inserts foundation nodes under the wall, but the report failed to consider foundation reactions from such nodes.
Effect: Report issue only.
RAM Frame – Steel Standard Provisions
AISC 360-10 SECTION H1.3: The provisions of section H1.3 were erroneously applied to members subjected to both tension and compression.
Effect: Potentially conservative design of tension members. Members subjected to tension were checked for the provisions of section H1.3 when such provisions only apply to compression members.
SLENDER MEMBER WARNING*: In some cases slender members were not flagged as such for the AISC 360, AS 4100 and CAN S16-09 codes.
Effect: Sizes may have been indicated as acceptable even though they exceeded the slender member limits (e.g., KL/r > 200) for some load combinations.
RAM Frame – Steel Seismic Provisions
BUCKLING RESTRAINED BRACED FRAME REPORT: User-assigned Stiffness Modifiers (SM) were not correctly reflected in the BRBF Summary report. When the system units changed from SI or Metric to English, the reported Keff was incorrect.
Effect: The BRBF Summary Report showed an incorrect effective stiffness (Keff) for braces where a stiffness modifier was assigned. Furthermore, for reports where the system units was metric or SI, no unit conversion was performed on the reported Keff values. This was a report problem only, the code checks for all BRBF braces were correctly performed.
RAM Foundation
BRACE FORCES ON FOUNDATIONS*: When a frame column and a brace frame down to the same location on a foundation, in a very rare case the node associated with the bottom of the brace may be different than the node associated with the bottom of the column. If the vertical distance between those two nodes varied by more than the strict tolerance used by the program the forces from the brace were not imposed on the footing.
Effect: In a very rare occasion, foundations supporting both a column and a brace at a point may have been designed only for the column load. The tolerance has been liberalized to ensure that this no longer occurs.
RAM Concept Link
WALLS NOT EXPORTING: Walls with 0" slab edges or slab opening offsets were not imported into RAM Concept from RAM Structural System.
Effect: Walls on perimeter of floor or at openings, with 0” edge offsets, were not included in the data exported to RAM Concept.
ISM / Structural Synchronizer
Several ISM defects were corrected, including several that caused the program to crash when creating or updating an ISM repository. Errors that caused models created from a repository to have problems analyzing in the RAM Structural System were also corrected. The more notable corrections are noted here.
PILE CAPS: The inclusion of pile caps with certain orientations caused the ISM process to crash.
Effect: Program crash during creation of ISM file. Pile caps now successfully export to ISM.
DUPLICATE COLUMNS: When creating a new repository, duplicate columns may have been generated.
Effect: Duplicate columns in the ISM model.
COLUMN HOOKS: Edge column longitudinal reinforcing bar hooks extended out of the concrete.
Effect: Bar hooks extended beyond concrete edges. Now all column longitudinal reinforcing bars end hooks are oriented towards the center of the column.
Appendix A
Technology Preview – Analytical Insights
Information on Analytical Insights can be found at this link: Appendix A Analytical Insights.
Appendix B
Technology Preview – RAM Structural System data available through SQLite
Enabling the Feature
This feature is now automatically available. In the previous version (v15.04) it was necessary to modify the ramis.ini file in order to enable it. That is no longer necessary. If you modified the ramis.ini file previously by adding the line WriteDataToExternalDatabase=1, you can now delete it.
Description
Two SQLite files are generated by the RAM Structural System. A file with geometric data can be created by invoking the Post-Processing – Export Geometry to SQlite command in RAM Manager. The second file is created in RAM Frame as part of the Analysis. To write the analysis results to SQLite, select the check box at the bottom of the dialog that says "Write Results to SQLite database."
These files are part of the model. They are initially written to the working directory and then saved into the .rss file.
A report generator that reads the SQLite database tables and creates reports in Excel has been added to the RAM Manager. The commands to run the viewer are located under the Post-Processing menu. The report generator can be run in two different ways:
I AM NOT ABLE TO ANALYSE AND DESIGN THE CURVED BEAM. NO DEFECTION, SHEAR OR BENDING OR TORSION DATA IS GIVING.
WHAT ALTERNATIVE DO I HAVE?
| Applies To | |||
| Product: | RAM Frame Analysis | ||
| First Affected Version: | |||
| Found in Version: | 15.05.00 | ||
| Fixed and Released in Version: | |||
| Area: | Analysis | ||
| Issue #: | 739116 |
A RAM Container crash occurs during the RAM Frame Analysis when the program is "Reading Model Data":
A section label for concrete columns (RAM Modeler - PropTable - Column Sections) shares the same name as a section label used for concrete beams defined as T-sections (RAM Modeler - Prop Table - Beam Sections. See example below:
We are working on a fix for this issue. In the meantime, use different section labels for the beam and column.
| Applies To | |||
| Product(s): | RAM Concept | ||
| Version(s): | Various | ||
| Environment: | N/A | ||
| Area: | Analysis | ||
| Original Author: | Bentley Technical Support Group |
This tech note discusses how to determine the Creep Factor and Initial Load Application for the AS 3600 design code. RAM Concept uses the ACI 209 model for creep and shrinkage. The creep and shrinkage parameters outlined in AS 3600 need to be modified to fit this model.
In general, the final (30-year) creep value after being modified by all appropriate adjustment factors should be input as the creep factor.
AS 3600 references a creep coefficient, which is defined as the ratio of creep strain to elastic strain. The creep factor in RAM Concept is defined as the ratio of total strain (elastic strain + creep strain) to elastic strain, or 1 + creep strain/elastic strain. The creep factor in RAM Concept then is equal to 1 + creep coefficient.
For AS 3600, the input creep factor is determined as follows:
See “Creep Coefficient Correction Factors” for more discussion on Steps 2 and 4 above.
AS 3600 uses the correction factors k2, k3, k4, and k5 to convert the basic creep coefficient to a design creep coefficient at any time. See Equation 3.1.8.3 in AS 3600-09.
Factor k2 should be based on a 30 year time after loading.
Factor k3 is a maturity coefficient that accounts for the initial load application. This parameter is analogous to the parameter in ACI 209, which is automatically accounted for by RAM Concept. A correction factor should be calculated based on the discussion in the Initial Load Application section below to calibrate the ACI 209 model used by RAM Concept to match the AS 3600 model.
Factor k4 accounts for environmental factors and will vary from project to project.
Factor k5 is a modification for high strength concrete and is a function of the concrete strength.
ACI 209 is based on a 7-day initial load application time, while AS 3600 is based on a 28-day initial load application time. The Initial Loading Application value that is input into RAM Concept should be based on the construction and shoring schedule of your project and not the standard values specified in the design code. For example, it is common in the United States for formwork to be removed anywhere between 3-7 days and this is what should drive the input of the Initial Load Application value in RAM Concept.
ACI 209 uses a modification factor to account for initial load application times other than 7 days. This factor is automatically determined by the program and should not be incorporated into the input creep value. In AS 3600, the k3 correction factor accounts for the initial load time. A correction factor should be applied to the input creep factor to match the k3 factor to the age coefficient in the ACI 209 model.
In the plot below, the red line represents the equation for the maturity coefficient in ACI 209. The blue line represents the equation for the k3 factor in AS 3600. The green line is the ratio of the coefficient in AS 3600 to the coefficient in ACI 209 and represents the calibration factor that should be applied to the input creep factor to calibrate the ACI 209 model to the AS 3600 model.
For a single load application time, the calibration factor determined from the green line is easily determined. However, most real load histories are more complicated and include many loading/unloading times. For these more complex cases, the initial load application time is generally the most influential on creep deflection and the factor associated with this time from the green line plotted above should be used. For example, if the actual initial load application time is 7 days, then the correction factor is between 1.4 and 1.5.
Determine the creep factor for a 32 MPa, 200 mm concrete slab in a temperate inland factor environment. Initial loading time is 28 days.
The basic creep coefficient from Table 3.1.8.2 is 3.4.
k2 = 1.2 (see Figure 3.1.8.3(a) at 30 years after loading)
k4 = 0.6 (for temperate inland environment, see 3.1.8.3)
k5 = 1.0 (f’c < 50 MPa, see 3.1.8.3)
calibration factor for k3 = 1.3 (from green line in calibration plot above for time of 28 days)
Creep Factor = 3.4*1.2*0.6*1.0*1.3 + 1 = 4.18
The initial loading time is 28 days. The Initial Load Application should be defined as 28 days in the Load History/ECR tab of the Calc Options dialog.
RAM Concept Load History Calc Options
| Product(s): | RAM Structural System | ||
| Version(s): | 10.0 and later | ||
| Area: | File |
A RAM Structural System model file (e.g. filename.rss) is literally a Zip file and within any .rss file you should find many component files of the same name with a wide range of extensions including (but not limited to) .b3d, .ram and .uid. These files are extracted from the model file and put into the working directory when opened in RAM Manager (in older versions of the program all of these files were simply saved together in the model directory). In some cases a zip repair utility can be used to open a .rss or .backup file that won't otherwise open.
For this reason the working directory should always be on the local drive and in a place in which the “user” has administrative rights. It’s also important for the user to have the rights to add, modify and delete files in the model directory.
Note: the working directory is set the first time the program is run, to confirm or edit the working directory location go to C:\ProgramData\Bentley\Engineering\RAM Structural System and double click the Ramis.ini file (c:\windows\ramis.ini prior to version 14). This should bring up the Ramis.ini file in Notepad (or other text editor). Look for the line that begins
working=path to working directory.
You can edit this path to the working directory here. Spaces are allowed as are references to mapped drives, but for the reasons mentioned above, a local drive should be used.
Also in the [Directories] section you will find the paths for other installation directories like the Tables folder where the program looks for all the tables and the default reports directory for saved reports.
For more information on the contents of the Ramis.ini file, refer to the RAM Defaults Guide [TN] and the RamSS Installation FAQ.
Regretfully Ram SS models are not backward compatible. Typically with each major release there are changes in the model data base format. Once models are converted to the new version they can no longer be used in prior versions.
When a model is converted a backup of the original file is automatically created in the same folder with the same name and appended with the original file version, e.g. MyFile_Orig_14_7.zip, in case there is any need to revert to the prior version.
Note, though version 14.06.01 is generally considered a minor release, file conversion from version 14.06.00 is required. See the 14.06.01 Release Notes for details.
If the listed user really is in the file, they need to exit the program normally to release the model so that you can open it (RAM SS models do not allow for concurrent use).
If that user is not currently in the file or unavailable, you should navigate to the directory where the model is saved and look for a file of the same name with the file extension “.usr”. This is a lock file that was created when the user last accessed the model. The .usr file is normally deleted when the model is closed, but if the program terminated irregularly, the file might persist. Simply delete the .usr file and the .rss file can then be opened.
If you select the “Most Recent Database” you are telling the program to reload the files from the working directory which should be the same as they were just before the crash. In such cases, we suggest that you immediately use the file – save-as feature to turn this into a new model file.
Clicking “Backup Database” deletes the working files and restores the files from the saved model whenever it was last saved. “Cancel” leaves everything alone. If your not sure when the last save occurred, click cancel and then check the modified date of the model file through an explorer window before returning to pick either option.
Starting with version 14.06 an additional backup file is created for models that crash and are then re-opened. A copy of the rss file with the extension .ssr is created if you reopen a model that is already expanded to the working directory indicating a previous crash or incomplete closure. Like the .backup file, the .ssr file can be renamed with a .rss extension to restore that version of the file.
There are two situations where this message might appear. The first is a restriction to the working directory or the model directory. The user needs to have the rights to add, modify and delete files from both locations (preferably administrative rights). See above for more on the working directory.
The second problem is a corrupt or partial model file. If the model file is missing any of the critical component files it will not open correctly and the same message will appear. To investigate, rename the model file, changing the extension form .rss to .zip and double-click it to see what inside. You should see a series of files all with the same name but with a wide range of extensions including (but not limited to) .b3d, .ram and .uid. When a model file does not contain a complete set of component files it is unusable. It is a mystery what causes a file to become this way, but it seems that something must have interrupted the save process. A virus scanner may also be responsible.
At this point the backup file should be used, see below.
The error may be caused by an installation issue with a database component included with RAM Structural System. Removing and reinstalling the component may resolve the issue. To do this, perform the following steps:
See also [[Unable to find the requested .NET framework data provider]]
Yes, in the directory where the model file is saved, there should be another file of the same name with the extension, “.backup”. Rename this file something.rss (you won’t be able to use the same name of the original model file unless you move or rename it first). The backup file should be a complete version of the model from the previous time it was saved. If your not sure when that was, simply check the modified date.
Note: when backing up your own files, it is only the .rss model file that you need to save. When restoring backup files or old files from a backup CD or tape, make sure the files are not read-only. If you attempt to open a RAM model that is read-only, you will get another warning, “Failed CopyRssFileToWorkingDir:…”, “Failed DeleteRssInWorkingDir:…”, or “File error 2,6”.
A RAM Structural System model (file.rss) is already a compressed zip file, but the size of that file can become quite large, especially when the analysis and design results are saved with the file. In RAM Manager under the File menu is an option to ZIP the model. When zipping models using that command you will have the opportunity to purge the model of some unnecessary results (which can be regenerated later just by running the file again). The optional results are:
[[Unable to find the requested .NET framework data provider]]
RAM SS File-Open Troubleshooting [TN]
| Applies To | |||
| Product(s): | RAM Elements; Ram Connection | ||
| Version(s): | All | ||
| Area: | Licensing - Technical | ||
| Subarea: | Ram Connection | ||
When earlier versions of RAM Elements were opened,s a RAM Connection license was also used. This behavior may not be desirable for the following reasons:
By default, RAM Elements release 13.00.03.45 and earlier enables connection integration features within the program if the RAM Connection for RAM Elements component is installed. Starting with Ram Elements 13.02.00.99, which uses trust licensing, we changed the default behavior so that users have to opt-in to utilizing Ram Connection. If a RAM Connection license is available, the program will retrieve a license automatically and add buttons for Connections, Bolts, and Welds to the Databases ribbon. If the integration features are not needed, this behavior can be disabled.
If an engineer only occasionally models connection data within RAM Elements, the integration can be disabled from within RAM Elements itself and turned on only when needed.
Ram Elements V8i instructions
RAM Elements will disable the RAM Connection integration features and will no longer automatically retrieve a license or log usage for RAM Connection.
Ram Elements should then be restarted.
RAM Elements CONNECT Edition instructions
4. Uncheck the option for Ram Connection to "Use a license in each session"
For RAM Connection 8.0 only, the integration component, which is called RAM Connection for RAM Elements, is installed separately. If an engineer will never model connections within RAM Elements, uninstall the RAM Connection for RAM Elements component from the Add or Remove Programs (Windows XP) or Programs and Features (Windows Vista/7/8) control panel. RAM Elements will then retrieve a license only for itself regardless of the license setting in the Configuration dialog. Users of RAM Connection 7.3 and earlier should use Option 1 to disable integration.
If you want to use Ram Connection features temporarily, click the Start... button in the License Configuration - Ram Connection area.
If you alwayswant the Ram Connection features to be available in Ram Elements then check the box to "Use a Ram Connection license in each session".
In some cases Ram Elements users must still click Start during each session to enable the Ram Connection features. This was be fixed with Ram Connection 10 and later.
[[RAM Connection 11 and Ram Elements]]
[[RAM Connection is installed, but the Connection button fails to appear in RAM Elements]]
[[RAM Connection v9.0 and RAM Elements]]
[[SELECTsupport TechNotes and FAQs]]
| Applies To | |||
| Product(s): | RAM Elements; Ram Connection | ||
| Version(s): | 13.04.01.208 and later | ||
| Area: | Licensing - Technical | ||
| Subarea: | Ram Connection | ||
Ram Connection for Ram Elements has been installed, but the connection tool bars and features are missing from Ram Elements.
RAM Elements will enable the RAM Connection integration features.
If you don't want to use a Ram Connection license or want the Ram Connection features to be available in Ram Elements then uncheck the box that indicates to "Use a Ram Connection license in each session".
Ram Elements should then be restarted.
[[Enable or Disable RAM Connection for RAM Elements]]
[[RAM Connection is installed, but the Connection button fails to appear in RAM Elements]]
[[RAM Connection v9.0 and RAM Elements]]
The TechNotes and FAQs in this section cover various topics that pertain to RAM Connection. Use the navigation tree on the left to browse or the popular links below.
The technotes and FAQs in this section cover various topics that pertain to installing Ram Connection or using it the first time.
The TechNotes and FAQs in this section cover various topics that pertain to RAM Elements. Use the navigation tree on the left or the popular links below to browse.
| Product(s): | RAM Elements, RAM Structural System, Ram Concept, STAAD.pro; MultiFrame; Microstran | ||
| Version(s): | Any | ||
| Area: | Analysis |
A typical 3-dimensional Finite Element analysis of a structure requires that every node must be stable in all 6 degrees of freedom (TX, TY, TX, RX, RY,RZ). This is achieved by specifying fixity conditions for the columns, beams and braces spanning to a given node or through nodal restraint. While many programs can analyze a structure using fewer degrees of freedom, for this discussion all 6 are assumed to be active.
There are many discussions related to FEA online and whole courses devoted to the topic, but the purpose of this article is merely to show by example a few of the most common causes of instabilities in structural models. The rules apply to RAM Elements (aka RAM Advanse), RAM Frame, RAM Concrete or STAAD.pro as well as other FEA applications. The images and examples below are taken from RAM Elements where a light blue circle indicates a hinge, or member release, at the end of a member. A translational restraint is depicted as a triangle on rollers and a rotational restraint is a "T".
Take the case of a single member fixed at the base for all 6 DOF similar to a flagpole. This structure is stable, except that the free end of member away from the support is hinged or released for major axis bending. As a result, node 2 can spin about the global z axis.
For some applications, this type of "nodal instability" will terminate the analysis. For other applications, a small stiffness may be automatically assigned to the z axis rotational stiffness of the node and you may only get a warning, so long as a moment about the z axis is not applied directly to node 2. This would cause infinite rotation of the node and should terminate any analysis.
The same situation often occurs for a beam with a cantilever, where the cantilever beam is the only member connected to the node at the tip. In short, the free end of any member, where that member is the only member in the model connected to a particular node should never be released.
When multiple members frame to a single node, it is acceptable to release some, but not all of those members. If the beam, column and brace are all released at the same node, then the problem is the same as case 1 above. At least one of those members should be fixed ended. In most situations, it is the column top that should remain fixed to the node.
In this case we have a fixed ended beam setting on two columns, both of which are released at the top node. This case differs slightly from Case 2 because the nodes are fixed to the beam and not themselves instable. The problem is that the beam along with both top nodes can spin as a group on top of the columns similar to a log on water. This is an example of why it is usually better to keep the tops of the columns fixed and release the beams.
It's hard to envision a realistic connection that allows a member to spin or swivel, but most FEA application do allow member torsional releases. A general rule is to leave the member torsion fixed except in a situation where member rotation really is free. The most common problem occurs in a chevron brace configuration where the beam is two finite elements. If each beam half is released in torsion, then the node at the top of the braces is instable.
Often it is desirable to analyze a 2-dimensional frame using a 3-dimensional analysis. In some applications there is plane frame option that can be used to ignore the deflection out of plane (e.g. z axis) or rotation about the other axes, but if not, the frame can generally be stabilized one of two ways.
The same situation often occurs in RAM Frame when no rigid diaphragm is used. This can leave the model with several, isolated, 2D frames in space with no connection between them. If the frames are pinned at the base then they can fall over and an instability results. Fixing the base of the frames against out-of-plane rotation is generally the solution to this problem, though connecting the frames together with lateral members or some other simulation of a diaphragm is also possible.
A certain number of nodal restraints are always required to keep the structure as a whole from moving. Another common case is one where a shell or mat foundation is supported by a series of vertical springs. While that is stable in relation to vertical loads, some mechanism must be provided to keep the mat as a whole from sliding around like a skateboard. This is generally achieved through the use of horizontal springs in addition to the vertical springs, or by restraining the translation of a node (or line of nodes) along the edge of the structure.
This is a common problem in Ram Concept if a vertical resistance area spring is the only support for the structure. When there are no lateral loads, you might get away with providing an area spring with only vertical stiffness, but when there is any external load applied in the plan directions, some resistance to sliding must be incorporated into the model. Ram Concept also has an option under Criteria - Cal options to "Auto-stabilize structure in X and Y directions" which is another option for structures with vertical loads only.
In most building type structures there is a horizontal diaphragm that ties the frames together and prevents in-plane deformation of the plan. This is typically modeled using a rigid floor diaphragm. The diaphragm constraint forces the nodes of the floor to move together preventing the plan from racking for example.
In space frame models where no rigid diaphragm is modeled (perhaps because the roof is sloped), there must be some other mechanism to keep the plan from racking. This is generally achieved by providing diagonal members in that plane. Fixing the minor axis of the beams in the plan is another approach. Think of this like creating a Vierendeel truss in plan. Using shell elements is another option, though the interaction between the shells and the members is not always desirable.
When a model utilizes non-linear members or springs most FEA applications iteratively solve for each load case and load combination. On each iteration, if a tension-only member is found to go into compression, that member is thrown out of the analysis and a new iteration is started. If too many of the members go into compression, the frame or structure as a whole can become instable.
There are a couple of ways to effectively deal with such a situation
There are cases where a structure might be perfectly stable under a first-order analysis, but as the analysis incorporates P-Delta effects the deflection is amplified and instability can result. Different applications handle P-Delta analysis in different ways, but there are usually controls for the tolerance required for P-Delta convergence. Increasing the tolerance often leads to a solution, but some structures may have to be stiffened in order to complete a P-Delta analysis on all load cases.
Structural Product TechNotes And FAQs
STAAD.Pro Instability And Zero Stiffness
[[Microstran Modeling Tips]]
Links here
| Applies To | |||
| Product: | RAM Connection for RAM SS | ||
| First Affected Version: | 11.01.01.240 (15.05.00) | ||
| Found in Version: | 11.01.01.240 (15.05.00) | ||
| Fixed in Version: | |||
| Environment: | x32 and x64 | ||
| Area: | Import/Export | ||
| Issue Number: | 7 |
If RAM Connection CONNECT Edition version 11.01.01.240 (x32) is installed, it cannot be launched from Ram Structural System CONNECT Edition (x64) via the Ram Manager menu or button.
A new defect to be corrected in the next build.
Problem to be corrected in the next build after 11.01.01.240. Until then, if integration with Ram Structural System is required, uninstall Ram Connection 11.01.011.240 and reinstall an older version (e.g. 11.01.00.227).
Links here
