Overview

These section databases are currently implemented in the current version of OpenTower Designer (build 10.1.0.2):

• United States:
  • AISC Imperial:
    • 7 Edition (ASD)
    • 9 Edition             
    • 13 Edition
    • 14 Edition
  • AISC Metric:
    • 13 Edition          
    • 14 Edition
  • API 5L
• Europe:
  • CEN:EU 19-53:CORUS
  • CEN:BS EN 10210-2:2006
  • CEN:EU 19-57:MITTAL
• India:
  • BIS:808 : 1989

Note:  In the next version of OpenTower Designer, which should be released in June 2021, Australian sections and materials will also be implemented.

Design Software for Communication Towers

OpenTower Designer performs comprehensive design and analysis of various types of communication structures such as tapered monopoles, stepped poles, 3-legged or 4-legged self-supporting and guyed towers. OpenTower helps engineers to generate the physical model using parametric setup wizards and categorizes the panels/sections, legs, horizontals, and bracing members with orientations without manual intervention. The structure can easily be edited to achieve the desired shape and configuration.

Visit the www.opentower.com for additional information on this product.

OpenTower is the next generation of Bentley's Tower product and users of that product will find OpenTower a familiar improvement.

LEARN

View STAAD(X) Tower learning paths on Bentley's LEARNserver.

Download

You can download the latest version of OpenTower from Bentley's OpenTower Designer.

Support

Visit [[OpenTower TechNotes and FAQs]]

Related

Browse related content tagged: STAAD(X) Tower

STAAD(X) Tower TechNotes and FAQ's

[[STAAD(X)]], [[STAAD.Pro]], [[MStower]]

Problem Description

I am unable to run OpenTower Designer as an user; it does not start and no errors are reported. I can run it as an administrator.

Response

OpenTower Designer requires read and write access to the Programs folder.

Please ensure that as a user you have read and write access to the following folders.

C:\ProgramData\Bentley

Also, please check if your machine has the following Microsoft Redistributables installed:

Note: It’s recommended to run the application as “Run as Administrator”

Tower design re-imagined

Structural modeling, analysis, and design solution for communication towers

We are proud to announce the release of OpenTower CONNECT, a leading structural solution for telecommunication towers. This purpose-built application captures real-life analysis workflows, including modifications, multiple scenario evaluations, foundation checks, and connection designs. It can connect with equipment databases to automatically generate wind and seismic loadings, analyze the structure and produce custom reports. The application’s advanced graphics offer a realistic view of the tower as modeled, including 3D rendering of equipment and feedlines on the tower. The program is offered through’s Bentley’s consumption-based visa licensing program and known as OpenTower Comms Visa.

[[STAAD(X) Tower]] is now OpenTower. OpenTower is the next generation of Bentley's STAAD(X) Tower product and users of that product will find OpenTower a familiar improvement.

Flexible and extendable architecture

OpenTower was developed with an open architecture. Considering changing business trends on modifying existing structures, the application is designed to work with external catalogs and libraries, which can be edited and extended throughout the lifecycle of tower management and re-analysis.

OpenTower includes comprehensive databases, such as appurtenances catalog, bracing library, and truss-leg library. A custom tower catalog is provided for built-up sections, typically used for reinforcing towers. This catalog can be extended by adding new sections and new section profiles. User-provided table (UPT), is an innovative method to create and use user-defined materials, sections, and appurtenances.

With state-of-the art technology and graphics, OpenTower is designed for its openness and user-friendliness.

Increased Modeling Efficiency with Automation and Best-Practices

Engineers can now model lattice towers faster than ever using physical model generation utilities thorough parametric wizards. This includes automatic orientations of all members. It is a physical modeling system, where geometry is defined as a combination of multiple panels, starting from the top.

Discrete and linear appurtenances can be easily attached and viewed through built-in catalogs and an intuitive user interface. OpenTower automatically generates wind, ice, and seismic loads based on TIA 222- Rev F, Rev G, and Rev H standards along with ASCE 07.

The application was designed by practicing engineers and encompasses engineers’ desired workflow and best practices. All the inputs were cleverly structured and screens were reimagined to optimize your work. Discrete appurtenances can be attached through mounts, and feedlines are provided in reference to linear attachments, such as ladders and banjo brackets.

Advanced Capabilities

A OpenTower model essentially becomes a living history of a tower’s lifecycle management through its modification layer and scenario analysis capabilities. The application’s multilayered approach to separate modification layers from the base model, enables users to combine installed model with hierarchical proposed modifications. All modifications are saved for future use.

The application separates loading layer from geometry layer. Users can create any number of load definitions, groups, and configurations with appropriate classifications. A loading layer can then be combined with a geometric layer to create an analysis scenario. Users can analyze and compare as many scenarios as needed to deduce the optimum configuration.

Realistic Graphics and precision modeling

OpenTower adopted “Wysiwyg” philosophy. It promotes precision modeling and offers many powerful capabilities to achieve it. All section profiles, including built-up sections like split-pipe are drawn to scale with appropriate rotation of its major and minor axes. Any object, including discrete and linear appurtenances can be clicked to review its properties. Feedline Tool helps to position the feedlines along the height of the tower by forming and moving feedline stacks on a grid system. The application can automatically form clusters and calculate the effects of shielding. Visualization shows realistic 3D graphics of all modeled equipment on the tower along with geometry.

Powerful Results and Diagrams

OpenTower provides an exhaustive set of post-processing features that includes results and diagrams. It renders leg compression curves, deflection, tilts, twists, axial forces, moments, torsion, and stress diagrams along with dynamic browsing facility for member forces and member stresses at any point of the cross-section on any member at any location for any load case. It displays tables for member-end forces, joint displacements, and support reactions. Users can customize report format through intuitive report generator and export to various formats, including PDF and Microsoft Excel spreadsheets.

Support for Legacy Software and Interoperability

OpenTower can import any RISA Tower or tnxTower model (.eri files). The application generates a STAAD.Pro file that can be used for advanced analysis, like dynamic and buckling analysis, as well as flexible Mat foundation design.

Foundation Design

Engineers can now easily design/check tower foundations with program’s built-in foundation design functionality. It automatically iterates through support reactions for all load combinations to find the critical load combinations for all possible design criterion, including serviceability and ultimate design. Current version of the program supports, pad &pier (isolated) foundation, block foundation, drilled pier foundation, and guy anchor foundation. It greatly increases tower design efficiency.

OpenTower AT-A-GLANCE

• Physical modeling with bearing angle for square and triangular self-supporting and guyed towers
  • Enhances productivity through faster model generation wizards
  • Models can be edited parametrically, which increases efficiency and saves time
  • Automatic member orientation enabling precision modeling
• Flexible libraries, catalogs, and user-provided- table
  • Increases productivity by providing a library of reusable bracing patterns and truss legs
  • Custom tower catalog for commonly used built-up section profiles and materials
  • Extensive database of mount, discrete, and linear appurtenances
• Realistic 3D graphics
  • Tower and all equipment are drawn to the scale
  • Smart input screens for precise position of equipment with azimuth and offsets
  • Feedline tool for stacking and positioning of feedlines along with cluster formation
• Tower modification, scenario analysis
  • Automatic generation of wind, ice, and seismic load cases for tower structures and external attachments as per TIA-222-F, TIA-222-G, and TIA-222H standards
  • Hierarchical modification layers and scenario analysis for “what–if” scenario investigation and data management
• Analysis- linear static, P-Delta, nonlinear cable, and modal analysis
• Post-processing features includes joint displacements, member forces, stresses, support reactions, leg compression, deflection, tilt, and twist results in terms of diagrams and tables
  • Enables the user to have a detailed insight of the analysis results
  • Helps to plot multiple post-processing diagrams for a selective set of physical members for complex structures
• Foundation, connection, and member design as per TIA-222-F, TIA-222-G, and TIA-222-H standards
  • Integrated foundation design saves time and reduces errors
• Customizable, user-friendly exhaustive report-generation facility
  • Create all exhaustive complete report straight from the software and avoid manual report compilation activities
  • Establish dynamic update links and save time in regenerating the desired report.
• Interoperability
  • Import tnxTower or Risa Tower models
  • Interoperability with STAAD.Pro and other Bentley products for design, detailing, and drawing generations

SYSTEM REQUIREMENTS

Processor: Intel ® Core i7 or similar

Operating System: Windows 10 x64

RAM: 16 GB minimum, 32 GB recommended

Available Languages: English

Complementary Products: [[STAAD.Pro]]

Problem Description

A blank "Analyze Error" dialog is displayed when running the RAM Concrete Analysis. In some circumstances it can also result in "Analyze Error 4"

 or 

Note, Analysis Error 4 with additional details such as "Invalid Distance between nodes..." is another matter and happens when the program cannot mesh the model to the current geometry. For tips on resolving that see: RAM Meshing and Segmentation

Reason

The error is associated with corrupt settings in the Analysis Criteria dialog. See below. Common examples of bad settings include:

1. No solver selected.

2. Values of 0 for mesh parameters: Merge Node Tolerance, Max Distance Allowed Between Nodes, and Geometry Tolerance.

3. Large value for Minimum Number of Stations per Beam.

4. No Rigid End Zone option selected.

5. No Beam Torsion Stiffness option selected

We are working to prevent this from happening, meanwhile avoid closing the Ram Concrete Analysis module if the 'framing tables' process is running. 

Steps to Resolve

Redefine the settings with appropriate values. The program installed defaults can be found here:

RAM Concrete Defaults

Note, starting in version 17.02 future corruption of the analysis criteria should be prevented. 

See Also

RAM Meshing and Segmentation

Error or Warning Message

On computers running Windows 8, the following message appears when opening STAAD.Pro even when product licenses are available:

"Trial/Valid license was not found or trial period has expired! Switching to Restricted Mode..."

* The issue may affect other versions also. 

Explanation

Make sure that you have at least one license for STAAD.Pro and one license of design code are available to be used. You can check this from the License Checkout section in the License Management Tool (Go
to Start -> All Programs -> Bentley Engineering -> STAAD.Pro V8i ->
Select License Tools -> Select XM License Management Tool ).

If enough license is available, and you are still getting the message, then it could be a registry setup issue. STAAD.Pro uses registry entries to store licensing-specific settings. The settings are stored in a location accessible by all users, but only an administrator can modify them. Starting with Windows Vista, a copy of the settings is also maintained in a location that can be modified by a user. If the settings are never written to the location accessible by all users, the program may encounter a licensing error.

How to Avoid

Option 1: Run STAAD.Pro as an administrator one time.

1. Right-click on the desktop shortcut for STAAD.Pro, and select Run as Administrator. The program should open without licensing errors.
2. Activate any design codes/modules.
3. Close STAAD.Pro
4. Open it as a normal user. It should open without licensing errors now.

Option 2: Explicitly run the STAAD.Pro installer as an administrator.

1. Uninstall STAAD.Pro from the Programs and Features control panel if present.
2. After running the InstallShield extractor, navigate to C:\BentleyDownloads, and open a folder beginning with stpst followed by a version number. For example, the installer for STAAD.Pro 20.07.09.31 is located in a folder named stpst20070931en.
3. Right-click on the executable stored in this folder, and select Run as Administrator from the contextual menu.
4. The installer will reinstall the program and write the missing registry entries.

Note:

Steps in Option 1 can also be used for STAAD.foundation if the message "SELECT license type is not configured yet. Please run “SELECT license Assistance” to configure it" is reported while opening it.

Also the same steps in Option 1 can be used for SectionWizard if it is starting in Demo mode while opening it as a standalone program.

See Also

[[SELECTsupport TechNotes and FAQs]]

Other Language Sources

Español

I am getting a warning “WARNING- TD or TB IS ZERO IN USER TABLE …” What are these values ?

When a user table general section is defined, the software needs to know what thickness ( t ) to use to calculate the D/t or b/t ratios where D is the section depth and b is the flange width. This information is necessary for classifying the elements of the cross section like webs and flanges during the design phase. TD is the thickness associated with the depth or in other words an equivalent thickness of the web that can be used for classifying the web (used as t in D/t). TB is the thickness associated with the width or in other words an equivalent thickness of the flange that can be used for classifying the flange (used as t in b/t). Since user defined sections could be of any shape and form, it is not possible for the software to find out what value to use for these terms and so these are left as zero and a warning is generated to make the user aware of it. The user needs to input appropriate values for these items.

This page contains FAQs related to Modeling in STAAD.Pro.

Please use the tree structure on the left to browse to the individual FAQs ( wikis ).

1. Section Properties not Entered for Member
2. Analyzing Multiple Disjointed Structures
3. Applying Line Loads on Plates
4. Modeling a Retaining Wall
5. Beam and Plate Orientation
6. Compression Force in Tension Members
7. Connectivity Issues
8. Create Section by Specifying Profile Points
9. Defining Temperature Load
10. Fixed and Enforced Support
11. Difference Between Plate, Shell, and Surface Elements
12. Distributing Wheel Loads
13. Total Joint/Element Limits Exceeded
14. Steel Section Encased in Concrete or with Concrete Core
15. Center of Gravity
16. Model Solid Rods
17. Modify Section Database
18. New Section Database
19. Convert "SET Z UP" to "SET Y UP"
20. Define Cable Section
21. Total Weight of Plates
22. Modeling Corrugated Steel Plates
23. Scale Down Supports
24. Specify Values of Stiffness for Compression and Tension at a Support
25. Edit Load Rules for Auto Load Combination Generation
26. Joint Coordinates Modified when Model Moved
27. Load Path Consideration
28. Modeling & Designing Gusset Connection
29. Model Shear Walls Using Plates
30. Model Slab on Top of Beams
31. Multiple Support Conditions in Same Model
32. Cannot Copy a Member, Node or do Transitional Repeat
33. Specify Seismic Weights Through Reference Load Cases
34. Aspects to Consider Analyzing Mat Foundations
35. Create Material Macro
36. How to convert a LOAD COMBINATION to a REPEAT LOAD
37. [[ERROR***MATERIAL GROUP AND EXPLICIT CONSTANT SPECIFICATION CANNOT BE USED TOGETHER]]
    
38. [[Modeling base plate with anchors in STAAD.Pro]]
39. [[How to measure node to node distance and dimension beams in STAAD.Pro Connect Edition ?]]

40. [[Customizing the Interface in STAAD.Pro Connect Edition]]

41. [[Identifying face numbers for Solid Elements]]
42. [[Different member release for different load cases]]

43. [[How to use loads of the same loading type in mutually exclusive combinations when using automatic load combination]]

44. [[Loads are not displayed in the STAAD.Pro graphical user interface]]

45. [[“WARNING- TD or TB IS ZERO IN USER TABLE …”]]

RAM Structural System CONNECT Edition Version 17.02.01 SES Release Notes

Anticipated Release Date: February 2021

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.

This is a minor release, correcting some issues that affected some users of v17.02. The Release Notes for that version contain important information not included here in these abbreviate Release Notes. They can be found at:

https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/52610/ram-ss-v17-02-release-notes

Installation Instructions:

If you have enabled the CONNECTION Client you will automatically be notified of the newest version and will be able to update through that service by simply selecting the update command. Otherwise, this version can be found on the Bentley Software Fulfilment web page by logging into CONNECT Center and selecting the Software Downloads icon. Search for “RAM Structural System” and select the latest version.

Security Risk Advisory:

Not applicable to this release. Every effort is made to ensure that there are no security risks in the software. There are no known security issues, no issues were addressed in this version.

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.

Yield-Link

The capability of analyzing and designing moment frames utilizing the Simpson Strong-Tie Yield-Link connection was implemented in v17.02. Some enhancements and corrections have been made to that implementation.

• When the beam or column flange width is inadequate for the width of the Yield_Link size, the previous version gave a warning message, but the message didn’t indicate whether the problem was the beam width or the column width (or both). The message has been enhanced to indicate whether the problem is with the beam width or column width, and it lists the width required to accommodate the assigned Yield-Link size.
• In the joint graphic in the Joint View/Update dialog in Steel – Standard Provisions mode, “Side A” and “Side B” labels were added to clarify which side of the column was which.
• An error in the calculation of the demand capacity ratio for the Buckling Restraint Plate Bolt, Vuy-bolt / RnVy, was corrected; the calculated ratio was double the actual demand capacity ratio. Joints that would have otherwise passed this check may have been reported as having failed.
• An error was corrected in the Joint View/Update dialog in Steel – Standard Provisions mode. The program did not recognize any selections made by the user for the Side B Yield-Link size (the program correctly recognized selections made by the user for the Side A Yield-Link size).

Diaphragm Forces Report

Three options are now available for the Diaphragm Forces Report: Resultants, At Discreet Points, and Resultants and At Discreet Points. The values at Discreet Points was added to the report in v17.02, but because of the length of report that resulted, it was decided that the user should be given the option of obtaining the short report with the Resultants or the longer report with the values at Discreet Points, or both.

Table Editor

The Table Editor (Tools – RAM Table Editor) in RAM Manager has been enhanced to allow Copy and Paste; values can be pasted into the fields, eliminating the need to edit the values one by one. To do this, select the Value heading to highlight the entire column of data, and then Copy that column using Ctrl-C, or paste in values using Ctrl-V. It has also been enhanced to include the capability of editing the Detailing values that were added to the ramaisc.tab Master table in v17.02.

Error Corrections:

Some program errors have been corrected for this version. 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 know these errors are disruptive, we apologize for any inconvenience this may cause.

Steel Column

B1 AND B2 REFERENCES:  The references for the B1 and B2 equations shown in the report were incorrect for the AISC 360-10 and AISC 360-16 specifications.

Effect: Report error only. When designing per AISC 360-10 and AISC 360-16, the B1 and B2 equation references for columns encountering B1 or B2 errors were listing older specification references.

Concrete Column

ACI 318-14 LIMIT ON NET TENSILE STRAIN: V17.02 was enhanced to include the tension strain limit of 0.004 for members with low axial load according to ACI 318-11 Section 10.3.5. However, this requirement is not required in Chapter 10 (Columns) in ACI 318-14, and should not have been applied to columns when the Code selection was ACI 318-14.

Effect: The limit of 0.004 on the net tensile strain of the reinforcement for lightly loaded columns was enforced on columns under ACI 318-14 even though it is not required for that code.

ACI 318 MAGNIFICATION FACTOR EXCEEDS 1.4: Some columns in some models in v17.02 reported that the Magnification factor, delta, exceeds 1.4. Work on an enhancement to check and give this warning is currently being done for a future version, but was not intended to be in v17.02. However, the partially complete work caused this warning to incorrectly appear.

Effect: Erroneous message. This has been removed until the feature is complete in a future version.

ACI 318 EFFECTIVE LENGTH FACTOR FOR Pc CALCULATION: Starting with v17.01, the value of  k used in the calculation of Pc for sway members was limited to 1.0, but for nonsway members the calculated k from the nomograph was applied.

Effect: Effective length factor used in the calculation of Pc may have been different than 1.0. For consistency the value of k is now always set to 1.0 in the calculation of Pc.

Frame – Analysis

WIND AND SEISMIC LOAD CASES CORRUPTED: Wind and seismic loads cases may have become corrupted when storie or diaphragms were subsequently deleted and added in the Modeler.

Effect: Program crash. It may have been necessary to recreate the wind and seismic load cases.

SLOPING COLUMN REACTION MOMENTS*: The reaction moments at foundation nodes were calculated and reported incorrectly for sloping columns. The Frame Reactions report and the Process – Results – Reactions command listed incorrect moments.

Effect: The reported and displayed reactions results for moments at the base were not correct at sloping column.

USER-DEFINED WIND LOAD ON SEMIRIGID DIAPHRAGM: If a user-defined wind load on a semirigid diaphragm included eccentricity, the program may have incorrectly calculated the wind forces projected onto semirigid diaphragm edges. This resulted in excess loads.

Effect: Excess wind loads may have been applied to semirigid diaphragms.

RIGID END ZONE INFORMATION IN BEAM MEMBER FORCE REPORT: When the option to Include Effects for Rigid End Zones was selected with a Reduction % specified, the Member Forces report listed the Reduction % incorrectly. It listed the value of (100% - Reduction %), rather than Reduction %.

Effect: Report error only, an erroneous rigid end zone reduction value was reported.

EUROCODE EN 1998-1:2004 SEISMIC AND RESPONSE SPECTRA: The Loads and Applied Forces report crashed if the model included Eurocode EN 1998-1:2004+A1:2013 seismic or response spectra load cases.

Effect: Report crash. Analysis results were valid.

Frame – Steel Standard Provisions

NOTE: The Joint Code Check command has been disabled for this version if the selected Code is AISC 360-05 ASD, AISC 360-10 ASD, or AISC 360-16 ASD. The program was using ASD load combination forces, but was using LRFD design checks, which was unconservative. The Joint Code Check reports showed that the checks were LRFD checks, so the error should have been obvious if the reports were carefully reviewed. If joint checks were performed in any version previously using AISC 360-05 ASD, AISC 360-10 ASD, or AISC 360-16 ASD, it may be advisable to recheck those joints using LRFD. The Joint Code Check command for ASD will be reactivated in a future release after the defect has been corrected. Note that the error only affected ASD, it did not affect LRFD design.

Frame – Steel Seismic Provisions

YIELD-LINK INVALID FRAME TYPE WARNING: If an unusual sequence of steps was taken, the Seismic provisions member code check may have terminated with the message, "Yield-Link Conn. Invalid Frame Type", even if the Yield-Link criteria was correctly set to Yield-Link SMF (R=8) and the frames were assigned to be Special Moment Resisting Frame.

Effect: Seismic code checks were not performed.

ISM

SHOW IN STRUCTURAL SYNCHRONIZER: In the File – ISM – ISM Options command the selection of the option Show in Structural Synchronizer wasn’t respected, the Structural Synchronizer always launched.

Effect: Nuisance. User couldn’t prevent the Structural Synchronizer from running when creating ISM repositories.

SHARED LAYOUT TYPES: The capability of creating ISM repositories from models that use shared floor types (i.e., the same layout type at multiple stories) was implemented in v17.02, and works correctly without requiring that the layout type be copied into distinct layout types for each story. However, an old message still appeared indicating that the shared layout type had been duplicated into distinct layout types.

Effect: Erroneous message only. The layout type was not duplicated into separate layout types.

Problem Description

Results using version 6.21.01.09 differ from prior versions.

Explanation

This release installed a faulty version of the Mstload6.exe file used in calculating loads. The corrected file is installed with release 6.20.01.10 or 6.20.01.11.

Avoidance

Update to the latest build.

Note, another build 6.20.01.12 was briefly available where a similar problem with Mstload6.exe occurred. That version was removed from our download site, but if you have a copy of that build installed you should remove it and restore build 6.20.01.11.

See Also

[[MStower Wind Loads on Lattice Towers]]

Webinar

A Webinar: Design Resilient Steel Structures with Yield-Link® Moment Connections in RAM Structural System was presented February 4, 2021, and is available on-demand. This wiki includes links to the webinar and to other useful resources on the topic. Several questions were submitted during the webinar, the Q & A is included below.

Presented by:

Tim Ellis, PMP, Market Segment Manager, Simpson Strong-Tie

Brandon Chi, P.E., S.E., Lateral Systems Engineering Manager, Simpson Strong-Tie

Allen Adams, P.E., S.E., Chief Structural Engineer, Bentley Systems, Inc.

Presented Live: February 4, 2021

Link to Webinar Recording, On-demand:

https://gateway.on24.com/wcc/eh/2541253/lp/2953602/bentley-webinar-design-resilient-steel-structures-with-yield-link-moment-connections-in-ram-structural-system

Link to Presentation PDF: link

Technical Documentation

Time limitations on the webinar only allowed for an introductory presentation on the Yield-Link connection and its analysis and design in the RAM Structural System. Several resources are available for more comprehensive information on the Yield-Link moment frame connection and to assist in modeling, analyzing and designing the connection in the RAM Structural System.

For more information on the Yield-Link connection, see the Simpson Strong-Tie Yield-Link Moment Connection Design Guide:

https://embed.widencdn.net/pdf/plus/ssttoolbox/3pgf3rhpma/F-L-YLMCDG20.pdf?u=cjmyin

For a detailed step-by-step guide to Yield-Link in the RAM Structural System, see this wiki, “Specifying and Designing Yield-Link in the RAM Structural System” on Bentley Communities:

https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/53043/specifying-and-designing-yield-link-in-the-ram-structural-system

Yield-Link is a prequalified connection. See Chapter 12 Simpson Strong-Tie Strong Frame Moment Connection of AISC 358-16 Prequalified Connections for Special and Intermediate Moment Frames for Seismic Applications.

Yield-Link: https://www.strongtie.com/solutions/steel-construction/yield-link#:~:text=Our%20Yield-Link%20connection%20is%20precision-made%20to%20meet%20the,that%20keeps%20structural%20steel%20buildings%20strong%20and%20safe.

RAM Structural System: https://www.bentley.com/en/products/product-line/structural-analysis-software/ram-structural-system

Q&A

Does a stiffness reduction need to be considered for the drift check?

For moment frames using RBS’s, it is recognized that the reduction in frame stiffness due to the reduced cross-sections in the beams results in greater drifts. This can be accounted for either by amplifying the calculated drifts or by modifying the stiffness of the beams at the location of the reduced beam sections; RAM Structural System has the option of doing either. For moment frames using Yield-Link, in the RAM Structural System the beam/column joint panel is automatically represented in the analysis by a spring that explicitly accounts for the reduced stiffness of the Yield-Link connection. The reported drifts therefore include the impact of those reduced stiffnesses, and do not need to be further amplified.

The prequalified method given in AISC 358 does not calculate and consider the bending of the column flange in frame drift.  Depending on beam depth, could there be a significant difference between calculated and actual drift?

For the overall requirement of 4% story drift in AISC 341, deflection from the contribution of the beam, column and connection are all included. However, as part of the test reporting, portions of the total inelastic rotation (total rotation minus elastic rotation) contributed by each component of the test specimen are reported. In the earlier versions of AISC 341, this inelastic rotation requirement was 0.03 radians. From our testing, we met this 0.03 radian inelastic rotation requirement. In addition, we just finished a validation testing in Virginia Tech using a “T-Configuration” setup with a beam length of 16’-0” and column height of approximately 12’-0”. Performance between the portal frame test setup and “T-configuration” setup is very similar. In Chapter 12 of AISC 358s2-20, using the equations in Step 11, one can calculate a rotational spring to represent the Simpson Strong-Tie Yield-Link Connection. (See the Simpson Strong-Tie Yield-Link moment connection modeling guide for comparison of test result and calculated deflection using a rotational spring to model the Yield-Link connection: F-L-SMFYLCMG). From an analysis perspective, this effect is included in the panel spring stiffness used by RAM Structural System.

RBS’s yield slighter higher drifts as compared to WUF-W, for the same member sizes. What would be the comparison for the Yield-Link moment connection?

For the Yield-Link Connection, in addition to the beam and column, the Yield-Link connection also contributes to the overall drift. Depending on beam, column and Yield-Link connection sizes, the drifts using Yield-Link Connectioncan vary from approximately 5% - 10% greater than those for RBS, and up to 10%-20% greater than a WUF-W.

What Rigid End Zone setting should be specified for this connection for strength and drift analysis?

The option to Ignore Effects should be selected. The panel spring stiffness used by the program accounts for the reduced stiffness of the panel zone.

How are the gravity shears and moments at the ends of the beam accounted for in the Yield-Link connection?

The beam shear due to seismic, wind, and gravity loads are transferred to the column through the shear tab. Required shear strength Vu, of the beam and column shear tab connection is noted in AISC 358s2-20 EQ 12.9-34 (see excerpt below). Not only is the shear tab/beam web required to resist all the gravity loads, but it is also required to resist the shear loads from the Yield-Link Connection when the Yield-Link connection at both ends of the beam have reached its maximum probably moment capacity (M_pr). This is similar to the RBS beam web shear design requirement at the beam web-to-column connection.

The Yield-Link connector is only designed for axial forces, so the beam end moments are resolved into seismic, wind, and gravity axial loads on the top and bottom connectors (the gravity moments generally induce an axial tensile force in the top connector and an axial compressive force in the bottom connector). These are automatically calculated and considered in the design in the RAM Structural System.

Does the vertical line of bolt in the shear tab have horizontal slots to allow for rotation?

Except for the bolt at the mid-depth of the beam, the holes are slotted to allow the beam to rotate around the center bolt (as the Yield-Link connectors shorten and elongate) without inducing any moment on the shear tab.

If the shear tab bolts have horizontal slots to allow rotation, how are axial/collector loads transferred into the columns? Is that captured in the analysis using RAM Structural System?

The vertical line of bolts (with horizontal slots in the shear tab) are designed to resists the vertical shear loads (Vu). The horizontal line bolts (those aligned with the centerline of the beam) with vertical slots in the shear tab are designed to resist the axial loads. To increase the axial load capacity, more horizontal bolts can be provided. Both vertical and horizontal slotted holes in the shear tab are designed to accommodate a connection rotation of +/- 0.07 radians (see AISC 358s2-20 Step 15.2). Both vertical and horizontal forces in the shear tab and beam web are captured in the analysis and design in the RAM Structural System.

Are the bolts slip critical?

The Link stem-to-beam flange bolts are pre-tensioned bolts only, not slip critical. The contact surface between the Yield-Link and the beam flange are required not to be painted (to match testing conditions). However, no surface preparation is required. All other bolts in the Yield-Link connection can be installed snug-tight.

What does the composite deck attachment detail look like at the connection? How does the deck bear on the top flange if the Yield-Link connector is in the way?

For composite deck applications, Simpson Strong-Tie offers a cover plate that goes over the Yield-Link connection (see https://www.strongtie.com/structuralsteel/ylc_cover/p/yield-link-cover-plate).

What is the “protected zone”?

A protected zone is the region where inelastic deformation/movement is expected to occur. For the RBS connection, the protected zone includes the reduced beam section region and the distance from the radius cut to the face of the column in the beam. For the Yield-Link connection the protected zone is shown in the figure below:

Is this available for Special Moment Frames (R = 8)?

The Yield-Link connection can be analyzed and designed in the RAM Structural System for SMF (R=8), IMF (R=4.5), and MF (R=3).

What are the beam bracing requirements for Yield-Link compared to RBS and WUF-W?

Because the connection is designed such that the Yield-Link connector is the fuse element while the beams and columns remain elastic, the stability beam bracing requirements of Section D1.2 of AISC 341-16 are not required for the Yield-Link moment frames. The bracing merely needs to conform to the bracing requirements of AISC 360.

How good is the building’s re-centering ability with the Yield-Link moment frames?

From our FEMA P695 study, because of the better hinge distribution along the height of the structure, less residual drift was observed. However, the Yield-Link connection does not have any re-centering abilities, same as any other standard moment connection.

How do you replace the top Yield-Link connector if there is a concrete deck above the beam?

Limited concrete removal above the Simpson Strong-Tie concrete cover is expected in order to replace the Yield-Link at the top of the beam flange. There is no metal deck directly on top of the Yield-Link connection, only on the light gage Yield-Link cover. In addition, the Yield-Link cover is only attached at the end of the Yield-Link connectorat the beam flange. After removal of the concrete above the Yield-Link cover, the cover can be pried open to expose the Yield-Link at the top of the beam.

Why are Yield-Link connections designed with combinations with the overstrength factor, W₀, as it is not a code requirement for RBS?

In Yield-Link moment frames, the Yield-Link connector is the yielding element. In order to assure that all of the yielding takes place in the connector and that the rest of the system remain elastic, the beams, columns and connections are designed for omega-level forces. For RBS’s, the connections must be designed for the shear given by Eq. (5.8-9) of AISC 358-16, which is based on the probable maximum moment, Mpr, at the center of the reduced beam section, to ensure that the connection doesn’t fail before the reduced beam section.

It was indicated that we need to over-design the columns and beams for the Yield-Link moment frames. How much higher do we need to design?

The members need to be designed for combinations that include seismic forces that have been amplified by the overstrength factor, W₀. This is described in Section 12.4.3 Seismic Load Effects Including Overstrength in ASCE 7-16. W₀ factors are given in Table 12.2-1 and, for steel moment frames, has a value of 3.0.

Does RAM Structural System perform the Column Seismic checks for the W₀ load combinations?

As required for Yield-Link moment frames, RAM Structural System does perform the member and connection checks using the load combinations with the overstrength factor, W₀.

Can the RAM Structural System run the analysis and select the minimum acceptable links automatically?

No, not currently. The engineer must assign initial Yield-Link sizes. The default sizes are a good starting point. Using the View/Update feature, the engineer can quickly and easily

Have there been any parametric studies on how Yield-Link would perform against other proprietary moment frame connection systems?

Each system has its own strengths and weaknesses, and some of those will be more or less important on any particular project. As is the case for all framing systems, least-weight is not necessarily the best. Performance, drift, retrofit, repair, initial cost, lifetime cost, etc., are all considerations. Owners don’t all view these the same. As is the case for all framing systems, least-weight is not necessarily the best. RAM Structural System has extensively implemented the analysis and design requirements of several moment frame connection systems. Engineers are invited to perform those comparisons in RAM Structural System on their specific project to help determine the most economical system for that project.

Is there a Simpson catalogue that details each of the Yield-Link sizes?

See page 11 of the Simpson Strong-Tie Yield-Link Moment Connection Design Guide, listed at the beginning of this document: https://www.strongtie.com/structuralsteel/smf-yl_link/p/yield-link-moment-connection

Are CAD files generated so we can draw up the connection for interferences?

Detailed CAD files (DXF) are created using the Export Yield-Link DXF command. These include frame elevations and joint connection details. A comprehensive set of typical details and notes is also created. These files are suitable for any drafting or detailing program.

How is the AISC 360 Direct Analysis Method’s stiffness reduction considered, for strength vs drift check?

This question is applicable to all frames, not only to the Yield-Link moment frame connection. The AISC 360 Direct Analysis Method requires that a 0.8 stiffness reduction be applied to all stiffnesses that contribute to the stability of the structure, and that an additional reduction factor, tau_b, be applied to the flexural stiffnesses. This is required for the analysis used to perform the member strength checks, but not the drift checks. Due to the short time allotted for the demonstration of the RAM Structural System in the webinar, and to avoid a lengthy discussion on a tangential topic, this issue was not addressed. However, for a real project the following procedure should be performed in the RAM Structural System. When checking drift and to get the building periods and seismic story forces, unselect the Criteria option to include the Direct Analysis Method stiffness reduction; select the gravity, wind, and drift seismic load cases to be analyzed; analyze; and then check the drifts compared to the appropriate wind and seismic drift limits. Also check for Torsional Irregularity. Modify sizes as necessary. When drifts are acceptable, proceed with the strength checks. Select the Criteria option to include the stiffeness reduction; select gravity, wind, and strength seismic load cases; analyze; and perform the standard and seismic code checks.

In the RAM Structural System, are the selected drift control points the only ones used in the calculation of drift ratios and torsional irregularity determination, or does the program consider every point on the diaphragm?  If the Torsional Irregularity check reveals an irregularity, then to what part of the design process would you have to cycle back to to fix the loading to comply?

This question applies to all frames, not only to the Yield-Link moment frame connection. In order to keep the Drift report from being unduly long, the program only investigates drift at the control points specified by the engineer. Since only the center and the extreme corner points are of interest (the rest won’t control), the user typically only needs to specify a very few points, which can be done very quickly. In the example used in the demonstration it was only necessary to specify and consider three points.

If the structure is Torsionally Irregular, ASCE 7 requires that frames be designed for the seismic load cases that include the accidental torsion, that is, the plus and minus 5% eccentricity cases (four cases total, two in each axis), and requires that frames be designed for the wind load cases that include torsion (12 cases total). If the structure is not Torsionally Irregular, ASCE 7 allows the frames be designed for the seismic load cases that don’t include the accidental torsion (two cases total, one in each axis, through the center of mass – see Section 12.8.4.2), and allows the frames to be designed for only the wind load cases that don’t include torsion (four cases total – see Appendix D). RAM Structural System has options to automate each of these.

Has Yield-Link been used for any projects under the jurisdiction of California DSA? Were there any issues getting approval?

Yield-Link connection has been used in at least 5 completed DSA projects that have gone thru DSA review from various DSA offices and locations. The latest currently under construction is the Fremont Unified High School District Office building in California. The entire lateral system for the structure utilized Yield-Link Moment Connections.

Originally the connection approval would have to go through the alternate means process for beam sizes larger than what was listed in AISC 341-16. However, with the release of AISC 358s2-20, W36 columns/beams and 6 in² Yield-Links are now permitted to be used in DSA projects without the additional requirements of the alternate means process.

Is the Yield-Link feature available in STAAD.Pro?

No, it is not currently implemented in STAAD.

Is there a yield link option in RAM Elements?

No, it is not currently implemented in RAM Elements.

I have defined a series of shear walls using plates and would like to use Results Along Line feature to obtain the shear wall forces for one particular wall at a time. How can I do that ?

When you want to draw the cut line for a particular wall, ensure that you only have that wall in your view ( select the wall elements and go to View > View Selected Objects Only ). Change your view to a  suitable elevation view so that you see the wall from the front. Now when defining the cut line, choose the option "Cut By Line" and draw the line from one edge of the wall to the other to define the local x for the line. Click above or below the line to define the local Y for the line. Your cut line will now cut only that particular wall and not any others lying in its vicinity. For better results, try to draw the line through the center of any row of plates and do NOT draw the line through the nodes of a plate mesh.

Although the procedure above mentions about walls but the same is applicable for cutting sections through slabs as well.

ALTHOUGH THIS WAS POSSIBLE IN OLDER VERSIONS OF v8i BUT IT IS NOT AVAILABLE ANYMORE IN MORE RECENT VERSIONS. THE RESULTS ALONG CUTLINE FEATURE HAS BEEN REVAMPED IN THE STAAD.PRO CONNECT EDITION AND ANYONE USING THE RESULTS ALONG LINE FEATURE SHOULD USE STAAD.PRO CONNECT EDITIION VERSION 22.02.xx.xx OR HIGHER.

Problem Description

When I am running LIMCON, the program opens for few seconds and then crashes.

Solution

Please uninstall the existing Connection Client from your machine. Go to Control Panel\Programs\Programs and Features\Uninstall a program; right-click on it and select 'Uninstall'. Then download and install the latest one. 

It is available for download from the ‘Software Downloads’ tile at connect.bentley.com. Search for 'CONNECTION Client'. 

You will download the one (32-bit or 64-bit) fitting your machine's configuration. In case you are not sure, you can check under Control Panel\System and Security\System or your IT personnel can help you out. Please note that most of the new machines are configured as 64 bit OS.

Once downloaded, right-click on the file and select the option "Run as administrator" (though you may be the administrator for your machine). This ensures that the registry keys are set properly in the machine.

In some cases, a machine reboot is required after installing the CONNECTION Client program to bypass the crash.

See also

Structural Products and the CONNECTION client

Bentley CONNECT Overview

List

Problem Description

Note: This issue has will be resolved in the update version, v17.02.01.**. Installing this version should solve the problem.

When running the Ram Frame analysis for Wind Loads, especially on semi-rigid diaphragms after some change to the Modeler - Story data, the program may crash. 

Solution 

In most cases if the Wind load case is edited (RAM Frame Loads - Load cases) then it works. You don't have to actually change anything, just click OK to reset the Wind Load case variables.

Problem Description

After installing RAM Structural System and configuring the license correctly, the program fails to open. Attempting to open either the desktop or Start menu shortcut for RAM Structural System does not respond.

Steps to Resolve

1. Right click on the License Management Tool from the start menu (Start -> Programs -> Bentley Engineering -> RAM Structural System v14.07 -> License Management Tool) and select the option "Run as administrator".
2. The License Management Tool opens, at the bottom of the window in the lower left corner, you will see the Storage:Settings stored for: Current User Only

3. Click on Elevate to All Users; you will get few messages informing you that the setting is being changed. Click on ok, configure the license and activate the products. RAM Structural System will open fine now.

See Also

[[RAM Manager fails to open on 64-bit OS]]

[[License Management Tool closes abruptly]]

Configuring structural products for selectserver

Ram Modeler license is disabled.

What Load Combinations are passed from RAM Structural System to Ram Connection?

When Ram Connection for RAM SS is launched the program pulls the load combinations from Ram Frame Steel - Standard Provisions. Combinations from the Ram Frame - Steel - Seismic Provisions mode are also imported when that mode is current (green light for model status).

The user can override this with the Load Combinations ribbon menu dialog box launcher as indicated below.

If this option is unchecked, then Load Combinations need to be added within Ram Connection using Add/edit or Generate in the same ribbon menu.

Why do I get an error, "None load combinations could be read from the model."

Since the program is trying to pull the combinations from RAM Frame, this error will occur for all gravity models that do not have any Ram Frame combinations defined. To proceed in such a model, uncheck the option to "Include RAM Frame - Steel Provisions Mode load combinations as noted above, then manually define or generate new load combinations. 

Why is the design being checked for single load cases?

Refer to https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/8105/ram-connection-capabilities-and-modeling-faq#load_case 

Why do I get an error with imported load case IDs?

Depending on the version of Ram Connection, you might encounter one of these error messages:

1. "Invalid load condition identifier "**". it must be 1 to 5 characters long and the first character must be a letter."
2. "Error in formula "dl+0.6W*", Load case "W*" does not exist

The first issue pertains to the length of the Load Case IDs, In early versions of Ram Connection this was limited to 5 or fewer characters, so the Load Case names in RAM Frame needed to be short. 

The second pertains to load case names with unexpected symbols in the name. For example, if the underscore character (_) is sed in a load case name in Ram Frame this can cause Ram Connection to misread or truncate the load case names. 

Both of these specific issues have been addressed in the current version or Ram Connection (13.04.00.183 as of this entry), but if you encounter such a problem, try simplifying the load cases names in Ram Frame - Analysis mode. 

See Also

RAM Connection Capabilities and Modeling FAQ

RAM Elements Load Combos [FAQ]

[[Ram Connection Seismic Provisions Settings]]

[[Connections for Gravity Members are Designed for Zero Force]]

Troubleshooting Errors when Assigning Connections

Some Bentley products require a component called the Bentley IEG License Service to function. The component handles the licensing functions on behalf of programs that rely upon it. This article explains how the licensing works and how it differs from "trust licensing" which is used by other Bentley products.

Products that require it

The following products and versions require the Bentley IEG License Service:

How it works

SELECTserver provides the ability to check out or assign licenses for a specified duration. The licenses remain checked out to a user and computer and cannot be checked out elsewhere until the license is checked in again.

The Bentley IEG License Service utilizes this functionality. It automatically checks out licenses for a product as needed, usually when the product is first started. Licenses are checked out for a duration of two days. This duration ensures that a license is not prematurely returned if a product is running continuously overnight.

Once a license is checked out, the Bentley IEG License Service monitors the program that requested it. When the program closes, the license is automatically checked in again.

How it differs from "trust licensing"

The Bentley IEG License Service follows the concept of "concurrent licenses." If a company has x number of licenses for a product, the Bentley IEG License Service will permit x users to utilize the product simultaneously. An additional user will be denied access until a license becomes available.

This concept differs from the concept of "trust licensing" which merely reports usage data instead of actively restricting users. For the sake of flexibility and fault tolerance, trust licensing products technically allow usage in excess of the total number of licenses purchased, but such use should be discussed with a Bentley sales representative for cost and conditions. Please refer to Understanding, Monitoring, and Managing Usage for more information about trust licensing and usage.

Note : More recent versions ( than what is mentioned in the table ) for most of these products do not use the Bentley IEG License any more and does not check out licenses. These products now use Trust Licensing.

Reinstalling an old application that requires the IEG License Service

If you are reinstalling an old application that requires the IEG License service, but no longer have that installer, first double check in your Bentley Downloads folder, look for iegls*.*. If it's not there file a service request and ask for IEGLicense Service verison 2.00.20.01 English 32 bit (iegls02002001en.msi).

See Also

Viewing and Checking In Licenses Using the Site Administration Page [TN]

Release Date: 26th February 2021

Version: ISM Revit Plugin CONNECT Edition V11 Update 2 (Patch 1)

Version Number: 11.02.01.05

Download Instructions

ISM Revit Plugin can be downloaded from Bentley Cloud Services here. After signing in to CONNECTION Center, select Software Downloads under My Services. Once on the Software Fulfillment page, ISM Revit Plugin installers can be located by performing a search on "ISM Revit".

Special Notices

The installation of ISM Revit Plugin CONNECT Edition will automatically uninstall any previous versions that were installed. This version of ISM Revit Plugin can be run in Revit 2019, 2020, and 2021.

ISM Revit Plugin requires ISM and Structural Synchronizer (both of which are installed with Structural Synchronizer). More information on ISM and Structural Synchronizer can be found here.
 

Bug Fixes

Fixed an issue which prevented some users from launching the application.

RAM Connection CONNECT Edition v11.1 Release Notes

RAM Connection CONNECT Edition v11.01.01.240 Release Notes – Updated August 2017

Enhancements:

1. New ribbon style with cleaner look.
2. New Backstage view to manage models, file operations, interoperate with other software, adjust personal information and setting options.
3. RAM Connection now includes Bentley CONNECT Advisor v10.1.0 which is a CONNECT service enabling Bentley users to have real time access to LEARN content, recommendations for more productive workflows and the ability to embed an Expert Engineer to their CONNECTED project.

Resolved Issues:

1. In the anchor design for base plates, the load eccentricity (e'N) was sometimes being calculated as a negative value. Although the calculation was correct, the design code specifies that this value should always be considered as positive. This is now corrected.
2. Base plates were not being optimized for ASD design method, because Appendix D of ACI 318 only works with LRFD. This is fixed and the base plate is optimized regardless of the anchor design, since the base plate optimization can be ASD or LRFD.
3. For BS 5950 or EN 1993, the Structural Integrity check was a global (model based) parameter. Now it is a local (joint bases) parameter since in a model, there can be connections that require it and connections that do not.