The load combinations considered for regular/irregular building in sizing are with factor 1 for all load cases. Can this factor be an input?

Factor can’t be an input, as for sizing of footing/Pile-cap different factors are to be considered for dead, live and other load cases. However, user can create his own load combination templates by using ‘Add Load Combination’ option and creating a new template. User also can add or remove load combinations as per requirements. For more information refer Topic “Load and Load combinations” from help Content.

While trying to design RCC beam using ACI 318, exporting the data from ETABS in FPS (foot-pound-second) system, but the data that is being reflected in RCDC is in MKS (meter-kilogram-second) system.

RCDC refers to ACI-318M-2011 (metric units) code. If data is exported in feet and inches RCDC internally changes the forces in to kN and m. Working environment in RCDC is in MKS units. User can provide the input data in kN and M unit for RCDC. The output can be generated in inches unit. Refer ‘Style Manager’ in RCDC for the same.

 Is the Vertical axis of STAAD and RCDC Same? At the time of importing the loads in RCDC if we give X direction to Earthquake X and Z direction to earthquake Z, then it will convert it in its relevant direction?

          RCDC is a design software and imports the analysis forces from STAAD for design. There is no specific axis of the RCDC.

          example: for column design, RCDC get the forces along major and minor axis. whatever the load cases defined in analysis, RCDC get the forces for local member and it designs the member. 

          Defining direction for Eq forces i.e. X and Z, it just a load case type. it will just help to create load combinations as per load type. if Eq-z is available in Analysis and it is defined as Eq-Y then it doesn't affect the            design forces of the member. Forces for that load case will remains same. EQ-Y is just a nomenclature for that load case

Specifying Load Combinations and Analysis Commands in STAAD.Pro On-Demand Training
Learn how to specify load combinations and analysis commands in the STAAD.Pro Analytical Modeler or the STAAD.Pro Physical Modeler using STAAD.Pro CONNECT Edition.

Reviewing Analysis Results in STAAD.Pro On-Demand Training
Learn how to review analysis results in STAAD.Pro CONNECT Edition.

Performing an Analysis with STAAD.Pro Advanced On-Demand Training
Learn how to perform an advanced analysis in STAAD.Pro CONNECT Edition using STAAD.Pro Advanced.

 Can I define concrete grade as 27 N/sqmm in RCDC for IS code design? How and what is the impact of this in design?

Yes, RCDC allows to define any grade of concrete in design. The maximum concrete grade is 100N/sqmm. User can add any grade of concrete in list and use for the member design in RCDC.

For section design, RCDC use the concrete grade which is defined by user. For checks like Tcmax in shear design, as the interpolation is not desire, RCDC uses the lower value defined in code as permissible shear stress in the design.

I created some connection templates using the RAM Connection mode inside STAAD.Pro. How can I get these templates transferred from my machine to a second user's machine?

To begin with I would direct you to the wiki article which you may be already familiar with as my suggestions would be based on that

communities.bentley.com/.../how-to-customize-a-ram-connection-template-in-staad-pro

Specifically refer to the section titled Your Custom Template File

First you need to copy the <group.name>.con file from within the folder in your machine as indicated in that section 

Please note that the file may be at the following location as well depending on which version of STAAD.Pro you are using
 
C:\Users\<user.name>\AppData\Roaming\Bentley\Engineering\STAAD.Pro V8i SS5\RAM Connection\Database\Connections\User

Copy the file and paste it at the same location within the second user's computer where you would like to copy the connection templates.

Now copy the same .con file in the following folder of the second user's machine

C:\…\SProV8i\STAAD\RamConnection\Database\Connections\United States\

From your machine, copy the connections.ini file from within your C:\…\SProV8i\STAAD\RamConnection\ConnectionTemplates\ and replace the same file in the second user's machine with that.

It is always better to keep a backup of all the files you are replacing in the second user's mchine, before you actually replace these.

This should get your templates transported to the second user's machine.

I am getting the following error during analysis. How do I fix that ?

***Error*** Modulus of Elasticity Missing For Element ...

The error means that material has not been assigned to certain elements. You can graphically find out those elements by choosing Select > By Missing Property > Missing Elasticity, as shown in the picture below

The elements with missing attributes will be highlighted. You may then assign the appropriate material to those elements using the graphical user interface.

Another quick way to fix the issue, specially of you have only one type of material for the whole model, is to go to the input command file and type in the following commands under the CONSTANTS section as shown next

For Steel:
CONSTANTS
MATERIAL STEEL ALL

For Concrete:
CONSTANTS
MATERIAL CONCRETE ALL

While analyzing a STAAD.Pro model I get a warning message

  ** WARNING ** A SOFT MATERIAL WITH (1.0 / 1.526E+01) TIMES THE STIFFNESS OF
                CONCRETE ENTERED. PLEASE CHECK.

What does it mean ?

During analysis STAAD.Pro checks whether the E value for the defined material varies widely from the E values for standard materials like Concrete or Steel and generates such warnings when it is so. The intention is to make the user aware of such discrepancies in case it is caused by error in input. Typically such warnings may be generated when the values used for the E are inconsistent with the units. For example E for concrete cannot be 3150 if input unit is pound inches. Similarly E for concrete cannot be 29000 if the input unit is in Kip-ft. So it is important to check for such inconsistencies when warnings like these are encountered.

Sometimes users intentionally define stiff or soft materials and assign these to members/elements to model certain structural entities/connections/boundary conditions in which case such warnings would also be generated but in such cases these may be ignored.

My hand calculations do not match the displacements being reported by STAAD.Pro. What may be causing this ?

When STAAD computes the displacement at a node using the stiffness method, the bending stiffness coefficients in the stiffness matrix include the contribution from

1) flexural deformation

2) shear distortion if it can be determined.

As a result, the joint displacements consist of the pure bending component plus the shear deformation component. Mostly when we do hand calculations we do not include the shear deformation component, and this may be responsible for the difference between STAAD's results and our expectation.

If shear deformation is eliminated from STAAD's calculations, this discrepancy will be removed. One can do that by specifying a command called SET SHEAR as shown next

STAAD SPACE

SET SHEAR

UNIT KIP FEET

JOINT COORDINATES

...

The bending coefficients will then include the contribution from flexural deformation only. It may be worth noting that the command does not affect plates and solids, and shear deformation will still be computed for those entities.

Issue: This error comes up while running STAAD.Pro :

 "Unable to load Bentley.LicLib.dll.Error:126.the specified module could not be found"

Resolution: Update to the latest version of STAAD.Pro by following the link below.

https://communities.bentley.com/communities/other_communities/sign-in_assistance_and_web_services/w/wiki/30658/software-download-instructions

If you cannot update to the latest version, please follow the steps below:

 Go to Add or Remove Program and completely uninstall the existing version of Bentley IEG License service.

 Search and download Bentley IEG License service from the above link and install it. Please note that you have to turn off all the selection as shown here. 

I defined a composite deck and I am getting the following warning during analysis

   ***WARNING: MEMBER     1 HAS COMPOSITE PROPERTY ASSIGNED TO IT AND HENCE THE MATERIAL CONSTANTS

               ARE SET AS THOSE OF STEEL. CURRENT SPECIFICATION IS IGNORED EXCEPT DAMPING RATIO.

What does the warning mean ?

Whenever one defines a composite section in STAAD.Pro, the software assumes the material for the beam to be steel and slab is assumed to be made up of concrete. The material properties for the steel beams are automatically read from the standard material properties for steel available in the software database. The warning is a generic one and is intended to inform the user that even if a different material property is assigned to these beams, STAAD.Pro will always use the properties of steel that is there in it’s database for these beams except for the damping ratio. The warnings are always generated, even if one assigns steel property to these beams, just to cover for the fact that one can actually change the properties for material Steel using the editor after defining it. So even if one does that, the software would still use the material properties in it's database for the composite beam. The warning is harmless and for information only more than anything else.      

What is SET NL and why is it required

OR

PRIMARY LOAD CASE CAN ONLY BE ADDED IF SET NL COMMAND IS USED

OR

" **ERROR- Number of Primary Cases exceeds value entered in SET NL Command …"

OR

*** ERROR: TOTAL NUMBER OF LOAD CASES EXCEEDED THE RELATIVE CAPACITY ASSIGNED FOR
PROCESSING PLATE RESULTS. USE "SET NL" TO INCREASE THE MEMORY CAPACITY.
IF ALREADY DEFINED THEN CONSIDER INCREASING "SET NL" TO AT LEAST # 693 !

SET NL command is required, in a file with multiple analysis commands, to let the software know how many primary load cases it would need to process so that the software can allocate the right amount of memory for the analysis and for storing the input/output data. A typical example of a file with multiple analysis commands is shown below

Load case 1
…
Load case 2
…
Load case 100
…
PERFORM ANALYSIS
CHANGE
Load case 200
…
Load case 201
…
Load case 300
…
PERFORM ANALYSIS
CHANGE

If such a file has 300 primary load cases ( REPEAT LOADs are counted as PRIMARY loads too ) you would add the SET NL command as show next

STAAD SPACE
START JOB INFORMATION
…
END JOB INFORMATION
SET NL 325
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
…

The number of primary load cases mentioned after the SET NL should be equal or little more than the actual, in case more load cases need to be added later. In the above example the number has been defined as 325 although the actual number of primary cases is 300. The value should not be too high ( say NL specified as1000 for only 300 primary load cases ) as in that case the software would reserve unnecessary amount of memory.
 
This command should be provided before any joint, member or load specifications.

Please note, if plates are present and you are getting an error similar to what is described in the fourth scenario mentioned above (the fourth question at the top of this post, indicated in bold), the SET NL value should be equal to the total number of primary loads AND load combinations in the model.

What is the meaning of the note reported in the Output file "*** NOTE: CAPACITY FOR MAXIMUM #    266 LOAD CASES IS ASSIGNED FOR PLATE LOAD"?

This note was added in the Output file to let the user know about the current memory capacity for processing Plate Loads or more specifically the maximum number of Load Cases that the Plate Load Processor can handle. If SET NL is not defined then additional Note is printed that will suggest the user to include SET NL command if the total load cases in the model are greater than the maximum assumed capacity.
Here is the Note:

"*** NOTE: CAPACITY FOR MAXIMUM {#max number of load cases that can be handled by Plate Loads will show up here} LOAD CASES IS ASSIGNED FOR PLATE LOAD."

If SET NL is not defined then the accompanying Note is:

"CONSIDER SETTING "SET NL" COMMAND TO THE TOTAL NUMBER OF LOAD CASES AND LOAD COMBINATIONS PRESENT, IF THE TOTAL NUMBER OF LOAD CASES AND LOAD COMBINATIONS ARE GREATER THAN THE AFOREMENTIONED CAPACITY".

While analysis or at the end of the execution if it is detected that the capacity [i.e. max number of load cases] for Plate Loads is less than the total number of load cases [Primary and Load Combinations] then Error will be issued by the engine giving the above information. Additionally, use of Set NL will be suggested on that occasion in the same error string:

" *** ERROR: TOTAL NUMBER OF LOAD CASES EXCEEDED THE RELATIVE CAPACITY ASSIGNED FOR PROCESSING PLATE RESULTS. USE "SET NL" TO INCREASE THE MEMORY CAPACITY. IF ALREADY DEFINED THEN CONSIDER INCREASING "SET NL" TO AT LEAST {#max number of load cases detected in the model will be shown here}"

Description

When I try to create and ISM in STAAD, I get the following errors. Unable to cast 'STAAD.Pro' COM object to 'OpenSTAAD' object. Check if 'OpenSTAADUI.tb' type library file is properly registered. Also no STAAD filename is provided. Unable to connect to 'STAAD.pro' instance. Check if STAAD.Pro application is running.

Solution A

To solve the issue, manually register the OpenSTAADUI.tlb file.  You can do this by following these steps:

1. Go to the Windows Start menu and select Run.

   2.  Type “cmd” in the Run dialog box then click OK.

 3.   You will see the command prompt dialog box appear.

 4.  Type the folder directory “CD C:\SProV8i SS5\STAAD”, click on “Enter”

 5.  Type “regsvr32 OpenSTAADUI.tlb”, click “Enter”.  You should see a dialog box appear indicating the file has been registered.

 6.  Launch STAAD.pro and you should not receive the message anymore.

Solution B

Uninstall STAAD.Pro, OPENSTAAD and other STAAD Components (Pipelink, StrucLink) and reinstall them with full administrative privilege.

Question:

During the analysis of a structure suspended from a pivot, Staad reports an instability warning message.

Answer : 

When a structure is suspended from a single point defined as a pinned support, it can swing about that point like a pendulum since a pinned support cannot resist the moments MX , MY or MZ. This is a rigid body motion. Rigid body motions are not handled during static analysis and are reported as an instability condition.

One may assign a weak spring to stabilize the structure rotationally at that support as shown below.

************************************************************************

SUPPORTS

93 FIXED BUT KMX 0.05 KMY 0.05 KMZ 0.05

************************************************************************* 

This should avert the instability condition. Although a moment would be developed at support, its magnitude will be negligible.

Alternatively, additional supports defined at the lower levels that prevent translation along FX and FZ may also be specified as a remedy to this problem.

Note that only the initial position for geometry and loading are considered during this type of linear static analysis. If the structure does rotate as a rigid body at the site, that condition is not being analyzed with the above arrangement.

In the practical scenario, the structure will try to attain a position where the vertical load acts along a vertical line passing through the support so that there will be no eccentricity. That is, the support and C.G coordinates lie on the same vertical line .

Consider the example shown below.

The complete arrangement is being suspended from a single top support. Due to eccentricity of the center
of gravity with respect to the support, the initial loading condition induces an initial rigid body rotation.

If one wishes to avoid using stabilizing rotational springs, the structure has to be analyzed in the equilibrium position.

For this, the eccentricity needs to be determined (the horizontal distance of CG from the X and Z coordinates of the point of suspension). The center of gravity of loading can be found in the output file with the help of the PRINT CG command .

From this data, Θ be computed . Next, rotate the structure by that angle “Θ” , so that the load is aligned with a line passing through the support coordinate. Thus, you are now analyzing the arrangement at the equilibrium position.

Error or Warning Message

When opening STAAD.Pro, the following message can occur:

Unable to activate RSS Feed connection

Explanation

This message indicates that STAAD News Feed cannot be activated successfully. In such situation, STAAD News are not shown in the start-up window of STAAD.Pro.

How to Avoid

1. In most cases, it should be enough to install BentleyRSS.msi file, which can be downloaded from here.

2. If installation of BentleyRSS.msi file does not help, check if you are able to go to the page http://feeds.rapidfeeds.com/8131/ or not. If not, then there is potentially some firewall/security in your network that is blocking the communication when STAAD.Pro is trying to communicate with the RSS feed page.
   
   If you are able to connect to the webpage through Internet Explorer, it means that specifically when STAAD.Pro tries to access information over the internet, that particular communication is being blocked. You may check your firewall settings in your network and add STAAD.Pro (C:\SProV8i\STAAD\Staadpro.exe) to the list of Exceptions. If you have a proxy server in your network then check if that is blocking the communication or not.

The same solution can also be used to correct a problem with the RSS Feed in Ram Manager 14.06 or later.

How can I convert the unit of an existing input file? Say the model has already been set up in metric unit, how can I change it to imperial unit in the input .std file?

First of all, even if you have modeled in metric units, you can still get the data displayed in imperial units. To do that, you just need to go to Tools > Set Current Display Units > and set appropriate units for Structure Units, Section Units, Force Units etc. as needed. The model data will then be displayed graphically in those units. Also to ensure that any data going forward is entered in imperial units, you can go to Tools > Set Current Input Units and set the Length and Force units appropriately.

For Connect Edition version you will find this option under View > Display options as shown below. 

Alternately if changing the actual inputs ( like say Joint Coordinates ) from metric to imperial or vice versa is important for you, you will have to follow a manual process. You can copy the joint coordinate data from the Nodes table from inside Modeling > Geometry page by selecting the table data ( click on the top left corner cell) right click Copy and copy it to excel by right click paste. Standard windows commands like CTRL+A, CTRL+C, CRTL+V will also work for this. Once in excel, you can factor the values for all the cells by the appropriate conversion factors (metric to imperial). The modified data can then be copied from excel. Open the STAAD.Pro editor and first change the UNIT command before the JOINT COORDINATE data to the right units. Replace the old joint coordinates data by pasting the copied data from excel. Be aware of the fact that you may need to insert additional UNIT commands further down the line (inside the command editor) so that the data values are consistent with the unit settings preceding the data.

We highly recommended that you follow the procedure described in paragraph 1 as opposed to what is described in the paragraph 2 unless you are very comfortable using the command editor. Since the process documented in paragraph 2 involves manual changes to be made to the input, it is very easy to make a mistake and thereby end up with inconsistencies between units and input values and so extreme caution should be exercised when going this route.

My model takes a long time to analyze. What can I do ?

Size of the model and number of load cases directly affect the analysis time. So leaving out any detail that is not important for the analysis is something worth considering. For example there may be stairs, handrails, access ladders, monorails, connection components like gusset plates, stiffeners and such other entities that may be left out from an analysis model. Also there may be certain loads/combinations that you may already know will not be governing the analysis/design. Avoid including these in your model, specially if analysis time is a concern. Using a relatively coarser mesh, changing some of the primary loads to reference loads, changing REPEAT LOADs (if any) to LOAD COMBINATIONs (if the analysis is linear one), are some of the other things to try out. Also make sure that you are using the latest STAAD.Pro CONNECT Edition (ver 22.05.00.131 and up ) as that has the faster solver available for all license types (Advanced and Basic). Also last but not the least, if you are trying to run the analysis for a file which is on a network drive, try copying the file to your local machine and see if the analysis time improves. Software performance can be affected significantly by network speed/activities.

Error or Warning Message

Error "LoadLibrary failed with error 126: The specified module could not be found" occurs while clicking on 3D Rendered View icon in STAAD.Pro or while going to Beam -> Stresses tab in the Postprocessing mode.

How to Avoid

a. Click on Start, click All programs, click Accessories, right click on Command prompt and select Run as administrator. 

b. Type in the following commands and hit enter after each command 

      Cd /d C:\Windows\System32

      Copy atioglxx.dll .dll

c. Exit the command prompt and check for the issue.

I have a STAAD.Pro model with connection data defined in it using RAM Connection. I just installed the STAAD.Pro SS6 version 20.07.11.70 and now I cannot open the STAAD.Pro model anymore. The opening process does not complete and I have use Task Manager to eventually end the process. What could be the issue?

STAAD.Pro SS6 comes with the updated version of RAM Connection interface ( v11 ). This new connection interface uses a new schema to save the data which has rendered the older connection data, created using the older version of the connection design interface, incompatible. For this reason one may have problems in opening any STAAD.Pro model with associated connection design data created using previous versions of the RAM Connection design interface.

To resolve this problem, delete all the other files in your model folder except the .std file and any external upt files, if you have any. Open the model using the new STAAD.Pro version and it should now open. The connection data would have to be recreated though.