1. How do I display the deflection diagram and the displacement values on that diagram?
2. After running the analysis, I go to the View menu, select Tables | Node Displacements, and select the load cases for which I want to see the values. The values are displayed in inch units. I want them in "cms" units. Changing the units using Tools | Set Current Unit doesn't seem to make a difference.
3. I want to print out a picture which consists of a truss I have modeled with the STAAD. I want the output forces labeled right on each member. This is very similar to what would be put on to a plan sheet. Can STAAD do this or must I print out a report to get these forces?
4. When I annotate beam moments on my diagrams, I can't seem to 1) change the font by adjusting the Beam Labels option and 2) turn off the unit being written on every single number.
5. Why are my annotations for maximum bending moment or shear values not showing up in the post-processing mode?
6. If I have a moment vector along the local positive Z axis does it have a twisting action going to the right along the positive direction of the axis?
7. What are the sign conventions for moments in a 3-D structure?
8. After performing the analysis, I enter the post-processing mode to view the member end force values. I click on the Beam page on the left side of the screen and see the values listed on the tables on the right hand side. Unfortunately, the moment values are in kip-inch units, even though my current units are set to feet and pounds. What do I have to do to get the values to show up in pound-feet units in the tables?
9. What is the purpose of the Beam - Graphs page on the left side of the screen?
10. How do I display the bending moment diagram and the values on that diagram, or shear forces or Axial forces?
11. When I take a picture, it prints on the top half of a 8-1/2 x 11 size page. How can I take pictures that fill the page?
12. How to insert a company logo into STAAD.Pro report?
13. Can I get STAAD.Pro to report the torsion stress ?
14. How can I have STAAD report more than 3 places of decimal in the post processing result tables?
15. How to know the version of the design code which is being used by STAAD.Pro during the analysis?
16. How to see the displacement of only one particular node graphically?
17. What is the difference between the local and global deflection in the member query box?
18. I am analyzing a large 3D structure. I changed the beta angle of one of the members to 90. I expected the MY and MZ for the two scenarios ( beta =0 and beta=90) to get interchanged. However that does not seem to happen. Why ?
19. How to get Member End Forces for a specific selection of beams?
20. How do I change stress output units in the *.ANL output file? They are coming out as kN/m2. I want N/mm2
21. How do I save a 3D render view (generated by the pyramid' icon)? I am able to do this for other views using View > View Management

1. How do I display the deflection diagram and the displacement values on that diagram?

The first step to viewing these results is to perform the analysis of the model successfully. Select Analyze from the Staad.Pro top menu bar followed by the Analysis option.

A dialog box by the name Select Analysis Engine will appear. Click on the Run Analysis button of this dialog box. After the analysis of the file is completed, click on the Done button.

The next step is to go to the Post Processing mode to view the deflection values graphically. To enter into the Post Processing mode, select Mode from the top menu bar and select Post Processing. Remember that if your analysis is not successfully completed (for reasons such as errors in your input data), you will not be able to access the Post Processing mode.

By default, the deflection diagram always opens up in the post processing screen of Staad.Pro.

From the top menu bar, choose Results - View value. Under Ranges, choose All. (The All button means the deflection diagram will be annotated for all nodes.)

Under the Node tab, you will see the options Global X, Global Y, Global Z and Resultant. Make the appropriate choice. Click on the Annotate button. Then click on the close button.

If you would like to see the diagram annotated for a different load case, select that load case from the load selection box.

2. After running the analysis, I go to the View menu, select Tables | Node Displacements, and select the load cases for which I want to see the values. The values are displayed in inch units. I want them in "cms" units. Changing the units using Tools | Set Current Unit doesn't seem to make a difference.

The unit system in which results are displayed on the tables is set using the facilities available under the View - Options menu. These are known as the display units. To set the display units for the node displacements, please do the following :

In the View menu, select Options - Structure units. In the category called Displacement, select the units you desire and click on OK.

3. I want to print out a picture which consists of a truss I have modeled with the STAAD. I want the output forces labeled right on each member. This is very similar to what would be put on to a plan sheet. Can STAAD do this or must I print out a report to get these forces?

First, you have to ask STAAD to Annotate the drawing with the axial forces. For this, please go to the post processing mode after you have analyzed the structure.

Click on the "Beam" tab on the left side and then click on the sub-tab labeled "Forces."

Click the right mouse button on the screen and select "Structure Diagrams."

From the "Loads and Results" tab, click on "Axial" under the "Beam Forces" heading.

Uncheck the "bending zz" box and click "Apply" followed by "OK."

Maximize the screen and then go to the "Results" pull down menu and select "View Value..."

Click on the "Beam Results" tab and then check the box under the "Axial" heading labeled "Ends."

Click "Annotate" and then "Close."

The axial loading values should be displayed on your screen.

4. When I annotate beam moments on my diagrams, I can't seem to 1) change the font by adjusting the Beam Labels option and 2) turn off the unit being written on every single number.

Annotation labels, although applied to beams, nodes, plates and solids, are not altered by the associated options (i.e View | Options | Beam Labels). In order to change the display of the annotations, go to View | Options from the main menu and choose the Annotation tab. To remove the display of the units for each annotation, simply choose the option "123.4" instead of "123.4 kN" under the Style list box in the Annotation tab. This will write the unit in the bottom right-hand corner of the screen for force, length and moment. If the units are not shown, go to View | Structure Diagrams and choose the Labels tab. Check on the option "Show Diagram Info" under the General box.

5. Why are my annotations for maximum bending moment or shear values not showing up in the post-processing mode?

In order to see the annotation (from Results->View Value in the post-processing mode) for a particular force or moment, the corresponding diagram must be on. For example, if one was to select maximum bending under the Beam Results tab, the bending moment diagram must be on (either MX, MY and/or MZ). Also, under the Ranges tab, make sure that the "None" option is not selected. Obviously, this would not annotate anything if it were selected. As a final note, once the annotations are visible, the size and font can be changed from the Annotation tab under View->Options in the main menu.

6. If I have a moment vector along the local positive Z axis does it have a twisting action going to the right along the positive direction of the axis?

If a member is drawn with its longitudinal axis (local-X) from left to right, and the local Z axis coming out of the page towards you, a positive MZ would cause tension on the top fiber, and a negative MZ would cause tension on the bottom fiber.

7. What are the sign conventions for moments in a 3-D structure?

The sign conventions are as follows:

Axial (FX) : Positive = Along local X axis, Negative = Opposite to local X
axis
Shear-Y (FY) : Positive = Along local Y axis, Negative = Opposite to local Y
axis
Shear-Z (FZ) : Positive = Along local Z axis, Negative = Opposite to local Z
axis

Torsion (MX) : Positive = Along local X axis, Negative = Opposite to local X
axis
Moment-Y (MY) : Positive = Along local Y axis, Negative = Opposite to local
Y axis
Moment-Z (MZ) : Positive = Along local Z axis, Negative = Opposite to local
Z axis

For axial forces,

Positive at the start node indicates compression at the start node.
Positive at the end node indicates tension at the end node.

Negative at the start node indicates tension at the start node.
Negative at the end node indicates compression at the end node.

8. After performing the analysis, I enter the post-processing mode to view the member end force values. I click on the Beam page on the left side of the screen and see the values listed on the tables on the right hand side. Unfortunately, the moment values are in kip-inch units, even though my current units are set to feet and pounds. What do I have to do to get the values to show up in pound-feet units in the tables?

The unit system in which results are displayed on the tables is set using the facilities available under the View - Options menu. These are known as the display units. To set the display units for the bending moments and torsional moments, please do the following :

In the View menu, select Options - Force units. In the category called Moment, select the units you desire and click on OK.

9. What is the purpose of the Beam - Graphs page on the left side of the screen?

This is another way to display the bending, shear and axial force diagrams on the screen.

In the post processing mode, select the Beam page from the left side of the screen. Then select graphs.

The right side portion of the screen will display the Bending diagram (MZ), shear diagram (FY) and the axial force diagram (FX) with values. In the drawing area, if you select a member by clicking on it, MZ, FY and FX of
that member will be displayed on the right hand side. To display the diagrams of another member, select that member.

10. How do I display the bending moment diagram and the values on that diagram, or shear forces or Axial forces?

First you must Analyze the file. Select Analyze from the Staad.Pro top menu bar. Select the Analysis option. After this, click on Run Analysis at the bottom of the small window dialog box.

After the analysis of the file is completed, click on the Done button.

Next, we go to the Post Processing mode to view the forces and results graphically.

To enter into the Post Processing mode, select Mode from the top menu bar and select Post Processing. Remember that if your analysis is not complete, you will not be able to access the Post Processing mode.

By default, the deflection diagram always opens up in the post processing screen of Staad.Pro.

To view the Bending Moment Diagrams, select the Beam page from the left side. From the top menu bar, choose Results - View value. Under Ranges, choose All. (The All button means the Bending moment diagram will be displayed for all members.)

Under the Beam Results tab, you will see the options Bending, Shear, Axial, Displacement and Stresses.
Make the appropriate choice.

Click on the Annotate button. Then click on the close button.

11. When I take a picture, it prints on the top half of a 8-1/2 x 11 size page. How can I take pictures that fill the page? 

There is no direct way to change the size of the picture from within STAAD.Pro. However here are a few options that you may find useful

Option 1

1. Before taking a picture, please ensure that the model is
   zoomed in sufficiently so that it fills up the space within the picture border as far as possible.
2. Take the picture and include that as part of the report using the Report Setup.
3. Go to File > Printer Setup and change the orientation to Landscape.
4. Go to File > Print Preview Report to check whether it looks satisfactory or not and if so, print it.

Option 2

1. You may copy the picture by going to the menu option Edit > Copy Picture. You can then paste the picture in MSWord or Excel or Paint.
2. Adjust the size of the picture using the tools available within these applications and take a print from there.

12. How to insert a company logo into STAAD.Pro report?

1. Open the start-up window of STAAD.Pro and go to the Configuration option.

2. Choose “File Options” tab and tick the “Remove Bentley Logo from Report” box. This will remove the Bentley logo    from your reports

3. Open the STAAD.Pro file. Go to the Report setup page and click on “Name and Logo” option.

4. Go to file option and choose the path where you have stored your logo. The logo should be in .bmp format.

5. Write the company name. You can orient the logo and company name by the Alignment option.

Note, Ram Elements, Connection and Ram Structural System have similar options. For Elements or Connection go to the upper left menu - General Configuration - Print tab. For RAM Structural System you just have to replace the logo.bmp file in the program directory with your own logo.bmp or logo.jpg file. it tends to work best when the log has roughly a 1:1 aspect ratio.

13. Can I get STAAD.Pro to report the torsion stress ?

STAAD.Pro does not report stress due to Torsion but here are a couple of items which you may find useful.

The beam end forces table that you can get from Postprocessing mode Beam > Forces page, reports the torsion ( MX ) in a beam member.

STAAD is also able to account for stresses due to torsion during the design phase. In steel design for example, the torsion stresses are converted to normal and shear stresses and added to existing normal/shear stresses following guidelines laid out in AISC Design Guide 9. When it comes to the new AISC 360-10 code, currently the software can account for the torsion for HSS sections only although work is under progress to account for torsion for Non-HSS sections too and this should be available in a couple of months. 

14.How can I have STAAD report more than 3 places of decimal in the post processing result tables?

You need to go to the top menu and click on View > Options > Choose the appropriate item and change the corresponding number of decimal places as desired > Click Apply > OK.

15. How to know the version of the design code which is being used by STAAD.Pro during the analysis?

The design code version which is being used by STAAD.Pro during the design phase is written in the Output file

16. How to see the displacement of only one particular node graphically?

1. Analyze the model and go to the Postprocessing mode, Node -> Displacements page.
2. If needed, turn on the node symbol (click Shift + K on your keyboard) and node numbers (Shift + N).
3. Go to the Results -> View Value menu.
4. In the Ranges tab select Ranges and enter the node number(s) for which you want to see the displacement.

5. Then go to the Node tab and select Nodal Displacement which you want to see. Click Annotate.

Now the displacement of only selected node will be seen on the screen. Similarly, beam force diagram values, beam maximum displacements, beam combined stresses and support reactions can be set.

17. What is the difference between the local and global deflection in the member query box?

Figures (1) and (2) show the local and global deflections of the beam #2 which is a part of the beam joining 2 columns:

Figure (1) 

Figure (2)

Global deflection is the largest distance between (a) and (b) where:

(a) is the line joining the ends of the member in its un-deflected position (named as 'Original shape' in the figure (3));

(b) is the elastic curve of the member representing its deflected shape.

Local deflection is the largest distance between (c) and (d) where:

(c) is the line joining the ends of the member in its deflected position;

(d) is the elastic curve of the member representing its deflected shape.

Figure (3)

18. I am analyzing a large 3D structure. I changed the beta angle of one of the members to 90. I expected the MY and MZ for the two scenarios ( beta =0 and beta=90) to get interchanged. However that does not seem to happen. Why ?

The Mz and My would not simply get interchanged when you apply a beta angle to 90 for every situation. The same would be true if you are analyzing a beam in isolation without considering any effect from the rest of the structure. However when a beam is part of a bigger structure, the beam’s local stiffness in each direction would affect the global stiffness of the structure along each DOF. Depending on that there will be a redistribution of the forces which will result in different moments/shears.

19. How to get Member End Forces for a specific selection of beams?

The procedure of specifying the commands to report the member end forces is described in STAAD.Pro Help manual chapter 1.5.12:



Alternatively, one can use a Report Setup with specified Ranges (by group or simply typing in the member numbers in the Ranges field):

20. How do I change stress output units in the *.ANL output file? They are coming out as kN/m2. I want N/mm2.

The units of items reported in the analysis output file are based on the unit settings in the input command file ( editor ). The unit that is current at the time the relevant command triggering the output is processed, is used for the reporting. One can set the units appropriately using the editor ( Edit > Edit Input Command File ) as explained next. For example to get the support reactions and member forces reported in Newton and mm units one needs to enter the unit command before the print commands as shown next

…

PERFORM ANALYSIS

UNIT MM NEWTON

PRINT SUPPORT REACTIONS

PRINT MEMBER FORCES

…

Any other output printed in the ANL file following the above commands, would also be printed in the currently set units of Newton and mm.

21. How do I save a 3D render view (generated by the pyramid' icon)? I am able to do this for other views using View > View Management

As of now there is no way to save the 3D rendered view as a Saved View. However here are a couple of options that you may find useful 

1. Right click on the 3D Rendered View and choose the Take Picture option. The picture is then saved and can be accessed from within Report Setup ( File > Report Setup ) and can be included as part of the report.

2. Instead of using a 3D Rendered View, you can plot a full section view ( right click inside the whole structure window and choose Labels > Structure > Full Sections ). This would be similar to the rendered view but the difference is, you would be able to save it through View > View Management

See Also

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

This contains wiki on the AISC code.

STAAD.Pro Model

Relevant STAAD.Pro model (.std file) can be downloaded from the following link:

STAAD.Pro model for AISC 360-10 verification example

Section Details

Overall Dimension (D) = 1500mm

Flange width (Bf) = 250mm

Flange thickness (tf) = 30mm

Thickness of Web (t_w) = 15mm

h= 1500-2*30 = 1440mm

Shear Capacity Calculation

STAAD.Pro Design Output

Important notice regarding version compatibility

Starting with RAM Structural System version 14.06 and Ram Concept version 5.1, both programs are offered as either 32 or 64 bit applications. In order to integrate the two programs using the methods described in this wiki both must be alike in this regard, so be consistent and install the 32 or 64 bit versions of both applications.

On My SELECT CD, the 64 bit versions are labeled with the x64 suffix. The 32 bit versions have no suffix. The 32 bit versions will work on either a 32 bit or 64 bit machine, but the 64 bit versions require a 64 bit operating system.

Embedded RAM Concept files are deleted during file conversion when v14.05 files are opened in RAM Concept for both 32-bit and 64-bit versions in v14.06.00. The problem was resolved in v14.06.01. Users who are running v14.06.00 can work around the problem by doing the following:

1. Open the file in v14.06 and convert the file to the new version format.

2. Open Windows Explorer and find the .zip file with "Orig v14.5" at the end of the file name that is automatically created during the conversion process. Double click on the file. Find the embedded .cpt files. The file name will be same as ram model with .cpt###E at the end. Copy the files to the clipboard.

3. In Windows Explorer, navigate to the working directory (C:\Program Data\Bentley\Engineering\RAM Structural
System\Data\Working). Paste the embedded .cpt files from the v14.5 backup into this folder.

4. Launch RAM Concept from RAM Manager.

Overview

This page is the landing page for user help when integrating RAM Concept models with RAM Structural System. Please use the links below to access the desired help pages. Additional information can be found in the RAM Concept Manual; see Sections "Importing a Database from the RAM Structural System" and "Exporting a Database to the RAM Structural System."

Importing Data from RAM Structural System into RAM Concept

          What Is and Is Not Imported

          Common Errors and Warnings

          Other Considerations

Exporting Data from RAM Concept to RAM Structural System

          What Is and Is Not Exported

          Other Considerations

See Also

Unlinking Ram Concept Files from RAM SS

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Problem Description

XXXXXXX(Provide a complete description of the problem. Should be written in the "first person" [e.g., "When I compute the model�"])XXXXXXX

Steps to Resolve

1. XXXXXXX(add more steps as needed)XXXXXXX

Why are some tendons shown at the wrong elevation in the tendon perspective?

The soffit elevation at each profile point is determined during the Analyze All and Calculate All commands. If one of these commands is not performed since the drawing (or moving, etc.) of a tendon, or since a change in the mesh, the tendon elevations in perspectives are not accurate.

The same is true for elevations optionally shown as text on the plans.

It is quicker to analyze (but not using “Calculate All”) with Process > Analyze All. This avoids processing the design calculations.

How can I place a manual tendon relative to the top surface, rather than up from the soffit?

If you use manual tendons, they can be placed with an elevation relative to either surface or soffit. If you use the "Above soffit" approach and enter say 6.25” for the high points, then high points will stay 6.25” up from the soffit even if the slab thickness changes.

On the other hand, if you use the “Top cover” option with a small positive cover (or if you use the “Above surface” option with a small negative number), then the top of the strand will maintain the distance from the top surface and increasing the slab thickness will result in tendons with more drape.

What do “Latitude” and “Longitude” Tendons mean?

In the USA, Britain and other countries it is typical practice to place all the tendons in one direction in a concentrated band over column lines. If the designer is using another practice then we recommend that you still use the Latitude and Longitude tendon layers because it makes editing the PT easier. i.e. Put the tendons in the X direction on one layer and the Y tendons on the other. Latitude and Longitude are just layer names.

Do I have to draw the tendons for a post-tensioned slab?

Yes. It is not difficult, and encourages you to address detailing issues before they become field problems.

How do I draw tendons?

See Chapter 26 Defining Tendons for details. It's important to note that the program allows you to manually define tendons on the manual tendon layers, or you can generate tendons based on user defined tendon parameters.

Can I harp tendons?

Yes. Any tendon segment can be declared to be harped. The “half-span” tendon tool is useful for any harp point (or any low point) that is not at mid-span. Multiple harp points can be located in any span by using multiple tendon segments.

Does it matter which way I draw “half” tendons?

Yes. The inflection point is measured from the first point clicked and the profiles are specified in the order of the points clicked. To be compatible with the tendons created using the Full Span Tendon tool, we strongly recommend that you always start at the high point.

Can I terminate some strands past a column?

This can be done with one of two methods.

The tendon can be “forked” such that the number of strands decreases. As shown in Figure 37-1, if the transition is from 15S (15 strands) to 10S (because an adjacent span does not require that many strands) then terminate 5S using a half span tendon. It is common to terminate strands at quarter span and at the slab centroid.

Note: You should only use this method for tendons with no jacks attached. This is because a jack attached to tendons of different lengths has inaccurate seating (wedge draw-in) loss calculations.

Figure 37-1 Termination of strands (no jacks)

The second method can be used when jacks are modeled. If the total number of strands is 15S then one tendon with 10S needs to be continuous with an additional tendon with 5S alongside. It is common to terminate tendons at quarter span and at the slab centroid.

Figure 37-2 Termination of strands / tendons (jacked). Plan alignment of tendons is subjective.

Does Concept check to make sure the number of strands in connected tendon segments is consistent?

Yes. you will get a warning to that effect during the calculation when the strand number changes.

How does Concept calculate friction losses?

Concept only calculates friction losses if jacks are specified. Concept performs friction loss calculations considering the (elevation view) curvature of the tendons, the (plan view) horizontal kinks in the tendon and the jacking and friction parameters. The stress in the tendon is assumed to vary linearly along each tendon segment.

Does Concept calculate elongations (extensions)?

Yes, if jacks are specified. Use the Visible Objects dialog to view "Jack Elongation" on the manual tendon standard plans.

Do the elongations (extensions) include the effect of the seating distance (wedge draw-in)?

Yes. The elongation reported includes the deduction of the seating distance.

Why do I get the warning:  "An error has been found.   A non-external tendon is out of a cross section in design strip x-x" 

RAM Concept is checking one of the design sections in that design strip. The particular section has been trimmed. It may have been trimmed due to the cross section trimming method (e.g. using Max rectangle trimming could trim off any beams or drop panels in the section) or because of the slope limit which prevents adjacent sections from rapidly jumping in depth. Where there error occurs, there is a tendon passing through this section within the part of the section that was trimmed off.

To fix the problem either revise the strip trimming methods and/or verify the cross section in perspective view. You may need to revise the design strips in plan or move the tendon in some cases.

See Also

Cross Section Trimming

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Error or Warning Message

During installation, the following error occurs and the program does not install:

Explanation

The new RAM Connection Design Framework required Microsoft.NET Framework 4.5. This program is supported by Windows 8, Windows 7, and Windows Vista. It is not supported by Windows XP. RAM Connection v9.0.0 is no longer compatible with Windows XP.

See Also

[[SELECTsupport TechNotes and FAQs

Following are a list of FAQs related to STAAD.Foundation/ STAAD.Foundation Advanced

1. I have multiple columns which are supported by a single pile cap. How can I model that in STAAD.foundation
2. I modeled a steel structure and want to design pile cap on piles for foundation. Can I import the support reaction from STAAD.Pro. ? Can STAAD.Foundation design this entirely or does it need to be modeled in STAAD.Pro ?
3. When I start up STAAD.foundation, I get a message "SELECT license type is not configured yet. Please run SELECT License Asistant to configure it".
4. I have a problem in staad foundation, the mat foundation is not working only the isolated footing working.
5. When I attempt to do a foundation design I get an error "Error in spacing calculation along length, please check minimum spacing provided". What does the error mean ?
6. I am trying to design a combined footing with 4 supports (all supports). I received an error saying "ALL SELECTED SUPPORTS ARE NOT COLLINEAR AND PARALLEL TO GLOBAL AXIS. CANNOT CREATE COMBINED FOOTING. I checked my supports and all of them are at y=0.
7. I have completed a structural analysis using STAAD.Pro. I need to do some foundation design now and wondering how to get started with it.
8. Does the "Base Pressure Summary for Service Load Conditions" in the calculation sheet show gross bearing pressure or net bearing pressure?
9. I have modeled a mat using plates in STAAD.Pro. How can I get the mat transferred to STAAD.foundation Advanced and design it ?

1. I have multiple columns which are supported by a single pile cap. How can I model that in STAAD.foundation ?

As of now a pile cap, created in STAAD.foundation using the pile cap job type, can only support one column point. If you have multiple columns which are supported by a single pilecap, you will have to create it as a Mat Foundation job and then model the pile cap as a mat. The piles can then be specified under the mat using the Pile spring option.

2. I modeled a steel structure and want to design pile cap on piles for foundation. Can I import the support reaction from STAAD.Pro. ? Can STAAD.Foundation design this entirely or does it need to be modeled in STAAD.Pro ?

Support reactions from STAAD.Pro can be directly taken into STAAD.foundation using the Foundation Design tab within STAAD.Pro and then the pile cap can be designed in STAAD.foundation. For this process there is no need to model pile caps in STAAD.Pro.

If you are asking whether STAAD.Foundation can be used as a standalone application for design of pile caps, then the answer is yes. For that you have to manually enter the column locations and then enter the column reaction loads in STAAD.foundation. If you are modeling the superstructure in STAAD.Pro for analysis, then getting support reactions from STAAD.Pro would spare you the effort of defining the column points and re-entering the loads in STAAD.Foundation and so the process would be a lot faster.

3. When I start up STAAD.foundation, I get a message "SELECT license type is not configured yet. Please run SELECT License Asistant to configure it".

This issue occurs in Windows Vista/7/8 machines, if STAAD.foundation program is not installed with enough administrative privileges.This prevents the registry to be set properly.

To resolve this, right-click on the shortcut for STAAD.foundation in your desktop, and select the option "Run as Administrator". This fixes the registry issue. Next time you can run the program by double-clicking on the shortcut.

To prevent this, when you install STAAD.foundation in Windows Vista/7/8 machine, right-click on the .msi/.exe file and select the option "Run as administrator". This ensures that the resistry is set propely.

4. I have a problem in staad foundation; the mat foundation is not working, only the isolated footing is working.

Please install STAAD Foundation Advanced V8i  in your machine. STAAD.foundation from STAAD.Pro does not support Mat foundation (assuming that you are using STAAD.Pro V8i Build #20.07.08..20 or later version). It
supports only Isolated, combined and Pile cap modules in general mode. To run this STAAD.foundation Advanced module, you must have a license for it.

5. When I attempt to do a foundation design I get an error "Error in spacing calculation along length, please check minimum spacing provided". What does the error mean ?

Most likely the spacing that the software is calculating for your job is coming out to be lesser than the minimum spacing specified.

If you are designing isolated footing, you may go to the Isolated Footing Job > Design Parameters > Concrete & Reinforcement from inside the Main Navigator window and change the Minimum Bar spacing. You may also use higher bar sizes ( Maximum footing bar size ) to allow higher bar spacing.

If you are designing a mat, there is a Design Parameters section witin Mat/Slab analysis/design options, from where you can control the reinforcement spacing. Max spacing and Min spacing are the parameters that you need to play with. You may want to increase the range by increasing the Max spacing and reducing the Min spacing. As before, you may also increase the Max bar size so that the spacing can be increased.

6. I am trying to design a combined footing with 4 supports (all supports). I received an error saying "ALL SELECTED SUPPORTS ARE NOT COLLINEAR AND PARALLEL TO GLOBAL AXIS. CANNOT CREATE COMBINED FOOTING. I checked my supports and all of them are at y=0.

For a combined footing to be created in STAAD.Foundation Advanced, the supports need to follow two conditions

1. The supports need to lie along a straight line
2. The straight line along which the supports lie should be parallel to either Global X or Global Z.

So even if you may have all supports at the same Y elevation, your supports may not satisfy one or more of these criteria, in which case such a message will be provided. For such cases you may use the mat foundation job instead and model the combined footing as a mat.

7. I have completed a structural analysis using STAAD.Pro. I need to do some foundation design now and wondering how to get started with it.

After you run the analysis of the model in STAAD.Pro, you can take the support geometry as well as reactions directly to STAAD.Foundation using the Foundation Design tab from within STAAD.Pro. The steps are explained in the STAAD.Pro software help ( accessed through Help > Contents > Graphical Interface Help > Foundation Design )

In addition we have created a number of video tutorials on different types of foundation and these are available in youtube which you may find useful

http://www.youtube.com/playlist?list=PL5LpElzkNC9lAKMJsmOt5sy_229lqLGlB

8. Does the "Base Pressure Summary for Service Load Conditions" in the calculation sheet show gross bearing pressure or net bearing pressure?

The pressure listed in the Base Pressure Summary table in the calculation sheet is gross pressure. If the user selects the net
bearing capacity input from under Global Settings > Rigid Foundation Settings, the soil bearing capacity input provided by the user is considered as net allowable bearing capacity which is internally converted into gross allowable bearing capacity by the software. The gross bearing pressure values reported in the calculation sheet are then checked against this gross allowable bearing capacity value.

9. I have modeled a mat using plates in STAAD.Pro. How can I get the mat transferred to STAAD.foundation Advanced and design it ?

The steps are listed next

1 Open your STAAD.pro model and run the analysis.  Once the analysis is complete, close STAAD.pro completely.
2.Launch STAAD.foundation Advanced.
3.Click the “Import STAAD.pro” button, shown below:

4.Locate your STAAD.pro file, select it, and click “Open”.
5.You will see the following dialog box appear.  Make sure the “Import Plates” option is selected and then specify the desired code/units:

6.Click “Import”.  You will see your mat appear on screen.
7.You must define a boundary in order for the design to work.  Change the view so you are looking at the mat from a top perspective and click on the “Add Rectangular Boundary” button under the Tools menu at the top of the screen:

If your mat boundary is irregular, you may use the Add Polygonal Boundary option.

8.Click on the upper left hand corner of your mat and then drag down to the lower right hand corner, then release.  You will see the boundary outline appear, as shown next:

9.Go to Mat Foundation Job -> Mesh Generation -> Meshing Setup on the left hand side of the screen:

10.You will see the “Meshing Setup” dialog box appear to the right.  Click on the boundary to select it (it will turn red), then give the region a name and click “Add”:

11.Now you are ready to proceed with the design.  You can commence with the moment envelope generation as you normally would for a mat foundation job type.

A few points to note here are, the analysis of the mat is carried out in STAAD.Pro and the results of the analysis are directly imported in STAAD.foundation Advnanced. That is why no further meshing or analysis are needed in STAAD.foundation Advanced. Also a mat foundation job is created automatically with a slab import and hence that step is not required to be carried out inside STAAD.foundation Advanced.

See Also

[[Structural Product TechNotes And FAQs]]

1. Is it possible to quickly find out the total number of nodes & beams in a model ?
2. How do I stop the Auto Save screen from appearing over and over again in Staad.Pro?
3. How can I define a built up section whose cross section shape is not that of any standard rolled section?
4. I am trying to cut a rectangular hole in an arbitrary triangular region in space which has been meshed with plates. Is there a way to orient the construction grid (for the "snap node/plate" feature) to align with three pre-defined nodes (i.e. the corners of the triangle) to simplify removal of the rectangular feature inside? The angle of the triangle is very odd and I am concerned about the nodes defining the rectangle being slightly out of plane if I try to set the construction grid manually based on the coordinates and angle of the triangle.
5. One issue that I have encountered is that if I go into the load function and realize that I have the wrong units specified, I cannot change the units by going back to the geometry menus and selecting the correct units to use. When I enter the loading menus again, the units have not changed. Is there another way to change the units once you enter the loading functions?
6. When using the foundation support, I am required to give the subgrade modulus and supply a direction. I have always used Y as the direction. However, I am interested in knowing what would occur if I choose Y-only. Is there some type of weak spring placed in X & Z directions, is it completely restrained, or is it somewhere in between?
7. The "View - View Selected Objects Only" option requires two clicks to work.Why ?
8. I am using STAAD.Pro 2004 Build 1004.US also known as the second edition. When I try to add plates using the new feature in the Geometry menu called "Create infill plates", I encounter the message "No closed polygon found to fill in with plates, please check beam selection".What am I doing wrong?
9. I have a rather large frame building consisting of several floors. I want to look at individual floors by themselves without the rest of the structure cluttering up the view. Can you tell me how to do that?
10. How do I access online help in STAAD.Pro? The F1 key does not bring up any help screens.
11. How can I convert single line input to multiple line input? The program currently converts my joint coordinate and member incidence data from multiple line to single line input.
12. How do I merge 2 staad models?
13. I am designing a mat foundation supporting a steel structure. I am applying the column loads as NODAL LOAD. I do not think this is the right approach because I have a base plate that distributes the load over the area of the base plate. How to model this ?
14. Can one create a user defined grid system in STAAD.Pro?
15. I get a warning message during analysis saying *WARNING- APPLIED SELFWEIGHT IS MORE THAN TOTAL WEIGHT OF ALL STRUCTURAL ELEMENTS IN LOAD CASE    113 ALONG Z. What does this mean ?
16. I am modeling a steel building with braced frame (OBF). I want the braces to carry lateral loads only and not the gravity loads. How can I do that ?
17. I have to deal with relatively big model with approximately 50000 plates. However processing is very slow. Are there any limitations on number of plates?
18. How to assign offsets to the plate elements?
19. If we have some beams connecting to a perpendicular beam, should that perpendicular beam be split at the junction of the other beams or that beam can be merged into a single beam?
20. There is a property named Ct that I see within the W shape table of the AISC steel section database. What does this stand for ?
21. After I import the model from the Structure Wizard, it will only create 1 node and there would be a pop up saying that the duplicated nodes and beams are ignored. Why is this happening?
22. If a diaphragm is modeled using plates, will it simulate a flexible or a rigid diaphragm ?
23. In the past when I hovered over the beams or nodes, I was able to see lot of information like node numbers, displacements, coordinates for nodes and beam numbers, properties, end forces, ratio for beams. Now I only see the node and beam numbers. How can I get back the old setting ?

1. Is it possible to quickly find out the total number of nodes & beams in a model ?

Yes. On the left side of the screen, click on the Setup page. On the right side of the screen, click on the button called "More".

Another place to get this from is the button that looks like a question mark. It is called Info. See the figure below.

2. How do I stop the Auto Save screen from appearing over and over again in Staad.Pro?

From the File menu of the main program screen, select "Open Backup Manager".

The dialog box that comes up has a facility to turn off the Autosave feature as seen in the next figure.

3. How can I define a built up section whose cross section shape is not that of any standard rolled section?

You have to specify its properties using the User Table-General section. You can find the details in section 5.19 of the Technical Reference Manual as shown next. Refer to the section titled General

 

4. I am trying to cut a rectangular hole in an arbitrary triangular region in space which has been meshed with plates. Is there a way to orient the construction grid (for the "snap node/plate" feature) to align with three pre-defined nodes (i.e. the corners of the triangle) to simplify removal of the rectangular feature inside? The angle of the triangle is very odd and I am concerned about the nodes defining the rectangle being slightly out of plane if I try to set the construction grid manually based on the coordinates and angle of the triangle.  

Using STAAD's graphical tools, it is quite difficult to insert an opening after the plate has been meshed, unless your plate elements are aligned in a manner that exactly matches the boundary of the opening. The process is far less painful if the hole is specified before the meshing process commences. To do that, please have a look at the solution described later in this section under the topic "Generation of a plate element mesh for an irregular slab with holes/openings"

Alternatively, you may use Parametric Models option as described in section 2.3.6.11 titled Geometry | Create Parametric Models

5. One issue that I have encountered is that if I go into the load function and realize that I have the wrong units specified, I cannot change the units by going back to the geometry menus and selecting the correct units to use. When I enter the loading menus again, the units have not changed. Is there another way to change the units once you enter the loading functions?

From the Edit menu, choose Edit Input Command File. Scroll down till you see commands like

LOAD 1

or

LOAD 2

Prior to the load case which has the units error, add the appropriate unit as shown

UNIT POUND FEET

For example

UNIT KIP FEET
LOAD 1
SELF Y -1.0
MEMBER LOAD
1 TO 25 UNI GY -0.2
UNIT POUND
LOAD 2
JOINT LOAD
33 FX 400
UNIT KNS METER
LOAD 3
MEMBER LOAD
45 UNI GY -3.0

6. When using the foundation support, I am required to give the subgrade modulus and supply a direction. I have always used Y as the direction. However, I am interested in knowing what would occur if I choose Y-only. Is there some type of weak spring placed in X & Z directions, is it completely restrained, or is it somewhere in between?

If X or Y or Z is specified for direction, then,

a) a spring support is generated in that direction
b) the other two translational directions are fully restrained
c) the associated rotational degre of freedom is fully restrained
d) the other 2 rotational degrees of freedom are treated as unrestrained

Example :

plate-list PLATE MAT DIR Y SUBGRADE 0.4

FX is fixed
FY gets a spring
FZ is fixed
MX is free
MY is fixed
MZ is free

If XONLY or YONLY or ZONLY is specified, then, a spring support is generated in that direction. All the remaining 5 degrees of freedom are treated as unrestrained.

Example :

plate-list PLATE MAT DIR YONLY SUBGRADE 0.4

FX is free
FY gets a spring
FZ is free
MX is free
MY is free
MZ is free

7. The "View - View Selected Objects Only" option requires two clicks to work.Why ? 

This error was present in the American edition of STAAD.Pro 2004 Build 1004. For finding the Release and build number, go to Help - About STAAD.Pro. It has been corrected in Build 1005.US.REL. In case you still need to use the version that had the problem, you could do the following to get around the problem :

a) Go to the View menu and choose "View Selected Objects Only" again.

b) Click the right mouse button, choose "New View" followed by one of the 2 options it offers.

8. I am using STAAD.Pro 2004 Build 1004.US also known as the second edition. When I try to add plates using the new feature in the Geometry menu called "Create infill plates", I encounter the message "No closed polygon found to fill in with plates, please check beam selection".What am I doing wrong?

This was an in build 1004 and has been rectified in the US Build 1005. If you need to use build 1004, you can use the same facility from its icon which is shown below.

9. I have a rather large frame building consisting of several floors. I want to look at individual floors by themselves without the rest of the structure cluttering up the view. Can you tell me how to do that?

Method 1 :

a) Orient the view of your model in such a way as to make it convenient to extract using a mouse, the portion you want to view separately. This can be done from View | Orientation, or by clicking on the icons available for this.

b) From the select menu, select the Geometry cursor. Then, using your mouse,create a window around the region you wish to view. That region will be highlighted.

c) Click the right mouse button and select New View. Or, from the View menu, select New View. Set the button on "Create a new window for the View", and click on OK.

The region will now be displayed in a separate window. Once in this window, you can change the viewing angles using View | Orientation, or through the orientation icons, or simply by pressing the up, down, left or right arrow keys on the keyboard.

Method 2 :

This method involves cutting a section using the Tools - Cut section option. Details are available in Section 2.3.4 of the STAAD.Pro Graphical Environment Manual, which can be accessed from Help - Contents.

10. How do I access online help in STAAD.Pro? The F1 key does not bring up any help screens.

The F1 key for help is currently not operational in STAAD. We are working on implementing this for one of the forthcoming releases.

To obtain online help in STAAD, you can do one of the following:

From the Help
menu, if you click on Contents, if will bring up all the STAAD manuals. You can search for specific information, or go through the topic list to select the items you want.

From Help, if you click on Multi Media help, it will bring up a set of movies which will explain the procedure for creating a
model.

If you click on the Start button on your Windows desktop, select Programs, choose STAAD.Pro 2001 followed by STAAD.Pro Online
Documentation, it will bring up the same set of information as the one you can access from step (1) above.

11. How can I convert single line input to multiple line input? The program currently converts my joint coordinate and member incidence data from multiple line to single line input.

 Start STAAD.Pro. Select File - Configure.

Click on the tab called Input File Format

If you want Single line format, switch on the check boxes. If you want Multiple line format, keep them "unchecked".

Click on Accept.

Then from the File menu, open your STAAD input file. When you Save the file from the Graphical screen, the data will be saved in the format you chose in the step above.

12. How do I merge 2 staad models?

Start STAAD.Pro. Open the first file. Keep it open.

STAAD another instance of STAAD.Pro. Open the second file. Stay in this file.

Go to the Select menu, and Select All Geometry. From the Edit menu, select Copy.

Go back to the screen of the first file. From the Edit menu, select Paste.

You will be prompted to specify the X, Y and Z distances by which to move the structure of the second file before it gets copied to the first structure. Specify those values and click on OK.

13. I am designing a mat foundation supporting a steel structure. I am applying the column loads as NODAL LOAD. I do not think this is the right approach because I have a base plate that distributes the load over the area of the base plate. How to model this ?

There are a couple of things you can do.

1.Instead of applying the load as a concentrated point load, try applying the load as a pressure loading on the plates.

OR

2.You may define dummy members ( having high E and zero density ) between the point of application of the concentrated load and the neighboring plate nodes which would help in distributing the load over a wider area.

14. Can one create a user defined grid system in STAAD.Pro?

Yes, a user defined grid system can be created. You need to go to Geometry menu and select Snap/Grid Node -> Beam. Snap Node/Beam window will appear:

Click on the Create button and this window will appear:

You will need to provide a Grid name, select Grid type (Linear, Radial or Irregular) and set various other options. Once this is done, click OK and created Grid name will appear in the list. Check the box near it to activate that Grid.

As new grids are added or modified, the information is stored in the STAAD.Pro data folder with a GRD extension that allows other STAAD files to re-use these defined grids.

You can also import Grids from the DXF file or Grids previously defined in another STAAD.Pro model by clicking on the Import button. The latter import option opens a browse dialog box to identify a GRD file created by the Snap Node Grid tool. Note that GRD files are only created by STAAD.Pro 2007 (or later).

More information can be found in the STAAD.Pro Help (go to Help -> Contents) chapter AD.2007-1001.1.2 Enhanced Grid Tool.

15. I get a warning message during analysis saying *WARNING- APPLIED SELFWEIGHT IS MORE THAN TOTAL WEIGHT OF ALL STRUCTURAL ELEMENTS IN LOAD CASE    113 ALONG Z. What does this mean ?

First a bit of a background as to why this message was introduced and then the reason for the message. STAAD now support a LIST assignment for selfweight command which it did not in earlier versions. After this was introduced, it was found that many times selfweight was not being assigned to all members by users or sometimes selfweight for few members were being accounted for multiple times due to erroneous assignment on part of the user. A check was therefore introduced in STAAD to warn the user of such scenarios. So what the software does is,

a. It finds out the total selfweight ( UNFACTORED ) of the structure ( say X )
b. It finds out all instances of selfweight command used in each case and checks the associated LIST of members and adds these weights up for each member to arrive at a value of selfweight (UNFACTORED) for each case ( say Y ). While doing this, it ignores any factor applied to the selfweight.

For example, let us consider the following example load cases

LOAD 1
SELFWEIGHT Y -1
…

LOAD 6
SELFWEIGHT Z -2.015
…

LOAD 10
SELFWEIGHT Z -1
…

LOAD 113
REPEAT LOAD
1 1.603 6 1.5 10 0.003
…

The load case 6 and 10 both has selfweight assigned to all members in Z.

So when it comes to load case 113, the software checks and finds that selfweight command has been applied in Z direction to all members as part of load case 6 ( it ignores the factor 2.015 ) and then the selfweight has been applied in Z direction to all members as part of load case 10. It ignores the 1.5 and 0.003 factors applied to the selfweight as part of the REPEAT LOAD. Hence for load case 113, the total unfactored selfweight is applied twice to all members and so the Y comes out to be more ( twice in this case) than X. Whenever Y does not match X, the software flags these as warnings.

Now it does NOT mean that there is an error in the analysis. It is just that the software is trying to make the user aware of the scenario by providing these warnings. For this case, one may simply ignore these warnings.

16. I am modeling a steel building with braced frame (OBF). I want the braces to carry lateral loads only and not the gravity loads. How can I do that ?

This can be achieved by making the bracing members inactive for the gravity load cases and re-activating them for the lateral load cases. The INACTIVE specification for beam members is available within General > Spec page. You can find more details on inactive specification within section 5.18 of the technical reference manual. There is also an example 4, demonstrating how to use the INACTIVE specification, which can be found within Help > Contents > Application Examples. The corresponding .std file is provided with the software and can be found within the folder X:\SProV8i\STAAD\Examp\US where X represents the drive in which STAAD is installed.

17. I have to deal with relatively big model with approximately 50000 plates. However processing is very slow. Are there any limitations on number of plates?

The limits on the number of entities, loads etc are outlined in section 5.2 of the Technical Reference Manual. From our experience, it is best if you can restrict your model to 30000 nodes and 30000 beams + plates. Although theoretically it is possible to analyze much bigger models ( Number of Members, Plates and Solids = 225000 ), however from a practical standpoint, it is better to restrict the model to the size mentioned above because for larger models, displaying loads or even navigating through the program's GUI can be quite slow and tedious. Also postprocessing can be very slow and sometimes some of the postprocessing results may fail to load in memory, if the data files are too large. So due to these limitations, we recommend keeping the model size smaller whenever possible.

18. How to assign offsets to the plate elements?

The plates can be moved by the offset distance and connectivity with other plates (beams) should be retained through the use of extremely rigid "link" members. These members are specified with a material having very high modulus of elasticity and low density which ensures the members transfer load, but do not contribute any weight to the structure. 

19. If we have some beams connecting to a perpendicular beam, should that perpendicular beam be split at the junction of the other beams or that beam can be merged into a single beam?

Forces between the beams (or other elements) in STAAD.Pro can be transferred only through the common nodes. If some beams do not intersect with other beam members, you need to split those beams in order to have common nodes with other beams, so that the forces could be transferred correctly.

You can quickly intersect members by selecting all members and going to Geometry -> Intersect Selected Members -> Intersect.

20. There is a property named Ct that I see within the W shape table of the AISC steel section database. What does this stand for ?

The Ct parameter is applicable only for T shapes being cut from W shapes. The parameter denotes the distance of the cg of the T section ( cut from the W shape ) from the flange as shown in the diagram below.

21. After I import the model from the Structure Wizard, it will only create 1 node and there would be a pop up saying that the duplicated nodes and beams are ignored. Why is this happening?

2 things should be checked:

1)  Go to the View -> Options menu and select line Tolerance in the opened window. Make sure that the Tolerance value is entered as 0.01 inches (or 0.001 meters). If this value is much higher or entered as 0, change it to 0.01.

2) Open the Structure Wizard and go to File -> Select Units. Make sure that selected units are the same as in the main STAAD.Pro model.

*Note: in order to change the Tolerance value, make sure that you have full read/write privileges to the file StaadPro20070.ini which is located in (for STAAD.Pro SELECTseries 4):

Windows XP OS: C:\Documents and Settings\All Users\Application Data\Bentley\Engineering\STAAD.Pro V8i SS4\

Windows 7/8 OS: C:\ProgramData\Bentley\Engineering\STAAD.Pro V8i SS4\
 

This file can be located in different folder for older STAAD.Pro versions.

22. If a diaphragm is modeled using plates, will it simulate a flexible or a rigid diaphragm ?

When one defines a plate, the actual thickness of the diaphragm is modeled through plate thickness definition. So the true stiffness of the slab is considered in the analysis and diaphragm shears are distributed accordingly. If the thickness is small, the diaphragm would behave more like a flexible diaphragm and similarly as thickness is increased, the slab would tend to behave like a rigid diaphragm.

The software does not idealize the diaphragm as rigid or flexible. However you can always compare the maximum lateral deflection of the diaphragm to the average lateral drift of the adjacent vertical elements and thereby classify it, if you need to.

23. In the past when I hovered over the beams or nodes, I was able to see lot of information like node numbers, displacements, coordinates for nodes and beam numbers, properties, end forces, ratio for beams. Now I only see the node and beam numbers. How can I get back the old setting ?

You need to go to the top menu and choose View > Structural Tool Tip options and you will find a number of check boxes using which you can turn on the items that you want to be displayed.

24. In my structure the load transfer does not appear to be as per expectation. What could be wrong ?

Generally these can happen due to modeling issues. Some of the common modeling problems arise from improper connectivity between members/elements or from application of releases/truss specifications which in turn leads to zero stiffness/instabilities.

To view documents related to connectivity issues between elements and how to fix these, please click here. To find out more on Zero stiffness and Instabilities in the model please clickhere.

See Also

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Link

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Couple of comments:

Q. How do I stop the Auto Save screen from appearing over and over again in Staad.Pro?

Proposed "solution" is not an answer to the question. The users want to know how to stop the  Auto Save screen popping-up endlessly, not how to turn off auto safe feature.

Q. How do I merge 2 staad models?

First of all - suggested technique does not work - error message "Multiple entities cannot be copied on the clipboard" appears after Edit/Copy. Second - the question is quite clear - "How do I merge 2 staad models", not "How do I merge geometry". Model is much more that just geometry and includes specifications, loads, load combinations, units, groups, etc.

What is the Working directory?

A RAM Structural System model file (e.g. filename.rss) is literally a WinZip 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).

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] . 

Are RAM Structural System models backwards compatible?

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 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.

When I open a model I get a warning, “This file appears to be currently opened by: User Name…”.

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.

When I open a model I get a warning, “A temporary backup file has been found for this database (path to file), which indicates that the program abnormally terminated…”. 

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.

When I open a model I get a warning, “Could not delete RAM model: filename. Working files in directory \path to working directory\, please use the explorer to delete these files.”

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.

When attempting to load a module, I receive a message that a file with a db.sdf extension already exists.

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:

1. Open the Control Panel from the Windows Start menu (Windows XP/Vista/7) or Windows Start screen (Windows 8).
2. Open Add or Remove Programs (Windows XP) or Programs and Features (Windows Vista/7/8).
3. If running RAM Structural System 14.06.00 or earlier, remove Microsoft SQL Server 2005 Compact Edition. If running RAM Structural System 14.06.01 or later, remove either Microsoft SQL Server Compact 4.0 or Microsoft SQL Server Compact 4.0 (x64).
4. Locate and open the RAM Structural System installer (e.g. ramm14060100en.exe or ram6414060100en.exe), often stored in the Downloads folder.
5. Click the Install button next to Microsoft SQL Server Compact Edition, and proceed through the installation to restore the component.

Something is wrong with my model file, is there an automatic backup?

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”.

How can I reduce the size of my files?

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:

• Include the RAM Frame Wall Forces results
• Include other RAM Frame Analysis results
• Include RAM Concrete Analysis results
• Include the RAM Concrete Column Interaction Surfaces
• Include the RAM Concrete Shear Wall results.

See Also

RAM Defaults Guide [TN]

RAM Table Editing [FAQ]

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

STAAD.Pro Model

Relevant STAAD.Pro model (.std file) can be downloaded from the following link:

STAAD.Pro model for Bending Capacity Check

Section Details

Overall Dimension (D) = 820mm

Flange width (Bf) = 200mm

Flange thickness (tf) = 10mm

Thickness of Web (t_w) = 6mm

h = 820-2*10 = 800mm

Section Class :

Flange class : Semi-compact

Web class : Slender

Overall Class : Slender

Moment Capacity Check 

The member is laterally supported (LAT 1) and welded section (STP 2). FYLD is specified as 345 N/mm².

STAAD.Pro Design Output

This contains wiki on the IS:800 2007 code.

• Section Classification of Laterally unsupported ISMB section

• Slenderness Check of Laterally unsupported ISMB section

• Tension Capacity Check of Laterally unsupported ISMB section

• Compression Capacity check of Laterally unsupported ISMB section

• Shear Capacity Check of Laterally unsupported ISMB section

Is there a way to add a node or connect two members that are crossing each other?

Select the two crossing or nearly crossing members. Then use Process - Segment selection to introduce a node at the intersection point.  Be sure to check the box that indicates, "Add intermediate nodes at memebr intersections"

There is a tolerance for this that you can control.

There is a similar option in the automatic meshing under Process - Analysis - Finite Element Model tab.

In cases where you have crossing members that should slip past each other, this option should be turned off.

See Also

RAM Elements - View Control FAQ

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

The following TechNotes and FAQs are provided as a reference by Bentley's Technical Support Group.

Licensing & Installation

• Configuring Structural Products For SELECT Server
• Accessing SELECTservices Online And Downloading Files
• Manually Removing Bentley IEG Licensing Software
• Viewing And Checking In Licenses Using The Site Administration Page
• [[Using Bentley Structural Products Offline]]
• [[Structural Products Compatibility With 64 Bit Operating Systems]]
• [[Non-Interactive Installation Of Structural Products]]
• [[Performing A Clean Installation]]
• [[Structural Products Licensing FAQ]]
• [[Recommended Computer Specifications For Structural Products]]
• [["Another installation is already in progress, you must complete the installation first"]]
• Why do RAM Structural System modules open in trial mode?

 

STAAD.Pro

• STAAD.Pro TechNotes and FAQs 

 

STAAD.Offshore

• STAAD.Offshore Technotes And FAQs

STAAD(X)

• STAAD(X) TechNotes and FAQs

 

STAAD(X) Tower

• STAAD(X) Tower TechNotes and FAQs

 

STAAD Foundation Advanced

• STAAD.Foundation Technotes and FAQs

 

RAM Structural System

Release Notes and New Issues

• RAM Structural System Release Notes
• Known Issues in RAM SS v14.06.00

TechNotes and FAQs

General

• [[RAM SS - Modules Overview]]
• RAMSS Installation FAQ
• RAM Defaults Guide
• RAMSS Files FAQ
• RAM SS File-Open Troubleshooting [TN]
• RAM Table Editing
• RAM SS 3D Viewer FAQ
• RAMSS Polygon Intersection Error
• RAM SS Analysis Types
• RAMSS Two Way Decks
• RAMSS Common Framing Table Errors
• New Workflow for tables in RAM Structural System Version 14.06

RAM Modeler

• RAMSS Modeling FAQ
• RAM SS Walls FAQ
• Importing DXF Files into RAM SS

RAM Steel

• RAMSS Gravity Loads FAQ
• RAMSS Beams FAQ
• RAMSS Joists FAQ
• RAMSS Columns FAQ

RAM Frame

• RAM Frame Troubleshooting
• RAMSS Eigenvalue Error
• RAM Frame Meshing and Segmentation
• RAM Instability In Finite Element Analysis
• RAM Frame P-Delta
• RAM SS Semirigid Diaphragms
• RAMSS Pseudo Flexible Diaphragms FAQ
• [[RAM Frame - Building and Frame Story Shear]]
• RAMSS Truss Modeling And Design
• RAMSS Wind Loads FAQ
• RAMSS Seismic Loads FAQ
• RAMSS Dynamic Modal Analysis FAQ
• RAMSS Tension Only FAQ
• Star Seismic Buckling Restrained Braces
• CoreBrace™ Buckling Restrained Braces
• RAM Frame AISC 360 Stability Analysis and Design

RAM Concrete

• RAM Concrete Beam [FAQ]
• Wall Boundary Element Design in RAM Structural System [TN]
• RAM Concrete Shear Wall Verification - Planar Wall Using ACI 318

RAM Foundation

• RAM SS - Foundation [FAQ]

Revit Link

• RAM Structural System Revit Link

RAM DataAccess

• What is RAM DataAccess?

RAM Elements

NOTE: RAM Advanse is now RAM Elements

Release Notes

• RAM Elements Release Notes

TechNotes and FAQs

• RAM Elements Importing from RAM SS FAQ
• RAM Elements - View Control FAQ
• Ram Elements - Modeling FAQ
• RAM Instability In Finite Element Analysis
• Creating custom elements in RAM Elements
• RAM Elements Load Combos FAQ
• Ram Elements Shells FAQ
• RAM Elements Masonry Wall FAQ
• RAM Elements Unbraced Lengths
• RAM Elements Effective Length Factors
• RAM Elements AISC Stability
• RAM Elements Dynamic Modal Analysis FAQ

RAM Connection

Release Notes

• RAM Connection Release Notes

TechNotes and FAQs

• [[RAM Connection is installed, but the Connection button fails to appear in RAM Elements]]
• RAM Connection Capabilities and Modeling FAQ
• Troubleshooting Errors when Assigning Connections
• RAM Connection Stalls When Assigning Base Plate Connection
• Catastrophic Failure Error when Using Customized Anchor Position
• RAM Connection Extended End-Plate Moment Connections (MEP)
• Tips for Using RAM Connection within STAAD.Pro [TN].
• How to Customize a RAM Connection Template in STAAD.Pro

RAM Concept

Release Notes

• RAM Concept Release Notes

TechNotes and FAQs

• RAM Concept-RAM Structural System Integration TN
• Modeling Podium Slabs TN
• RAM Concept T-Beams and Axial Force TN
• RAM Concept Lateral Self Equilibrium Analysis TN
• RAM Concept Design Strips TN
• RAM Concept Punching Shear Checks [FAQ]
• RAM Concept Load History Calc Options TN
• [[RAM ConceptCapabilities and ModelingFAQ|RAM Concept Capabilities and Modeling FAQ]]
• RAM Concept Files FAQ
• RAM Concept Plans And Perspectives FAQ
• RAM Concept Structure FAQ
• RAM Concept Tendons FAQ
• RAM Concept Reinforcement [FAQ]
• RAM Concept Loading FAQ
• RAM Concept Shear Reinforcement FAQ

Multiframe

• General FAQS

Maxsurf

Structural Modeler
PowerStructural Modeler
Structural DocumentationCenter

• Technotes have been moved to Structural Drafting and Detailing

See Also

Product TechNotes and FAQs

External Links

STAAD.Pro from Bentley

Structural Analysis and Design Products 

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

This page contains the RAM Structural System V8i - Release 14 Tutorial.

There is a problem with some of the older web pages since or site was updated, including the Ram Tutorial. It should be accessible as a pdf from Start - All Programs - Bentley Engineering - Ram Structural System - Manuals -RamTutorial.pdf.

Disclaimer

The software and related documentation, including this documentation, are protected by both United States copyright law and international treaty provisions. Any unauthorized copying or reproduction is strictly prohibited and subject to civil and criminal penalties. Please refer to the License Agreement for authorization to make a backup copy of the software. You may not sell this software or documentation or give copies of them away to anyone else.

Except as expressly warranted in the License Agreement, RAM International disclaims all warranties, expressed or implied, including but not limited to implied warranties of merchantability and fitness for a particular purpose, with respect to the software, the accompanying written materials, and any accompanying hardware. All results should be verified to your satisfaction. The contents of these written materials may include technical inaccuracies or typographical errors and may be revised without prior notice.

Table of Contents

1. RAM Structural System Outline Tutorial
   1. RAM Manager
   2. 3-D viewer
   3. RAM Modeler
   4. RAM Steel Beam Design
   5. RAM Steel Column Design
   6. RAM Frame
   7. RAM Concrete
   8. RAM Foundation
   9. Links with Other Programs
2. RAM Manager Tutorial
   1. Model Status lights
   2. Selecting Criteria
      
      1. Live Load Reduction
      2. Self ­ Weight Options
   3. Selecting Tables
      
      1. Selecting Units
      2. Additional Commands
      3. RSS Feeds
3. RAM Modeler Tutorial
   1. Floor Layout Type
   2. Grid Layout
   3. Concrete Beam and Column Section Properties
   4. Concrete Column Layout
   5. Concrete Wall Layout
   6. Copy Floor Types
   7. Concrete Beam Layout
   8. Steel Column Layout — Lower Levels
   9. Moving and Sloping Columns
   10. Steel Beam Layout ­— Lower Levels
   11. Steel Member Layout ­— Typical Level
   12. Steel Joist Layout ­— Roof
   13. Slab Edge
   14. Slab Opening
   15. Floor Slabs and Deck
   16. Story Data
   17. Sloping the Roof
   18. Construction Grids
   19. Defining Loads
   20. Applying Loads
   21. Steel Beam Size Restrictions
   22. Brace Points
   23. Web Openings
   24. Layout Bracing
   25. Assigning Lateral Member Sizes
   26. Assign Frame Numbers
   27. Frame Fixity
   28. Wall Openings
   29. Layout Foundations
   30. Renumber Members & Data Check
4. RAM Steel Beam Design Tutorial
   1. Selecting a Floor type
   2. Design Codes
   3. Design Criteria
   4. Design and Investigation
   5. Reports
5. RAM Steel Column Design Tutorial
   1. Brace Points and Splice Levels
   2. Design Criteria
   3. Column Design and Investigation
   4. Copy and Clear User Sizes
   5. Reports
6. RAM Frame - Analysis Tutorial
   1. RAM Frame Basics
   2. General Analysis Criteria
   3. Diaphragm Criteria
   4. Ground Level
   5. Redundancy Factors
   6. Assign Menu Options
   7. Mass and Exposure
   8. Wind Load
   9. Seismic Load
   10. Analysis
   11. View/Update
   12. Member Forces
   13. Deflected Shape
   14. Mode Shape
   15. Drift
   16. Reports
   17. Load Combinations
7. RAM Frame - Shear Wall Analysis Module Tutorial
   1. Section Cuts
   2. Reports
8. RAM Frame Steel - Standard Provisions Tutorial
   1. Design Criteria
   2. Member Code Check ­— Standard Provisions
   3. Joint Code Check ­— Standard Provisions
   4. Reports ­— Standard Provisions
9. RAM Frame Steel - Seismic Provisions Tutorial
   1. Assign Frame Type
   2. Member Code Check ­— Seismic Provisions
   3. Joint Code Check ­— Seismic Provisions
   4. Reports ­— Seismic Provisions
10. RAM Frame - Drift Control Tutorial
    1. Defining Virtual Load Cases
    2. Defining Load Pairs
    3. Reports
11. RAM Concrete Analysis Tutorial
    1. Concrete Program Organization
    2. Concrete Gravity Analysis Module
    3. Concrete Beam Design Module
    4. Concrete Column Design Module
    5. Assign Beam Line Numbers
    6. Analysis Criteria
    7. Other Criteria
    8. Gravity Analysis
    9. On-Screen Results
       
       1. Results ­— Finite Element Model information
       2. Results ­— Vertical Reactions
       3. Results ­— Member Forces
    10. View Options
        
        1. View Beam Lines
        2. View Gravity Loads
    11. Reports
12. RAM Concrete Beam Tutorial
    1. Beam Design Criteria
    2. Detailing Defaults
    3. Load Combinations
    4. Design All and View/Update
    5. Concrete Beam Deflection
    6. Copy Design
    7. Reports
13. RAM Concrete Column Tutorial
    1. Column Design Criteria
    2. Assign Bar Patterns
    3. Design All and View/Update
    4. Copy Design
    5. Reports
14. RAM Concrete Shear Wall Tutorial
    1. Concrete Shear Wall Criteria
    2. Wall Design Groups
    3. Assign Section Cuts
    4. Create and Assign Bar Pattern Templates
    5. Manual Reinforcement and Special Boundary Elements
    6. Generate Load Combinations for Design
    7. Design Wall Design Group 1
    8. Modifying the Design
15. RAM Foundation Tutorial
    1. RAM Foundation Basics
    2. Optimization Criteria
    3. Assign Soil Capacity
    4. Assign Base Plate Sizes to Lateral Columns
    5. Assign Geometry
    6. Assign Surcharge
    7. Assign Pile Geometry
    8. Load Combinations
    9. Design All and View/Update
    10. Reports

How to download software form Bentley Select site?

Follow the steps mentioned below:

1. Click on the following link:

http://selectservices.bentley.com/en-US/

2. The Select Services page will open. Click on the “Software Downloads” option.

3. At this point you will be prompted to log in. Provide your login details and click on “Sign In”.

4. Select the product from the drop down list. For example, if you want to download STAAD.Pro or STAAD.Foundation, select “STAAD Products” from the drop down list. Also select the time period and click on Search button.

5. Check the checkbox beside the product that you want to download. For example, check the checkbox beside STAAD.Pro to download this software and then click on “Continue” button.

6. Select the delivery method and click on “Continue” button.

7. Click on the “Accept” button.

8. In the final page, select the “Download” option to download the software normally. You can also use the “Advanced Download Manager” option.

1. Since the STAAD Offshore loads already include a static component should the static (gravity) loads in the STAAD Pro load combinations be excluded when analysing for  transportation cases?
2. Can we specify Marine Growth above the Still Water Level in STAAD.Offshore?
3. When I generate the STAAD file with wave loads using the STAAD.Offshore module, the file throws up errors while opening in STAAD.Pro and the Wave Load Cases are messed up.
4. I have specified the added mass coefficient and the drag coefficient as zero. However, STAAD is still generating Wave Loads in the Vertical direction.
5. When I try to open my staad.pro model in offshore, I receive the error: “Structure file has syntax errors. check the <filename>.err file for reasons”. What is the cause of this error ?
6.  I added a section to the STAAD.Pro section database and used it in my model. Now I am trying to open the STAAD.Pro model in STAAD.Offshore and I am getting error messages saying “structure file has syntax errors”. How do I get Offshore to recognize my defined sections ?
7. Is it possible to specify the heave + roll and heave –roll in the same load case?

1.Regarding the Transportation module in STAAD Offshore, there is a Gravity/Tilt option on the Transport Definition/General page. When this is turned on it appears that STAAD Offshore generates static load components in the vertical and horizontal directions based on the tilted position of the structure on the ship. These static components are included in the overall inertia loads and transferred into STAAD Pro. Our question is: since the STAAD Offshore loads already include a static component should the static (gravity) loads in the STAAD Pro load combinations be excluded when analysing for  transportation cases? If they are included it appears that we are "double-dipping" on the static loads and resultant vertical loads are too high.

When you are analyzing with the transport loads in STAAD.Pro, you need not consider the self-weight loads separately in the load combinations because you have already considered the inertia force due to acceleration due to gravity in the STAAD.Offshore Module, which is the selfweight of the structure. This is in addition to the inertia force generated due to acceleration of the barge on which the structure is being transported.

2. Can we specify Marine Growth above the Still Water Level in STAAD.Offshore?

No, we cannot. As per the API code clause 1.3.8, the Marine Growth is the most near the Mean Water Level but can be significant 200 feet or below the Mean Sea Level. The STAAD.Offshore is designed to take the marine growth data at and below the Still Water Level.

3. When I generate the STAAD file with wave loads using the STAAD.Offshore module, the file throws up errors while opening in STAAD.Pro and the Wave Load Cases are messed up.

This is most likely due to the fact that you have specified the first wave load case number such that either that case number or the subsequent wave load case numbers match with primary or combination load case numbers in the original file. If this is the reason then you need to specify the wave load case number in such a way that there is no duplication.

4. I have specified the added mass coefficient and the drag coefficient as zero. However, STAAD is still generating Wave Loads in the Vertical direction.

The answer to your question as to why the wave loads are generated inspite of the drag and the added mass coefficients defined as zero is inherent in the Morison’s equation. If you look into the Morison’s equation, you will see the following:

Here,  C_m= Inertia coefficient = 1 + C_a

               C_a =Added Mass Coefficient

          C_d = Drag Coefficient

The first term on the right side of the equation is the inertial force and the second term is the drag force.

The inertia force is again the sum of Froude-Krylov Force and Hydrodynamic Mass Force. Expressing the Morison’s equation in these terms, we have the following:

The first term on the right hand side of the equation above is the Froude-Krylov Force and is not dependent on the added mass coefficient and the drag coefficient. So, even if you specify the added mass coefficient and the drag coefficient as zero, it is not necessary that the Force will be zero.

Also you have specified a 0 degree wave, the fluid particle acceleration is only in the vertical direction. Hence, we will have the force in the vertical direction of the structure.

5. When I try to open my staad.pro model in offshore, I receive the error: “Structure file has syntax errors. check the <filename>.err file for reasons”. What is the cause of this error ?

The error indicates that there is some problem in the command input in the .std that you are trying to open. A (filename).err file is created inside the same folder from where you are trying to open the .std file. This file can be opened using Wordpad or notepad and should indicate specifically where the software is failing to read the input.

6. I added a section to the STAAD.Pro section database and used it in my model. Now I am trying to open the STAAD.Pro model in STAAD.Offshore and I am getting error messages saying “structure file has syntax errors”. How do I get Offshore to recognize my defined sections ?

When you add a section to the STAAD.pro section database, it gets added to the mdb file corresponding to that country database. For example if you added a section to the American Section database, this data would be added to the AISCSections.mdb file. These mdb files can be found within the X:\SProV8i\STAAD\Sections folder where X represents the local drive in which STAAD.Pro is installed. You need select the appropriate mdb and copy it to the folder C:\Users\(user name)\AppData\Roaming\Bentley\OpenSTAADOEM\Sections from where Offshore reads the sections. There would be an existing file by the same name and that file needs to be replaced by the file you are trying to copy. You would then be able to open the file in STAAD.Offshore.

It is better to have STAAD.Pro and STAAD.Offshore closed when you do these external file transfers. Moreover it is always a good idea to keep a backup whenever you are trying to replace or modify any standard mdbs.

7. Is it possible to specify the heave + roll and heave –
roll in the same load case?

You cannot create heave + roll and heave – roll in the same load group. You need to create two different groups with the directional factor as + 1 for heave + roll case and -1 for heave – roll case.

In the STAAD file however, you can manually edit the load cases two specify all the load items in the same load case – however, doing that you run the risk of under estimating the inertial forces.

 8. What does the message “The section Type PIPE/TUBE/OPEN/PRISMATIC cannot be established for some members. These members have been shown in red. The property table contents of these members will also be shown in red.” means while opening the STAAD.Pro model in STAAD.Offshore and how does this affect?

If you are using a transportation module, the aforementioned message does not make a difference as only the lumped masses are used for calculation of inertial forces. But it does affect in case the Wave Loading module is used. The Wave loading is calculated using the shapes of the members. Currently the STAAD.Offshore program is able to account for the following sections only:

1- Pipe, 2- Rectangle hollow (including square hollow), 3- Wide flange or Channel, 4- Rectangular Solid and 5- Circular solid

If the STAAD.Pro model has sections other than the aforementioned ones, their shapes wil not be accounted for leading to an erroneous calculation of wave loads.

How is Mpl and Mstrip Calculated?

The design procedure for base plate design in RAM Connection is based on AISC Design Guide 1. The Design Guide includes some design examples that will clarify how these parameters are calculated.

The equations used to calculate the plate bending moment in the "Flexural Yielding (Bearing Interface)" check are discussed in Section 3.3.2 of the Design Guide.

The strip moment in the "Flexural Yielding (Tension Interface)" check is calculated assuming the tensile loads in the anchors generate one-way bending in the base plate about assumed bending lines. The location of the bending lines depends on whether the placement of the anchors. See Figure 3.1.1(b) and Figure 4.5.2 in the Design Guide. The program assumes a 45 degree load distribution from the anchor to the bending line to determine the width of the bending strip.

1. How does Staad "direct" a spring to determine if it is in compression or tension?
2. What is the difference between a LOAD COMBINATION and a REPEAT LOAD?
3. In a structure which has wall panels in addition to other things, is it possible to temporarily disable some of the outer panels and analyse just the rest of the structure consisting of interior beams, columns, and slabs?
4. What's the difference between ELASTIC MAT and PLATE MAT for spring support generation?
5. The output from my STAAD run contains the warning message :THIS STRUCTURE IS DISJOINTED
6. Warning message in output file: This structure is disjointed, accompanied by several instability warnings
7. I am using STAAD.Pro 2002. When the STAAD Analysis and Design engine is running, you can't minimize the box that shows the activities in progress - it is always on top. I like to start the "run analysis" then go on to work on something else while it is running. It is not very convenient having the box on top of everything. How can i fix that?
8. I need to specify a cable member. Can I give it the proper properties using user define tables?
9. My STAAD outout file contains the warning message : **WARNING** THE POISSON'S RATIO HAS NOT BEEN SPECIFIED FOR ONE OR MORE MEMBERS
10. Read/write Error in Unit No. 17
11. I need to analyze a frame whose members have been rotated about the local z axis. Is there anyway to model this situation using STAAD? Can you input a point and define the orientation of the local axis of that point? Or is there some other way to model this situation?
12. Is IX the St. Venant's Torsional Constant or is it the Polar Moment of Inertia?
13. How does one get a report indicating whether the applied loads are in equilibrium with the support reactions?
14. How can I check whether the story drift of the floors are within allowable limits?
15. I have a structure with supports marked as elastic foundation. I am getting an error message "Error 0550" when I run the analysis. What could be the cause of this?
16. I want to use the Master/slave command to model a rigid diaphragm in STAAD.Pro 2001. The problem is two columns separated by 40 ft. One column goes from joints 1 to 2 and the second column goes from joints 3 to 4. I wish to have a rigid link between joint 2 and joint 4. The program gives an error of multiple structures. What additional connections do I have to do to tie these joints together?
17. I am going to incorporate into my model, rock anchors which will be installed down the center of the pipe piles. In case you are not familiar with these, they are a thread rod attached to the top of the pile, go down the center and are anchored into the rock and are used to take the uplift forces in the pier. I was planning on using the post tensioning command. Is this correct?
18. When I try to analyse a model which contains the ELASTIC MAT command for generation of soil spring supports, I encounter an error message : Error 0550* support joints are collinear
19. Do you have any thumb rule/ formula for estimating the time required for solving a structure involving plates elements?
20. I have to analyse a structure for temperature load. The temperature difference is 600 deg C. (from 0 deg C to 600 deg C). Which value of alpha I shall use, (i.e. alpha for 0 deg or alpha for 600 deg) for the analysis? Can I use an alpha value for the mean temperature?
21. Can I carryout a machine foundation analysis using STAAD PRO (Embedded Block foundation and Pile foundation)?
22. UNEXPECTED COMMAND IN LOAD DATA CHECK SPELLING AND ORDER OF DATA IN CASE NO. 1
23. What is the procedure used by STAAD.Pro in computing the stiffness matrix of a tapered beam?
24. While using the "Master Slave" command to define a rigid diaphragm in a framed multi-storeyed structure, what criteria should one adopt to determine the "Master node"?
25. I am analyzing a simply supported beam, which is 20 feet long. There is a concentrated force acting at the mid-span point of the beam. In one case, I model it as a single member and apply the load at midspan using the member load option. In another case, I model it as 2 separate members, each 10 ft long, and apply the load at the central node using the JOINT LOAD option. The member cross section is a W12X26 from the American steel table. When I look at the deflection at the 10 ft point, using the PRINT SECTION DISPLACEMENT command for case (a) and the PRINT JOINT DISPLACEMENT command for case (b), the values do not match. Why?
26. Can I design a stringer using STAAD.Pro?
27. In the member end forces output, why are two values being reported for axial forces? Also, why is it that sometimes the numerical values of these two are the same and sometimes they are not?
28. When I try running the analysis on STAAD.pro 2001, I get the error message error message as "Fatal Error: Cannot start analysis Engine". However, when tried with another machine with Win 95/98. The same software is working fine without giving any error.
29. I have a continuous beam, and all members have the same E and same properties. I run it once with one set of member properties. I double the depth of the members and run it a second time. The results of the second run (midspan moment, reactions, etc.) do not match those from the first run. Shouldn't the results stay the same as the EI remains constant for both the beams?
30. During the analysis of a large model, the analysis engine stops with the error message Read/write ERROR in Unit No. 17
31. I want to ignore the stiffness of certain members during analysis but want the loads applied on them to be transferred to the structure. Can I use the INACTIVE MEMBER command for this ?
32. How to add/change/modify sections to the Section Database?
33. ERROR-STAAD BUILT IN MEMORY BLOCK HAS OVERFLOWED
34. When I save my file in STAAD.Pro, all REPEAT commands are changed by STAAD to the expanded format. The same thing happens when I do a File > Save As. I would like to retain my input using the REPEAT commands. Is there any way to do that ?
35. What is a Reference Load Case?
36. Can we specify time-history loads in a Reference Load Case?
37. Some of the STAAD.Pro icons are missing from the toolbar region. How can I get those back ?

1. How does Staad "direct" a spring to determine if it is in compression or tension?

For the purpose of defining the sense of the force in the SPRING TENSION/SPRING COMPRESSION facility, the following rules are adopted in STAAD :

A support reaction force is considered TENSILE if it is opposite to the positive direction of the axis under consideration. Another way of putting it is that, for this condition, the displacement along that axis of the support node is in the same direction as the positive direction of that axis.

A support reaction force is considered COMPRESSIVE if it is along the positive direction of the axis under consideration. Another way of putting it is that, for this condition, the displacement along that axis of the support node is in the direction opposite to the positive direction of that axis.

These rules are applicable for global axis supports, as well as inclined axis supports.

Hence, use the center of the circular pipe as the REFERENCE POINT for the INCLINED supports. The local X axis for the inclined supports will then point from the perimeter towards the center of the circle. The supports around the circumference can then be assigned COMPRESSION only springs. .

2. What is the difference between a LOAD COMBINATION and a REPEAT LOAD?

The difference lies in the way STAAD goes about calculating the results - joint displacements, member forces and support reactions. For a load combination case, STAAD simply ALGEBRAICALLY COMBINES THE RESULTS of the component cases after factoring them. In other words, for example, in order to obtain the results of load 10, it has no need to know what exactly constitutes load cases 3, 4 and 5. It just needs to know what the results of those cases are. Thus, the structure is NOT actually analysed for a combination load case. With a REPEAT LOAD case however, the procedure followed is that which occurs for any other primary load case. A load vector {P} is first created, and later, that load vector gets pre-multiplied by the inverted stiffness matrix.

3. In a structure which has wall panels in addition to other things, is it possible to temporarily disable some of the outer panels and analyse just the rest of the structure consisting of interior beams, columns, and slabs?

STAAD has an INACTIVE MEMBER command. This command can be used with beam/columns as well as plate elements. The members and elements subjected to this condition will have their stiffness, as well as any applied loading on them, ignored. This means, only the remainder of the structure will be treated as being active. So, what you can do is use the INACTIVE MEMBER command in conjunction with CHANGE to create a multiple analysis model.

In this manner, a single STAAD input file can represent various stages of construction of the structure. Take a look at example 4 in the Examples manual. Although that example illustrates the procedure using just beams, the same can be used with plates included in the structure.

4. What's the difference between ELASTIC MAT and PLATE MAT for spring support generation?

With the ELASTIC MAT you enter a list of joints from which STAAD will attempt to form a perimeter which encloses an overall area. This is done with a convex hull algorithm. Lastly, areas are assigned to each joint. If the convex hull rules are met, the algorithm works well. However for mats with irregular edges or holes, the algorithm may not do what the user expects and one may end up with springs with unreasonable spring constant values.

Since many mat foundation problems have plates defining the entire mat, we have added the PLATE MAT option where you enter a list of plates that entirely define the mat. Roughly 1/4th of the area of each plate is assigned to each joint in the plate in the same manner as uniform pressure or self weight is distributed.

So if you have the foundation support entirely defined by plates, then use the PLATE MAT option. Otherwise use the ELASTIC MAT option. With this option please observe the rules listed in the Tech Ref Manual. Avoid convex angles. You may have to subdivide the region into several sub-regions with several ELASTIC MAT commands. Add "PRINT" to the end of the command to see the areas assigned to each joint where a support is generated.

5. The output from my STAAD run contains the warning message :

THIS STRUCTURE IS DISJOINTED. IGNORE IF

MASTER/SLAVE OR IF UNCONNECTED JOINTS.

Is STAAD telling me that my structure is in several pieces?

This is referred to in STAAD as Multiple structures. The outline below explains the process for identifying the disparate components and merging them so they form a single structure. One of the consequences of having multiple structures, namely, structural instabilities, is also discussed. 

6. Warning message in output file: This structure is disjointed, accompanied by several instability warnings.

The error message, "this structure is disjointed..." is caused by multiple structures in the model. Multiple structures exist when one portion of the model does not have any way of transferring forces to another portion. It is possible to create a model that visually appears to be a single structure, but upon closer inspection it is revealed that the model contains two or more unconnected structures. Instability warnings may also appear in the output file, due to the fact that the structure appears to be properly supported when, in fact, it is not.

What do we mean by member connectivity? What determines whether two members are connected so that one can transfer loading to another? Consider two lines that intersect in 3D space, with the starting point of one line lying on the longitudinal axis of the other line. The fact that the end of one member lies on the axis of another is not sufficient to ensure connectivity. Connectivity is insured only when intersecting members are divided into segments that meet at a single, common node. ("Common node" means a single node number. Two separate node numbers, both having the same X,Y,Z coordinates is called a duplicate node situation. You can test for duplicate nodes in the model by pulling down the Tools menu and selecting the Check Duplicate command, then select the Nodes command from the Check Duplicate sub-menu).

7. I am using STAAD.Pro 2002. When the STAAD Analysis and Design engine is running, you can't minimize the box that shows the activities in progress - it is always on top. I like to start the "run analysis" then go on to work on something else while it is running. It is not very convenient having the box on top of everything. How can i fix that?

If you click on the top left corner of that box, you will find an option called "Do not Stay on Top". Switch that on. You can then make that window recede behind other windows.

8. I need to specify a cable member. Can I give it the proper properties using user define tables?

The only property that a cable requires is the cross section area. So any property type which can enable the program to obtain the area would be acceptable. A few examples are :

As a PRISmatic section with the diameter specified using the term YD :

MEMBER PROPERTY
1 PRIS YD 1.0

or

As a PRISmatic section with the Area specified using the term AX

MEMBER PROPERTY
1 PRIS AX 0.35

or

As a PIPE section with the outer and inner diameters specified using the terms OD & ID

MEMBER PROPERTY
1 TA ST PIPE OD 1.1 ID 0.0

If you wish to specify it as a user defined section using a user table, that would be acceptable too.

9. My STAAD outout file contains the warning message :

**WARNING** THE POISSON'S RATIO HAS NOT BEEN SPECIFIED FOR ONE OR MORE
MEMBERS/ELEMENTS/SOLIDS. THE DEFAULT VALUE HAS BEEN SET FOR THE SAME.

What does this message mean?

The Poisson's ratio is one of the fundamental material properties required to perform the analysis of a structure. It is generally used to obtain the value of G (Modulus of Rigidity) using the relationship

E=2G(1+Poisson)

where E is the Young's modulus

If you have failed to specify the Poisson's ratio, STAAD attempts to "guess" the value of that term based on the value defined for E. For example, if E is in the neighbourhood of 29000 ksi (steel), Poisson's will be chosen to be about 0.30. If E is in the neighbourhood of 3150 ksi (concrete), Poisson's will be chosen to be about 0.17.

If you would like to see what value has been chosen by the program, you may specify the command

PRINT MATERIAL PROPERTIES

after all the CONSTANTs have been provided. The Poisson's ratio will be reported in the output file along with some of the other CONSTANTs.

It is best to specify a value explicitly instead of having the program estimate a value on its own.

10. After I launch the analysis, the program completes some of the processes, and then comes up with the message :

*** STAADPro ERROR MESSAGE ***
** Read/write Error in Unit No. 17
++ Calculating Joint Displacements. 16:24:21

What does this error mean, and what can I do to avoid it?

This is very likely due to the fact that you have run out of disk space, particularly on the drive which is being used for the SET TEMP environment variable in NT and 2000 operating systems. Since this is usually the C: drive, you need to increase the free space available on the C drive, or whichever is being used for SET TEMP.

 11. I need to analyze a frame whose members have been rotated about the local z axis. Is there anyway to model this situation using STAAD? Can you input a point and define the orientation of the local axis of that point? Or is there some other way to model this situation?

We presume you mean that the member is rotated about the local "X" axis and not the local "Z" axis. When you use STAAD's default coordinate system, the local "X" is the longitudinal axis of the member, and local Z is generally the major axis of the member. So, changing the orientation of a member involves rotation about the local "X" axis, and not the local "Y" or local "Z" axes.

There are a couple of ways to change the orientation.

a) By specifying an angle using the BETA command. This is explained in Sections 1.5.2, 1.5.3 and 5.26.2 of the Technical Reference Manual. You may also refer to example 1 of the Examples manual for a sample problem which shows the usage of the command.

b) Using the REFERENCE POINT method. This too is explained in Sections 1.5.2, 1.5.3 and 5.26.2 of the Technical Reference Manual.

In the STAAD.Pro GUI, you may click the right mouse button, select Labels, and switch on Beam Orientation to get a visual representation of the directions the local X and Y axes point to.

Graphically, you can specify the BETA angle from 2 places :

If you go to the General - Property page on the left side of the screen, you will find the Properties dialog box on the right side and it contains a tab called Beta Angle through which the value can be specified.

If you go to the Commands menu on top of the screen, choose Geometric Constants - Beta Angle.

Graphically, you can specify the REFERENCE POINT by going to the Commands menu on top of the screen, and choosing Geometric Constants - Member Reference Point.

12. Is IX the St. Venant's Torsional Constant or is it the Polar Moment of Inertia?

IX is generally known just as the Torsion Constant. For a circular cross section, the torsion constant equals the Polar moment of inertia. For non-circular cross sections, it usually is less than the polar moment of inertia. If you have the AISC publication T114, you will see it referred to in that document using the expression J. If you have the textbook "Roark's Formulas for Stress & Strain, 6th edition, Warren C.Young, McGraw-Hill", you will find it being referred to using the expression K in section 9.2 of the book.

13. How does one get a report indicating whether the applied loads are in equilibrium with the support reactions?

There is an option which can be provided along with the PERFORM ANALYSIS command for getting this information. It is called PRINT STATICS CHECK. It is explained in Section 5.37 of the STAAD.Pro Technical Reference Manual. The sample below shows how this is done.

LOAD 3 LATERAL FORCES
JOINT LOAD
4 6 8 10 FX 12.5
LOAD COMBINATION 10
1 1.2 2 1.4 3 0.9
PERFORM ANALYSIS PRINT STATICS CHECK
PRINT ANALYSIS RESULTS
UNIT NEWTON MMS
START CONCRETE DESIGN
CODE BRITISH
FYLD 425 ALL
FC 35 ALL
DESIGN COLUMN 45 57
END CONCRETE DESIGN
FINISH

If you prefer to use the graphical method for specifying this option, this is how it can be done.

In the Modelling mode, click on the Commands menu from the top of the screen. Select Analysis | Perform Analysis. A Perform Analysis dialog box will be displayed. Set the radio button on Print Statics Check. Click on OK.

Save the file and run the analysis. Then view the output file. (This can be done from File | View | Output file | STAAD Output). If you scroll down to the region where the PERFORM ANALYSIS command is specified, the equilibroum report will be available after that command.

14. How can I check whether the story drift of the floors are within allowable limits?

If you have STAAD.Pro 2001 Build 1005 or Build 1006, you can specify a command called

PRINT STORY DRIFT

in your input file. Run the analysis. Then check your output file, The drift for each story will be reported. You will have to manually verify that this is within your allowable limits.

15. I have a structure with supports marked as elastic foundation. I am getting an error message "Error 0550" when I run the analysis. What could be the cause of this?

There are a few reasons why you will run into this error :

1) The ELASTIC MAT command is meant for generating support spring constants for the support nodes of plate elements. The feature does not work in the case where the support spring generation is requested at nodes which aren't connected to any plate.

STAAD attempts to find the tributary area of each node for which the elastic mat command is specified. It determines this area on the basis of the "influence area" of the nodes. If those nodes are attached to a non-plate entity such as a beam, the corresponding nodes do not have an "influence area".

2) The plates might be inclined to the global horizontal plane (XZ). Presently, the feature works satisfactorily only if the plate is truly horizontal. An inclined plate or a vertical plate cannot presently be handled by this feature.

16. I want to use the Master/slave command to model a rigid diaphragm in STAAD.Pro 2001. The problem is two columns separated by 40 ft. One column goes from joints 1 to 2 and the second column goes from joints 3 to 4. I wish to have a rigid link between joint 2 and joint 4. The program gives an error of multiple structures. What additional connections do I have to do to tie these joints together?

You would need to split the columns into 2 members each.

There is a limitation that a master joint cannot have supported directions or be connected to a member or element that is connected to a support; similarly, the slave joints may not have supported directions or be connected to a member or element that connects to a support.

17. I am going to incorporate into my model, rock anchors which will be installed down the center of the pipe piles. In case you are not familiar with these, they are a thread rod attached to the top of the pile, go down the center and are anchored into the rock and are used to take the uplift forces in the pier. I was planning on using the post tensioning command. Is this correct?

If the prestressing force is applied after the piles are driven into the soil and the pile cap is cast, the load type you may want to apply in analysing the model is the one involving the MEMBER PRESTRESS command. That is because, there is a small anomaly in STAAD in the definition of the terms PRESTRESS and POSTSTRESS. The way STAAD defines these terms and the way they are conventionally defined are opposite to each other. You will find an explanation of this anomaly in Section 1.16.5 of the STAAD.Pro Technical reference manual under items 4 and 5.

If you want an example which demonstrates the usage of these commands, please refer to example problem 6 in the STAAD.Pro Examples manual.

18. When I try to analyse a model which contains the ELASTIC MAT command for generation of soil spring supports, I encounter an error message :

Error 0550* support joints are collinear.

If you look under the "Notes" item of Section 5.27.3 of the STAAD.Pro
Technical Reference Manual, you will find that the program attempts to put
together a closed surface from the joint-list that accompanies each ELASTIC
MAT command. When you specify the commands in the following manner :

SUPPORTS
1 ELASTIC MAT DIRECT Y SUBGRADE 259
2 ELASTIC MAT DIRECT Y SUBGRADE 259
3 ELASTIC MAT DIRECT Y SUBGRADE 259
4 ELASTIC MAT DIRECT Y SUBGRADE 259
5 ELASTIC MAT DIRECT Y SUBGRADE 259
6 ELASTIC MAT DIRECT Y SUBGRADE 259
7 ELASTIC MAT DIRECT Y SUBGRADE 259
8 ELASTIC MAT DIRECT Y SUBGRADE 259
9 ELASTIC MAT DIRECT Y SUBGRADE 259

it fails to find a closed surface, because a single joint does not form a
closed surface.

Based on the type of model you have, you can replace those multiple ELASTIC
MAT commands with a single command as follows :

SUPPORTS
1 TO 625 ELASTIC MAT DIRECT Y SUBGRADE 259

19. Do you have any thumb rule/ formula for estimating the time required for solving a structure involving plates elements?

Run times depend on many factors. For static analysis without master/slave, the run time for large problems is dominated by the triangular factorization time.

Triangular Factor. Time = '[ (Fac) * (6 * no. of joints / 1000) * (bandwidth /100)**2 ] / 3600 in hours.

The bandwidth is printed with problem statistics.
Fac is a computer dependent factor.
Use Fac = 0.20 if you have 1.5GHz with 1 GB memory and 9600 SCSI drives.
Use Fac = 0.70 if you have 1.0GHz with 256 MB memory and 7200 drives.
Use Fac = 1.50 if you have 0.5GHz with 128 MB memory and 5400 drives.

As an example:

500Mhz, high bandwidth
Triangular Factor. Time = '[ (1.50) * (6 * 23000 / 1000) * (9000 /100)**2 ] / 3600 = 466 hours = 19.4 days

1000MHz Faster computer, more supports, lower bandwidth:
Triangular Factor. Time = '[ (0.70) * (6 * 22000 / 1000) * (5000 /100)**2 ] / 3600 = 64.1 hours = 2.67 days

20. I have to analyse a structure for temperature load. The temperature difference is 600 deg C. (from 0 deg C to 600 deg C). Which value of alpha I shall use, (i.e. alpha for 0 deg or alpha for 600 deg) for the analysis? Can I use an alpha value for the mean temperature?

The following answer was supplied by Ray:

Since STAAD is linear for material behavior, an alpha that results in the desired strain and displacement would be best. You can enter any positive value for alpha. The units of the alpha value must be the same as the temperature change units since STAAD does not explicitly enter temperature units.

21. Can I carryout a machine foundation analysis using STAAD PRO (Embedded Block foundation and Pile foundation)?

The answer is Yes. The piles have to be modelled as columns. If the machinery sits on a slab, that will be modelled using plate elements. The supports for the model are going to be the resistance (based on subgrade modulus) offered by the soil, which may be modelled as springs. The dynamic loads due to the machinery will be modelled as forcing function loading, either as discrete time-force pairs as shown in example 16, or as a sinusoidal loading as shown in example 22.

22. Attached is a portion of my STAAD output file which contains an error messsage as shown :

30. LOAD 1 (1.4DL + 1.7LL)
31. SELF Y -1.4
32. MEMB LOAD
33. 11 TO 16 UNI Y -2.8
34. 11 TO 16 UNI Y -5.1
35. START CONCRETE DESIGN

**WARNING - UNEXPECTED COMMAND IN LOAD DATA
CHECK SPELLING AND ORDER OF DATA IN CASE NO. 1
COMMAND= START CONCRETE DESIGN
CHECK RESULTS CAREFULLY, LOADS MAY HAVE BEEN LOST
***STAAD.Pro WARNING***
ANALYSIS NOT PERFORMED - SO ABOVE COMMAND CAN NOT BE PROCESSED.
*********** END OF THE STAAD.Pro RUN ***********

Can you explain what it means?

You are following up your load instructions with a concrete design statement. (Notice that after 11 TO 16 UNI Y -5.1, you are specifying START CONCRETE DESIGN). There is no instruction for performing the analysis. A concrete design cannot be done until after the analysis has been performed. So, you need to specify the command PERFORM ANALYSIS in between those 2 lines, as in,

11 TO 16 UNI Y -5.1

PERFORM ANALYSIS PRINT STATICS CHECK

START CONCRETE DESIGN

23. What is the procedure used by STAAD.Pro in computing the stiffness matrix of a tapered beam?

1. Define the static deflection curves of a beam due to unit displacement at each of its 12 degrees of freedom while maintaining the displacements at the remaining 11 degrees of freedom as 0. These curves are usually referred to as shape functions.

2. Using the principle of virtual work, calculate each term of the stiffness matrix. This is an integral involving E (modulus of elasticity), I (moment of inertia for the applicable axis), and the product of the second derivative of the two shape functions which are relevant to the specific stiffness matrix term being generated. The integration is performed over the full length of the member.

Simpson's method is used in performing the integration. STAAD uses 100 integration points over the member length. The moment of inertia is calculated at the start and end of each integration point.

24. While using the "Master Slave" command to define a rigid diaphragm in a framed multi-storeyed structure, what criteria should one adopt to determine the "Master node"?

For an ordinary static analysis, any of the joints in a master/slave system can be the master joint.

A second point to understand about the Staad.Pro 2001 input is that the command

SLAVE ZX MASTER j JOINT joint-spec

should be used for ordinary floor rigid diaphragms (assuming they are parallel to the ZX axes). This command sets the ZX plane to behave rigidly for inplane actions; while out-of-plane shear and bending will behave flexibly.

The command

SLAVE RIGID MASTER j JOINT joint-spec

should be used if the master/slave connections behave rigidly in all directions and rotations.

For a natural frequency calculation and dynamic analysis, the master joint should be the joint nearest to the c.g. of the masses associated with the master/slave joints.

If the c.g. is well off the structure as in an L shaped structure with narrow wings, you may want to add a joint at the c.g. just for the purpose of being the master; [remember to connect that joint to another joint with a dummy (low E value) member if it is not already connected].

25. I am analyzing a simply supported beam, which is 20 feet long. There is a concentrated force acting at the mid-span point of the beam. In one case, I model it as a single member and apply the load at midspan using the member load option. In another case, I model it as 2 separate members, each 10 ft long, and apply the load at the central node using the JOINT LOAD option. The member cross section is a W12X26 from the American steel table. When I look at the deflection at the 10 ft point, using the PRINT SECTION DISPLACEMENT command for case (a) and the PRINT JOINT DISPLACEMENT command for case (b), the values do not match. Why?

The difference is due to shear deformation.

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 the shear areas are part of the user specified member property input.

As a result, the joint displacements consist of the pure bending component plus the shear deformation component.

When you ask for intermediate section displacements along a member span, STAAD calculates these using the moment area method from

* the joint translation and rotation (which includes the shear deformation component as explained above)

* flexural deformation of the member (the shear deformation component is not considered here)

In other words, in the implementation of the moment area method, only the term (a) contains shear deformation where as term (b) does not. This is an error in the program, albeit a small one.

If shear deformation is eliminated from all of the above calculations, this discrepancy will be removed. Shear deformation is part of the above calculations only when the shear areas AY and AZ are non-zero values. When member properties are specified using methods such as defining sections from the built-in steel tables, or by specifying them as PRISMATIC sections with a DEPTH and WIDTH value, STAAD internally calculates the shear area before proceeding with the stiffness matrix assembly.

The user may nullify the effect of shear deformation by doing one of the following :

* Provide the properties using the PRISMATIC attribute, and specify just AX, IX, IY and IZ, as in,

1 PRI AX 21 IX 35.4 IY 45.3 IZ 85.75

In this case, since AY and AZ are not specified, shear deformation will not be calculated.

* Provide a very large value for the shear areas AY and AZ, thereby minimizing the shear deformation, as in

1 PRI AX 21 IX 35.4 IY 45.3 IZ 85.75 AY 1E10 AZ 1E10

In this case, the large shear area will result in negligible shear deformation.

26. Can I design a stringer using STAAD.Pro?

To answer your question, we would like to offer some insight into how the capabilities of a structural engineering software are related to the type of sections you wish to analyze and design.

Typically, almost all structural engineering programs have 2 parts to them :

* Analysis - Computing forces and moments in beams, columns, plates, etc., nodal displacements, support reactions.

* Design - Checking the adequacy of a section for a beam or column to carry the forces induced into that member from the applied loads on the structure.

For analysis, these programs do not care about the shape of the cross section. Regardless of what the shape is, the programs simply look for 4
pieces of information : Area, Moments of Inertia about the 2 principal axes, Torsional Constant. If shear deformation calculation is desired, the shear areas should be provided too. However, to help you avoid the chore of specifying these 4-6 values, these programs also allow you to specify the section as one of the standard shapes built into the program, and then internally calculate these 4 quantities using the property calculation rules for that shape. So, if the shape you wish to have analyzed is one such standard shape, you can simply define it in that way, as for example, the flange width, flange thickness, web depth and web thickness for an I shape.

However, if the shape of your section does not conform to one of the built-in shapes that the program supports, you will have to type in these
4-6 property values using a property type usually called PRISMATIC.

For design however, shape does matter. That is because, all design codes are written to allow design of only certain specific shapes, due to the fact that buckling of elements of the cross section plays a major role in determining the capacity of the section. Usually, these shapes are limited to I shapes, T shapes, Channels, Angles, Double angles, Z shapes, Rectangular tube shapes, Circular pipe shapes, etc.

So, the answer to your question is :

Analysis - Yes.

Design - Depends on the shape of the section, and the code according to which it should be designed.

27. In the member end forces output, why are two values being reported for axial forces? Also, why is it that sometimes the numerical values of these two are the same and sometimes they are not?

There are two values because member end force output consists of the forces and moments at the start node as well as at the end node of the member.

At the start node, a positive value of the axial force indicates axial compression, and a negative value indicates axial tension. At the end node, a positive value indicates axial tension, and a negative value indicates axial compression.

Generally, if the values at the start and at the end are not the same in magnitude, it is due to a load acting along the local X axis of the member. A typical example of this is a column (vertical member) subjected to selfweight loading. The difference in magnitude of the axial forces at start and end should be equal to the load acting along the local X axis of the member.

28. When I try running an analysis in STAAD.Pro, I get an error message "Fatal Error: Cannot start analysis Engine" .

The error may be caused by the fact that the paging file size which has been set in Windows in your machine is not large enough to run the program.

1. You can determine whether this is true by doing the following. Make sure you are logged in with Administrative privileges before you attempt any of the following steps.

Using Windows Explorer, locate the file "SProStaad.exe" which should be present in the folder "\Sprov8i\staad\sprostaad".

Run that file by double clicking on it. If it comes up with a message that the paging file size is not large enough, that is an indication of the problem mentioned in step 1 above.

2. If the above is true, you can remedy the error by doing the following:

In Windows, go to Control Panel - System - Advanced Settings

Select performance options. The total paging file size for all drives will be listed in a window. You may want to increase it.

Exit those settings dialog boxes, and try running the program again. Chances are it should work this time.

If that does not resolve the issue, please uninstall STAAD.Pro and reinstall the software.

29. I have a continuous beam, and all members have the same E and same properties. I run it once with one set of member properties. I double the depth of the members and run it a second time. The results of the second run (midspan moment, reactions, etc.) do not match those from the first run. Shouldn't the results stay the same as the EI remains constant for both the beams?

The difference is due to shear deformation. Instead of specifying properties as YD and ZD (which would trigger a shear deformation calculation), provide the values as

AX, IX, IY and IZ

and check the results. They should stay the same.

Or, if you are running STAAD.pro 2004 or later, specify the command

SET SHEAR

on the second line of your input file. This will forcibly switch off shear deformations from the calculations.

Now, changing just YD or ZD should have no effect on the results.

30. During the analysis of a large model, the analysis engine stops with the error message

*** STAAD.Pro ERROR MESSAGE ***
** Read/write ERROR in Unit No. 17

*** ERRORS IN SOLVER ***

Even though the hard disk may have plenty of free space, the problem might be caused by the fact that the disk is formatted with the FAT32 format. This format has a file size limit of 4.2GB. So although there is enough disk space, the single file size limit is exceeded for the STAAD solved matrix file (.L17).

You can determine the type of formatting in effect for your drive by going through the following simple steps.

• On your Windows Desktop, go to My Computer.
• Select the drive which serves as the repository for your SET TEMP settings on your machine. If there is only one hard drive on the machine, it will be that drive. 
• Right click on the drive and select  Properties
• Make sure the file system is NTFS
• Make sure there is enough Free space

If the above also indicates FAT32, you need to find a computer that has its disk formatted with the NTFS format (which does not have a file size limit). Most new Windows XP based computers have the NTFS format.

31. I want to ignore the stiffness of certain members during analysis but want the loads applied on them to be transferred to the structure. Can I use the INACTIVE MEMBER command for this ?

Loads defined on inactive members are not considered in analysis. If you are trying to ignore the stiffness of the members, you may consider defining a dummy material for these members with low E value so that the stiffness contribution from these members become negligible. That way loads applied on these members are still going to get transferred to the rest of the structure.

32. How to change /modify the Section Database?

Or

How to add new sections to the Section Database?

 Please download the  video file from the following link  which demonstrates this feature :

 http://communities.bentley.com/products/structural/structural_analysis___design/m/structural_analysis_and_design_gallery/258994.aspx

 An arbitrary section ISMB 200 has been added to the Indian Section Data Base.

33. When users run the analysis, it gives an error message... "ERROR-STAAD BUILT IN MEMORY BLOCK HAS OVERFLOWED".

If you are trying to analyse a large model, you may need to increase the memory alloted to STAAD.

From the Edit menu, choose Edit Input Command File and go to the STAAD.Pro input editor. Please add
the following statement as the first line in your model, on the line before the command STAAD SPACE—

MEMORY 85

STAAD SPACE

Run the analysis. This input will allow up to 85,000,000 4-byte words for STAAD's internal memory
block (default is 80 million).

If you still get the error message, increase the memory block till the error message is eliminated.

34. When I save my file in STAAD.Pro, all REPEAT commands are changed by STAAD to the expanded format. The same thing happens when I do a File > Save As. I would like to retain my input using the REPEAT commands. Is there any way to do that ?

The REPEAT and REPEAT ALL commands were used at times when the graphic user interface was not
so advanced and the primary mode of data input used to be by typing commands in the input file. But these days, the graphic user interface in Staadpro is so developed that there is no need for the users to go to input file and type in information. Consequently the commands like REPEAT and REPEAT ALL lost importance and have now been replaced by GUI features like Translational Repeat , Circular Repeat etc.

However they are still recognized as valid commands by the engine so that if your file contains those commands, Staad would be able to read the geometry information. When the file is saved using the GUI, the REPEAT commands get replaced. This improves the performance of the software because it no longer has to remember blocks of information that used to appear within the REPEAT commands.

However if you want to retain the REPEAT commands in the input file, keep a copy of the full set of commands like
JOINT COORDINATES, MEMBER INCIDENCES and  ELEMENT INCIDENCES which predominantly use the REPEAT options,  and place them after the FINISH command at the end of the input file. When you are done with
the full job and would not be saving the model using the GUI any more, you can finally replace the JOINT COORDINATES, MEMBER INCIDENCES, ELEMENT INCIDENCES sections with the copied blocks containing the REPEAT commands placed at the end of the file . Then run the analysis again and you will have your analysis results and at the same time your input file will contain the REPEAT commands. 

When you do a File > Save As, the file is saved by the GUI and hence the REPEAT commands are again replaced. If
you would like to save the file by a different name and retain the REPEAT commands, the best thing to do is to do the Save from outside the STAAD environment. You may use Windows Explorer. You can simply copy the original .std file and then rename it using Explorer to get your second file.

35. What is a Reference Load Case?

Reference Load is an array of load data. It is not a primary load case and STAAD will not analyse the Reference Load Case. The Reference Load Case forms an input in the primary load case.

The advantage of using the reference load case in models having non-linear analysis like a P-Delta or Member Tension/Compression is that it can be used to specify load combinations in a primary load case and thereby make the program analyse the combinations directly without analysing the individual component cases specified as Reference Load Cases. This can result in saving of time and computer resources significantly.

36.Can we specify time-history loads in a  Reference Load Case?

No, we cannot. We can only specify static load items like nodal loads, member loads, floor loads, surface loads, temperature loads etc directly in a reference load case. Loads like Wind Load, Seismic Load, Time History Load, Moving Load etc., which needs the program to generate the load items, cannot be specified within a Reference Load Case.

37. Some of the STAAD.Pro icons are missing from the toolbar region. How can I get those back ?

These icons can be turned on/off from the top menu by going to View > Toolbars and checking the appropriate check box. This should fix the problem. In case it does not, you may reset the toolbar settings back to the default by carrying out the following steps

Close STAAD.Pro
Go to Start menu -> Click Run-> Type REGEDIT , Click Ok.
The Registry Editor window will appear
Please click HKEY_CURRENT_USER ->Software->Research Engineers-> STAADPro-> select 2007 ( or the version number that you may have ) and delete it.
Close the registry editor window and re-open STAAD.Pro.

See Also

Product TechNotes and FAQs

Structural Product TechNotes And FAQs

External Links

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

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