Using Tedds (US design example)
In this exercise you will design a steel beam in order to learn how to use any of the calculations in the extensive Tedds Engineering Library.
Allow about 15 minutes to complete this exercise.
Design information required for this exercise
We wish to check the following RHS steel beam:
Design Information | ||
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Design Code | AISC 360 | |
Dimensions | Length | 16 ft |
Effective length factor | 0.80 | |
Design Forces | Moment | 90 kips ft |
Shear | 15 kips | |
Axial compression | 10 kips | |
Proposed section | Shape | Rectangular HSS preferred |
Steel grade | A500 Gr C50 |
Running Tedds and locating calculations
You need to find an appropriate calculation, run it and enter the design information. You will see just how easy this is.
Entering data in the automated calculation user interface
The General Automated Calculation Interface Explained | |
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An '(i)' symbol to the left of a variable description shows that there is more information available about this particular variable. The information area (at the top of the dialog) displays any information about the selected variable (if available). You can also see this information by hovering the cursor over the '(i)' symbol. |
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Notes - display details about the calculations being performed. |
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Variables - lists all the current variables. Values can be selected from here to enter into the current interface. |
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Feedback - this allows you to send feedback to the development team. |
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Support - tells you how to obtain support in your region. |
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Data fields - enter information in these fields . Where appropriate, variables may have validation which prevents invalid information being entered. |
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Buttons... - allow you to enter more information or select a particular item. |
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Next/Back/Cancel/Finish - continue to the next page / return to a previous page /stop the calculations at the current point / return the data to your calculation document. |
Data Lists
You are now looking at a Data List: a tool that allows you to choose a section and see its properties at the click of a button.
Data Lists Explained | |
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Choose the shape from the left hand pane. |
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Choose the size from the right hand pane. |
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Details - click to see properties of the chosen selection. |
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Select - click to select the chosen selection. |
In this case, both a HSS 10x6x3/8 and a HSS 12x8x1/4 may prove adequate but which is the lighter?
Automated calculations and library items
You have probably realized by now that this calculation caters for all kinds of steel sections, dimensions and loading. For each possibility and check, there is an item in the Library - in fact this calculation has over 150 items. When you use a calculation like this, Tedds automatically chooses the appropriate items for your options and input, and puts them together to make up the complete design.
The progress log
The progress log helps to keep you informed about a calculations progress during lengthy calculations, it is also used by some calculations to report the status of specific checks or other pertinent information. When writing your own custom calculations you can add information to the log or you can modify the default options to provide more detailed information about what your calculations is doing which can be helpful for resolving errors.
This particular calculation does not use the progress log to report any additional information.
Examining finished calculations
OK, but how is your chosen section performing? The main interface displayed the design forces, capacities and utilizations but you may want to examine the results in more detail.
Re-calculating
Changes are a fact of life for engineers, they always have been, and they always will be! You need to be able to take account of any changes and update your calculations quickly. With Tedds this is no problem.
Hidden text
All the calculations performed by Tedds are available in the output and in general so they are – but at times some intermediate calculations are hidden to reduce the amount of output. It is simple to view these and to include them in your printout.
The header & printing
To finish this example let’s look at a few points about saving and outputting your results.
Saving and output options
You can save every Tedds calculation to a unique file that you can recall and edit any time in the future. The file extension .ted is unique to Tedds.
- Click to display the file menu.
- Save your file and give it a name - it’s a good idea to save all the examples you will produce in the course of completing the guide, for future reference.
- The output you see in the document can be printed direct to a printer, but you have other options.
- Click the drop-down button adjacent to Send To on the file menu to view these.
- Choose the option of sending the output to Word and experiment with the other options if you wish. Once your output is in a Word document, you can edit it as much as you wish.
- By clicking the drop-down button adjacent to Save As on the file menu you can also save the active document, or all documents in the active project to PDF.
Performing a new calculation
How do you start a new calculation in Tedds?
The Select Calculation dialog will open, from where you can select and start a new calculation in a new document.
Managing multiple related calculations
Can several calculations be saved in a single document?
As stated earlier, each calculation must be saved to a unique file - however multiple files can be collected together in a single project. They can then be organized as required using the Project Manager.
Benefits of projects include:
- you can specify a shared document header for all the project files,
- locating files is made easier - when you open the project all files within it are opened automatically,
- calculations can be placed into named groups, making them easier to manage.
To start a new project:
What next?
Congratulations! You have completed the first exercise and now know all you really need to make use of the wide range of calculations available in the Tedds Engineering Library and to begin using Tedds productively. Take a look through the index and try some more. How about:
- carrying out a wind load calculation?
- designing a retaining wall?
- designing an RC footing?
- analyzing and designing a timber rafter, beam or post…
The choice is yours, and all these calculations work in the same straightforward, intuitive way. Some calculations may also include Data tables which are designed to look like tables from printed references, so that you immediately feel at home with them. Indeed we hope you will find yourself recognizing them.
What can you do if the Library does not contain the exact calculation for which you are looking? You need to perform a number of calculations, and could do with a calculation to help you out with these. First of all, TELL US:
- if you are running a calculation, then you will see a Feedback button to the left-hand-side of the interface,
- if you are not running a calculation, then you can choose the Feedback… option from the Help menu.
We are constantly working to expand our Engineering Library and your input helps us do this!
But you don’t have to wait until we produce these for you – you can write them yourself. We will look at this in the next exercise: Writing Tedds Calculations - Stage 1