How to Draw a Bridge in RISA

Step-by-Step Guide

1. 1

   Step 1: Click the RISA icon.

   The dialogue box functions to help the user to get started, however it overlooks the most important aspect of the design:
   Drawing the Grid.
   
   So we will begin by closing the dialogue box and drawing the grid. ,, 5@3 means 5 columns that are 3 feet (0.9 m) wide 3@1 means 3 rows that are 1 foot (0.3 m) deep/long , This allows you to retrieve the same grid later on.
   
   It's especially useful if you always use the same grid. ,,, This leads to a dialogue box appearing.
   
   It is pictured in the following step. , TopChords BotChords Webbing Columns Lateral Bracing ,,,,,,,,,,, DO NOT CLICK "Esc" TWICE! If you happen to do so, go to the Troubleshooting Section (Part 6) to get it figured out. ,, The image demonstrates the bottom chord. ,,,,,,,,,,,,,,,, This tells RISA that the bridge is attached to the ground here and will not be able to move or rotate in any direction. ,,,,
2. 2

   Step 2: When you open RISA you will encounter the following screen with the “Starting a Model” dialogue box as demonstrated in the picture.

3. 3

   Step 3: Close the dialogue by clicking "Close".

4. 4

   Step 4: Click on the icon pictured in the black box or Go to Modify --> Grid.

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   Step 5: Enter (5@3

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   Step 6: 3@1) into the “Define Drawing Grid” dialogue box as shown in Figure 3.

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   Step 7: Save Grid by clicking “Save” under the “Save and Recall Grid Settings”.

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   Step 8: Label the grid

9. 9

   Step 9: “Drawing Grid 2” when this dialogue box appears.

10. 10

    Step 10: Click “Ok”.

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    Step 11: Go to Spreadsheets --> Sections or simultaneously press the keys Ctrl+Alt+S.

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    Step 12: Label the sections by typing the following section names into the "Label" column.

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    Step 13: Begin Drawing the Top Chord.

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    Step 14: Click on the icon pictured in the black box or Go to Insert --> Members...

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    Step 15: Choose TOPCHORDS to be the Member Section Set as pictured.

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    Step 16: Set Release Codes to be “Pinned at Both Ends (Torsion Fixed)”.

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    Step 17: Click “Ok” to advance.

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    Step 18: Draw the first member from N1 to N2 as pictured Note that the nodes N1 and N2 will not show up until you click on them.

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    Step 19: Draw the second member from N2 to N3 as pictured.

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    Step 20: Draw the third member from N3 to N4 as pictured.

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    Step 21: Draw the fourth member from N4 to N5 as pictured.

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    Step 22: Draw the the fifth member from N5 to N6 as pictured.

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    Step 23: Click "Esc" on your keyboard to continue.

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    Step 24: Begin Drawing the Bottom Chord.

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    Step 25: Repeat Steps 1-10 to draw the bottom chord

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    Step 26: except in step 2 use BOTCHORDS instead of TOPCHORDS.

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    Step 27: Begin Drawing the Columns.

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    Step 28: Repeat Steps 1-4 to begin drawing the Columns

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    Step 29: except in Step 2 use COLUMNS instead of TOPCHORDS.

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    Step 30: Draw a member from N1 to N13.

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    Step 31: Draw a member from N6 to N14.

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    Step 32: Begin Drawing the Webbing.

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    Step 33: Repeat Steps 1-4 to begin drawing the Webbing

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    Step 34: except in Step 2 use WEBBING instead of TOPCHORDS.

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    Step 35: Draw a member from N1 to N8.

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    Step 36: Draw a member from N8 to N3.

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    Step 37: Draw a member from N3 to N10.

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    Step 38: Draw a member from N10 to N5.

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    Step 39: Draw a member from N5 to N12.

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    Step 40: Click on the icon pictured here or go to Modify --> Boundaries.

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    Step 41: This dialogue box will appear.

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    Step 42: Click the “Fixed” button in the following window.

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    Step 43: Click "Apply" to continue.

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    Step 44: Click on the nodes N13 and N14 to fix the bottom of the columns.

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    Step 45: It should look like this.

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    Step 46: Click Esc on your keyboard to continue.

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    Step 47: This is the picture of your screen when you accidentally press "Esc" twice.

48. 48

    Step 48: Go to Window --> Single View to return to your model.

Detailed Guide

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