West Point Bridge Designer 2007 http://bridgecontest.usma.edu/download.htm Students: Use the above link to download your own copy of West Point Bridge Designer 2007 to your computer at home. It is free. There are other versions, but you MUST use the 2007 version. Once you have downloaded and installed your own copy to your computer, go to Start> All Programs> West Point Bridge Designer 2007>WPBD2007.exe to open the software and bring up the Welcome screen below. Make sure the radio button for ‘Create a New Bridge Design’ is selected and click OK. This next screen explains the Design Requirements and the software briefly. Please read the information and click Next.

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The next screen you encounter (above) is only for the USA competition. Just click Next. This screen (above) is very important. On this screen you will start setting your design limitations so that when you can create your bridges they follow the Design Brief. Make sure Deck Elevation is set to 8 metres; Support Configuration is set to Standard Abutments, No Pier and No Cable Anchorages. With this done, click Next.

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On the next screen you will be asked to select the deck material and truck loading. Make sure these are set to Medium Strength Concrete and Standard 180kN Truck respectively. Click Next. You are now up to designing your own bridge. On this screen you can decide to use a template provided, such as a Howe Through Truss or start with a clean sheet (except for lower joints along the deck). Selecting ‘<none>’ does this. A Warren Through Truss is selected in the screen shot above. When you have made your decisions click Finish.

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This screen will allow you to keep track of the bridges you design. Type your name in the ‘Designed By:’ box as Mr M has done and a code in Product ID to identify each version of bridge. In the example above Mr M is up to his 15th bridge design in 2008. This last screen explains what to do to bring up the drawing board. Read the instructions and click Finish.

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This screen is where you draw your design. You will notice that the joints along the deck are already placed. They are 4 metres apart. This is the minimum distance you are allowed between joints is 4 metres. The minimum overall height of the bridge is 7 metres. As you will be working at a scale of 1:100, the equates to the minimum distance between the joints on your model of 40 mm and a minimum height of 70mm. This little box appears on your drawing board. Working from left to right the tools available are: Joint Placement Tool: Use this tool to position the joints onto your drawing. Member Placement Tool: Use this tool to place members between joints Selection Tool: Use this tool to select components and modify them. Eraser: Use this tool to remove an unwanted joint or member. Above is a simple of example of placing joints and members to create a finished bridge.

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To see if your bridge works, click the light blue button with the truck in it (shown above). An animation of a truck driving over your bridge is displayed. Note the deep red members above. This means that the member is in maximum compression. The blue members that are blue are in tension, but as they are light in colour, they have not reached maximum load and can therefore be made thinner or from a less expensive material. If your bridge fails the test, this is what you will see!

Click the blue ‘truck’ button to test your design

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To get back to the drawing board, click of the button to the left of the light blue truck button. Once you have designed your bridge, you can also view the table shown below. This table shows the material each member is made from, its cross section type and size, length and the forces/loads acting in each member.

Once you are happy with your bridge design you can now print it out. This will give you a line drawing and a copy of the table of information about each truss member except for the loads and forces. An example of a print out is shown below. As this is only a line drawing you will need to use your own drawing skills to redraw your bridge with each member 5mm thick.

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Bridges You Could Create

Below are a number of different bridge types that you could modify to become the bridge you have designed. Some would make great designs in West Point Bridge Designer and some would be great made from Balsawood. Some may be great in both and some may be totally inappropriate. Look through the examples to help you decide what type of bridge you will design. You may like to make notes in the margin to help you make your decision.