West Point Bridge Design Software Exercise

The Project:

For this project, we used the software Bridge Designer, the 2016 version and the goal of the project was design a bridge and make it as cheap as possible, which meant creating as much tension and compression as possible, without the bridge breaking, and also so a truck in a simulation would be able to get across the bridge. The red in simulation meant compression, tension was blue. We could also add joints and bars to our bridge to create any type of bridge we wanted, such as a truss or suspension bridge. We could also change the bars to different materials and make them hollow if we wanted. I liked that the software had templates, so I could see the different price ranges for different types of bridges, and I also like how it would let me see where the specific areas of tension and compression were, so I could know where I had room to adjust my bridge to make it cheaper, but also where the main points of tension and compression are typically on a bridge. What I did not like about the software, was that often when I tried to create a bridge from scratch they would not let me run the test, but instead told me I couldn't run it because it was unstable, but I would rather learn from my mistakes in the simulation to see what I could have done better. My tips for designing the bridge would be try out a lot of different types of bridges and materials and thickness of pieces in order to try to get the price down. Also, don't just change one piece because that can cause the bridge to cost more because delivery for just one piece of material.

My Bridges:

I began creating my designs by using the truss bridge that looked like two truss bridges put together. I began testing each individual piece to see how thin I could get it before it would turn too red or too blue and would break. This helped me drive the price down by around 50,000 dollars and helped me a lot get a starting process and an understanding of the program. I then tried some different designs. I then tried a design that was similar to my first template, but it was just a single truss bridge. This dropped a lot off of the price because it was half of the size of the first design. I also made sure every piece in my design was carbon steel because that was the cheapest material I could use. I used the same technique I used when making my first bridge, which was decreasing each piece by a little to make them as thin as they could get before breaking due to compression or tension, and I did this until every piece of my bridge was either dark red or blue. I also made all of the piece of my bridge hollow because it made it a lot cheaper, but I did have to increase the thickness of a few pieces to make it a little stronger than it was now that it had hollow pieces. This bridge got into the high $180,000s, but it still could be cheaper. I tried using a suspension bridge and a double truss bridge that was on the bottom, not the top like my first design, but they were too high to make cheaper, and they would collapse under tension or compression as soon as something was adjusted. In total, I probably tried five different designs until reaching my final design. My final bridge design was similar to an arch bridge, but underneath the bridge. This design ended up being my final design because a few of the pieces on the bridge took the majority of the compression and tension, so I couldn't alter those a lot, but the other pieces I could make a lot thinner because the compression and tension did not effect it a lot. I made sure every piece would go as thin as it could before breaking. I also made all the pieces hollow and out of carbon steel to make it as cheap as possible, which ended up being around $181,000. If I could have improved my design at all or had more time to complete the project, I would have probably tried mixing materials on the bridge or mixing hollow pieces and not hollow pieces so I could make certain pieces even smaller, but other pieces would just stay the same thickness because they would be stronger, and this would probably bring down the price of my bridge a little, but other than that potential idea, I believe I did a good job testing various bridges and the tension and compression levels of their pieces in order to create a cheaper bridge.

Practice Bridges:

Final Bridge: