When we started, we wanted to put the block in the middle so that all of the weight doesn't fall on one side. Since it is in the middle, we had to find a way that the weight evenly distributes rough out the bridge. Our solution was to put triangles that force the tension and compression into even amounts. At the beginning, we planned to use 84 sticks that were used to make the bases and the triangles. We ended up using 100 just for that part, and 200 total in order to reinforce the bridge and to hold the sides together
The triangles that distribute the tension and compression
The sticks going across that connect the two sides I the bridge together
How it ended
Our bridge held the most in the class at 116 pounds. However, the top wasn't glued enough, so it popped off which caused the bridge to break. The 116 pounds was used as motivation because we welt that we could to better and pass 150 pounds. We expected it to hold more, but we worked even harder during the next time to make the bridge hold a lot. Take a look at our video and watch the bridge break.
Our second plaN
Our bridge broke at the top. This way our goal was to reinforce, reinforce, and reinforce. We loved our first brudge since it held the most in the class, but we wanted to build more. Since we held a lot of weight, we wanted to base it off of the same design. As you already know, triangles distribute the compression and tension evenly. This time however, the sticks that we used for reinforcements, were on the top and bottom. One of our struggles was abiding by the 50 perecent rule. Although we attempted to make accurate measurements, it was hard, so we took minor pieces of popsicle sticks and stick them in so we can glue on the triangles. We also had a struggle of gluing on the top since it was uneven. We had to rip off everything on the top, and rebuild it. This caused us to test two days later then when we could have been able to. Our bridge held 161 pounds which was tied for first in our class.
Notice the black line on the stick, that is a leftover stick that we used to make sure that the bottom was made evenly.
The sticks going up and down in between the triangle also help distribute the weight
How it ended
Our bridge broke by the top collapsing in. A lot of the sticks broke which meant that the sticks were holding the weight, and not the glue. Most of the parts of the bridge were scattered and broken, so we couldn't put it back together. All of the group contributed hard work and we are really proud of our work and what we have learned and accomplished throughout this project. All in all, everyone is excited from the results of our bridge, and we are confident on how bridges work and hold more weight.