Design Rationale

Project Design:

We brainstormed and researched on many designs to find out how to make a bridge that is light yet able to hold a lot of weight. We came up with all sorts of truss bridges. We decided on one with a truss bridge under and arch such that there is support from both top and bottom. When we thought we have found the right design, we decided to scrap it as we found out something.

Throughout our research, we found out that we do not have to make a bridge that can support load throughout its base since the testing of the bridge is only conducted at one point of the bridge. This allowed to us to come up with a different kind of bridge, where it is made up of 3 equal-length sections with 2 supporting points joined from the testing point to the other 2 sections, thus equally distributing the load in the middle of the structure to the other 2 sections.

With this, we wanted our base to be stronger. There is too much and unsupported area on the 2 end sections of the bridge. If we do not find a solution for this, the base might end up bending while supporting the load. We have come up many ways to solve this problem, like adding another supporting point from the end of the 2 supporting points to 2/3 down the exposed area of the base to support it. However due to the law of physics, this would only interrupt the equal distribution of the 2 supporting points. Thus, we've come up with the solution of joining the exposed area to the slopes, forming a triangle at the ends.

Our initial plan to making the bridge was to layer it 17 times (8 supporting inside, 9 outside) But we figured this would decrease the efficiency if we are going to hold all the weights they have but having a heavy bridge. Thus, we decided to decrease it to 11 layers instead.

With the planning of structure and guessing of the efficiency outcome to find out the layering amount of the bridge, we finally managed to come up with a bridge that is not only light but also able to hold much more than just a load of weight.

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