Over Monday and Tuesday of this week, I have learned a lot about truss bridges. They are not an entirely new topic to me because in December of 2019 I did a project on finding the area of a trapezoid for math class. Part of it was to find a practical use for the concept we were teaching about. Many truss bridges are trapezoidal, so naturally, I came across them during my search for trapezoids in daily life. Despite this, I learned so much more this week. Particularly, I learned about the structural strength of shapes, different types of trusses, and

To start, I learned about the structural strength of shapes. A key piece of knowledge that I got out of the class was that while other shapes may be deformed, triangles can not be unless the sides themselves break. This is because a triangle’s angles are fixed, unlike those of other shapes. We can’t just build pyramids though, so in order to prevent all other shapes collapsing when used in structures, engineers use bracing. This is done by making triangles!

I also learned about different types of trusses. While truss bridges can take many different shapes, one thing that they all have in common is that any square shapes found in them are divided into different triangles using bracing. It amazed me that there are so many different types of truss bridges.

Finally, I learned about thermodynamics, and how bridges can warp if they’re firmly attached on both sides. This is because when materials heat and cool they expand and contract. To prevent this from causing a bridge to buckle or distort, engineers use different methods to allow for expansion. These include using different expansion joints.

All in all, today’s lesson was quite interesting, and I learned a lot. I’m excited to do this week’s project!