Understanding Structural Engineering Building Bridges Understanding Structural Engineering

Bridges are very important structures in our transportation system Bridges are very important structures in our transportation system. They allow us to carry loads across such obstacles as rivers, canyons, and roads. Bridges must be designed to withstand large amounts of weight while maintaining safety and stability. Why do we need bridges?

Beam Bridges Consists of a horizontal beam supported by end piers Can’t span a great distance because the further apart the piers, the weaker the bridge Beam Bridges

Truss Bridges Consists of an assembly of triangles Made from straight, steel bars Bars rarely bend Can span a further distance than beam bridges Truss Bridges

Arch Bridges Most are made of steel or concrete Very strong bridge design Can span up to 800 feet Arch Bridges

Suspension Bridges Can span a great distance (2,000-7,000 feet) Most have truss system underneath to keep from bending of twisting Massive steel cables in an “A” shape help support the bridge Suspension Bridges

Thinking like an Engineer! Not only do structural engineers have to design bridges that with withstand extremely large amounts of weight, they also must keep in mind: Earthquakes Strong Winds Freezing and Thawing Type of land Purpose of the bridge Cost of the bridge Thinking like an Engineer!

Now that you have become an expert on bridges, it is time for you to build and test your own bridge!