A beautiful creek runs through a park in a big city. The city is planning to build a highway that will cross the creek. The highway bridge will need to support heavy car and truck traffic.The creek is shallow and does not have boat traffic, although the local residents fish in it. The people who live near the creek are afraid that the bridge will be ugly and negatively impact the scenic beauty of the area. What should the city do?

A railroad is being built over a small rural river.There is limited boat traffic under the bridge.The trains are very heavy, and the existing wooden covered bridge will not be able to hold the weight of the trains. What should the county do?

These forces push on ends of members in a truss.

A truss bridge currently spans a deep river in a large city. There is heavy boat traffic under the bridge. Automobile traffic backs up on the bridge whenever it opens for boats to pass through. Traffic is especially heavy during rush hour, and commuters are angry about the constant delays. This is also an important site in the city, and the citizens want this bridge to be a symbol for them. What should the city do?

These forces pull on members in the trusses

What are the two ends of a bridge (the bank) that support its weight?

A local park is interested in building a bridge over a short ravine. They have stressed that keeping costs low is very important to them. What type of bridge would you recommend they build?