Exercise 3.1: Bridge Designer

You are a community planner and engineer. The mayor of your community has come to you with a proposal for a building project. There is a large river (> 20 m wide) that runs through the centre of your community. The bridge that currently spans the river is more than 100 years old and needs to be replaced. This bridge has 2 driving lanes and a special protected sidewalk for bicycles and pedestrians. You should come up with a new design that will allow the same amount of traffic to cross it.

Your task is to come up with a design that will be safe, durable, and ecologically responsible. You will make a presentation to the city council and several experts and show them why your bridge design is the best for the community.

Answer the following questions.

1. What type of bridge do you want to build: beam, arch, suspension, truss, etc.? Why is this the design the best?

2. What material should the bridge be made out of? Why? Consider the properties of materials that you studied in this lesson.

3. The mayor of your community is concerned about the cost of building this bridge. What would you say to convince the mayor that your bridge is cost efficient?

4. The president of the local fishing club is concerned that building this bridge will affect the population of fish in the river. What would you say to convince the president of the fishing club that your bridge will not negatively affect the fish?