Now
that your group has chosen one of your three different
designs that you created during the engineering step, it's time to begin constructing your bridge.
You will need the following materials for your bridge construction project:
- a piece of cardboard or wood at least 90 centimeters long by 50 centimeters
wide to serve as the base for your bridge;
- Popsicle sticks;
- white glue;
- thread for use with a suspension bridge (only if needed); and
- a metric ruler for measurements.
As a review, the bridge design that you actually model must:
- span (cross) a distance of 30 centimeters;- the deck of the bridge must be at least 5 centimeters above the surface being crossed;
- the deck must allow a golf ball to be rolled from end of the bridge to the other without falling off to simulate the bridge being used by the local users of your bridge; and
- be easy to assemble.
Mark the obstruction that your bridge will span on the cardboard or wood by drawing a 30 centimeter-wide area placed 30 centimeters from each end of the cardboard, which puts it in the middle. In order to allow your bridge to be tested to destruction you need to cut an 8 centimeter-square hole in the middle of this area. This diagram should help you.
You may now begin to construct your bridge. You may not place any supporting material for your bridge inside the obstruction area. Don't forget that your bridge must be at least 5 centimeters above the obstruction area as well.
You will probably want to test your bridge early to make sure that your bridge deck will allow the golf ball to roll across your bridge. Talk to your teacher or parent to borrow the golf ball.
As you create your bridge you will need to keep track of how many Popsicle sticks you use so that you will be able to enter this information into the database when asked.
Once your bridge model is complete and the glue is dry you should move onto the next section of the website to find out how to test it.