The building tryout is a hands-on event, and is very similar to the Bridge Building event. You will be required to design and build a bridge before the tryout day that meets the following specifications. If you do not have these materials available at home, you will need to go and buy them.
Task:
Construct a bridge out of popsicle sticks (thin popsicle sticks are suggested) that can hold the most weight. There is no minimum or maximum weight limit. The total bridge span must be longer than 25 centimeters, and the width of the bridge must be longer than 5 centimeters. There is no height limit. There must be room in the center of the bridge to accommodate a 5 cm x 5 cm x 2 cm wooden block and room for a chain to hang down below it. This space can be at any height, but it MUST be in the center of the bridge span. You will also be asked about the design and methods you used to build the bridge. If you made blueprints, bring them in.
Materials:
The Competition:
*Goggles MUST be worn by all people involved at all times during testing
On tryout day, your bridge will be tested. It will be placed on a testing surface with a 20 x 20 cm hole cut into it, and a 5 x 5 x 2 cm block with a chain attached will be placed on your bridge. A bucket will be attached to the bottom of the chain. You will have to load this bucket with sand while one other person holds it steady with yardsticks. Once the loading begins, you are not allowed to touch or make any adjustments to the bridge. The bucket may only be touched by the yardsticks. The bridge will be tested until it fails, or until the available sand runs out. Once the bucket touches the ground, loading must stop. The bucket will be weighed, and the score will be calculated.
Scoring:
Each bridge will be weighed before it is tested. The score is calculated by dividing the amount of grams held by the bridge by the mass of the bridge. This is the bridge’s structural efficiency. The maximum weight that will be counted is up to 10 kilograms. If your bridge holds more, it will be scored as if you held the max weight, which is 10 kilograms.
Example 1:
Mass of bridge: 10 g
Mass held by bridge:10 kg (10,000 g)
Score: 10,000g / 10g = 1,000
Example 2:
Mass of bridge: 20 g
Mass held by bridge: 15 kg (15,000g)
*the bridge held over 10 kg, but the score will be calculated with 10 kg
Score: 10,000g / 20g = 500
Example 3:
Mass of bridge: 5 g
Mass held by bridge: 6 kg (8,000g)
Score: 6,000g / 5g = 1,200
Random Tips from the Master Builder: