Bridge Building Competition - 2015

The Rules

• The bridge is to be built from spaghetti and hot glue.
• You will only be allowed to use the amount of spaghetti and glue that you can “buy” with the “money” you earned playing Cargo Bridge. 
• The bridge shall be free-standing and must span two level surfaces which are 16 inches apart. • The support for the bridge shall be from the top of the level surfaces. The edges of the level surfaces cannot be used in any way for support.
• The bridge must include a decking of spaghetti to provide a suitable road surface at least 2 inches wide across the full span of the bridge so that a Hot Wheels car may pass over it. Gaps in the bridge deck should be small enough that the car can roll over the bridge. The car must be able to move along the length of the decking unobstructed from end to end.
• To test the bridge string will be looped around the center of the bridge. All loads will be suspended from this string. There must be a clear space directly below it to allow loads to be attached. Loads will be attached to the string until the bridge breaks.
• The winner of the contest will be the bridge with the highest Load capacity to bridge mass ratio, also known as performance ratio. (Found by dividing the load that the bridge supported by the mass of the bridge.)

The Bridges

Bridge #1

Mass of bridge: 5.33 oz

Money spent: $2850

Load: 28.5 oz
 Load capacity to bridge mass ratio - 5.347

Bridge #2

Mass of bridge:4.55 oz

Money spent: $4150

Load: 8.5 oz
 Load capacity to bridge mass ratio - 1.868

Bridge #3

Mass of bridge: 3.77 oz

Money spent: $2400

Load: 18.5 oz
 Load capacity to bridge mass ratio - 4.907

Bridge #4

Mass of bridge: 12.35 oz

Money spent: $4300

Load: 43.5 oz
 Load capacity to bridge mass ratio - 3.522

Bridge #5

Mass of bridge: 12.59 oz

Money spent: $3250

Load: 139.5 oz
 Load capacity to bridge mass ratio - 11.080

 

Bridge #6

Mass of bridge: 4.52 oz

Money spent: $2200

Load: 18.5 oz
 Load capacity to bridge mass ratio - 4.092

 

Bridge #7

Mass of bridge: 6.10 oz

Money spent: $2800

Load: 251.5
 Load capacity to bridge mass ratio - 41.229

Bridge #8

Mass of bridge: 7.51 oz

Money spent: $4400

Load: 13.5 oz
 Load capacity to bridge mass ratio - 1.797

Bridge #9

Mass of bridge: 6.10 oz

Money spent: $6100

Load: 119.5 oz
 Load capacity to bridge mass ratio - 19.590

Bridge #10

Mass of bridge: 2.75 oz

Money spent: $1350

Load: 8.5 oz
 Load capacity to bridge mass ratio - 3.090

Bridge #11

Mass of bridge: 6.49 oz

Money spent: $2600

Load: 68.5 oz
 Load capacity to bridge mass ratio -10.554

Bridge #12

Mass of bridge: 4.73 oz

Money spent: $2300

Load: 48.5 oz
 Load capacity to bridge mass ratio - 10.253

Bridge #13

Mass of bridge: 4.44 oz

Money spent: $1400

Load: 18.5 oz
 Load capacity to bridge mass ratio - 4.166

Bridge #14

Mass of bridge: 4.66 oz

Money spent: $2000

Load: 13.5 oz
 Load capacity to bridge mass ratio - 2.896

Bridge #15

Mass of bridge: 6.00 oz

Money spent: $3450

Load: 43.5 oz
 Load capacity to bridge mass ratio - 7.25

 

Bridge #16

Mass of bridge: 2.54 oz

Money spent: $2950

Load: 28.5 oz
 Load capacity to bridge mass ratio - 11.220

Bridge #17

Mass of bridge: 5.01 oz

Money spent: $2850

Load: 144.5 oz
 Load capacity to bridge mass ratio - 28.842

Bridge #18

Mass of bridge: 10.23

Money spent: $5800

Load: 64.5 oz
 Load capacity to bridge mass ratio - 6.304

Bridge #19

Mass of bridge: 7.76

Money spent: $4650

Load: 114.5 oz
 Load capacity to bridge mass ratio - 14.755

Bridge #20

Mass of bridge: 11.32

Money spent: $5150

Load: 119.5 oz
 Load capacity to bridge mass ratio - 10.556