Period H Bridge Competition - The Results are In!

Winning girder bridge during the competition. 

Last Thursday, period H conducted their bridge competition and the results are now in! We focused on the two facets of bridge construction. First, we were looking to hold a lot of weight by balancing forces on the bridge. We examined how certain bridges control those forces using tension and compression. The students implemented designs using trusses, girders, and cables to control the unbalanced forces that may affect the performance of a bridge.

Figure 1. Bridge Building Costs in dollars.

Second, we looked at the cost of bridge building. We assumed that the materials to build the bridge costs money. Each team recorded the amount of money spent on straws, card stock, and fishing line. A bridge can be cost ineffective when too many materials are used during construction. In period H, we looked at the ratio of dollars spent to the force applied to the bridge before they broke. 

Figure 2. Bridge comparisons on costs and force applied due to mass and gravity.

 The winning bridge had a ratio of $199,100 : 7154N or $2,783 per newton. This is exhibited in Figure 2 where it had a relatively low cost compared to the amount of weight it held. The winning bridge had a girder design, but the class had several successful models

Period H bridges before the competition.

Period H self-anchored suspension bridge design with underlying arch design.

Update:

Homework:

Due: Part 2 - Pittsburgh Bridges Scavenger Hunt add to your project packet


Period H:  Bridge packet due by Thursday.
Periods A, B, D, and F: Bridge packets are due on Friday after the competition.

Science PSSA April  5th & 6th