1. Kyle Concannon & Ty Clinger
Bridge Summary
Kyle Concannon & Ty Clinger

2. Broke
The center of the arch compressed which held the bridge, but since it twisted in the middle, and broke the strut on the left. We could’ve put a lateral brace under the arches.

3. Stresses
Our bridge had Compression, Torsion, and Tension. The we balanced our bridge was by cutting a divot on the bottom ends so they would compress against the wall. Our bridge had a lot of torsion, we could tell because the block on the top was facing towards the front. As we added weight we could see that our bridge was having tension on the middle.

4. Changes
We changed our design as soon as we started. We wanted to build the bridge 4 pieces thick and 2 pieces wide but we realized that we wouldn’t have enough balsa wood left, so we changed it from 4x2 to 3x2. We added gussets where the wood came together on the arches. We added gussets in between the two arches, and connected them with a brace. Also we added two 45 degree braces.

5. Witness
Yes, they did have similar breaking points. Ours broke at the end near the testing blocks.
Ryan's and Colton's bridge broke in the similar place like ours, but theirs was a flat bridge while ours was an arch.

6. Efficiency
We ended up having the highest efficiency in our class. I believe that the structure we had that helped us get he highest efficiency was how tall the arch was, the lateral bracing so that the arches would stay close together, and the divots on the end because as the bridge compressed the walls would help support the bridge. I think the thing that helped us the most was the divots because as the bridge compressed the divots on the end pushed against the walls.

7. Tips Build an arch bridge Don’t doubt your bridge!
Gussets are your friend.