It broke with a series of pops and cracks, flinging bits and pieces into a crowd gathered nearby, but Corey Dyke didn’t care.
The Monmouth Academy junior pumped fists and yelled out a loud, “Yeah!” when his spaghetti bridge caved under more than 8,435 pounds of pressure.
Twenty bridges made of spaghetti built by Monmouth students gave way to thousands of pounds of pressure Tuesday in a Spaghetti Bridge Breaking Competition, held in the Richard and Jean Higgins Materials Testing Laboratory inside Boardman Hall at the University of Maine in Orono.
Longtime Monmouth math teacher Jeff Gosselin started the competition more than 10 years ago with the goal of providing an engineering lesson for the high school students, who attempt to build the strongest bridge possible.
“The students learn some engineering skills,” Gosselin said. “They learn there are certain [specifications] and attributes that the bridge has to meet, they learn patience and how to overcome obstacles, particularly if the glue doesn’t dry the way it’s supposed to, and they learn about deadlines for getting things in on time.”
In the early years of the competition, he said, most bridges, which must be at least 3 inches high and must span at least 5 inches, weren’t holding more than 250 pounds. Now, several bridges per year can take more than 2,000 pounds.
Gosselin said the winning bridge’s 8,435 pounds on Tuesday was probably in the top four all-time. A few years ago one bridge held up to more than 25,000 pounds of pressure.
Dyke didn’t imagine his bridge, which he built with classmate Jared Jacobs, would hold up so well.
“I was hoping for 2,100 pounds just to get a good grade and that was it,” Dyke said. “That was the goal. But going up this high, that was nice. [The weight] started to go higher and higher and I got more excited as it climbed up.”
The competition field is made up of geometry students, who are mostly in the sophomore class, and algebra II students, who are mostly juniors. There are 40 to 45 bridges entered every year.
Students must follow several strict rules in building their bridges, with stricter rules for the second-year bridge-builders.
The construction material is Delverde brand perciatelli, a long, thick, hollow spaghetti-shaped pasta that is especially strong when dry, making it the perfect pasta for a small bridge. Students are allowed one box, or a pound, with which to build. The entire bridge cannot weigh more than a pound.
Students used Elmer’s glue to bond the parts. Only three pieces of pasta can be glued together in one bond, although several groups of three pieces can be used in the supports.
The competition begins every year with a preliminary round at Monmouth Academy, during which the pasta bridges must stand up to at least 300 pounds for the geometry students and 400 pounds for the algebra II students. If a bridge misses at least one specification, extra weight is added to the minimum.
The bridges that held up to weights at Monmouth Academy moved on to the University of Maine in Orono, which Gosselin said is the closest place with sufficient testing capabilities. At the university on Tuesday, the geometry students went first, while the algebra students went on a tour of the Advanced Engineered Wood Composites Center. After the geometry students were finished, the algebra students did their testing.
For testing, bridges were placed one by one on one of two load frames, also known as universal testing machines. A wood board was placed on top of the bridge to make sure the weight would come down in a level manner. Then with the press of a button, an actuator lowered from the load frame and applied pressure to the wood board with the bridge underneath.
Some bridges exploded quickly with pieces of pasta shooting out and hitting the observers, many of whom wore protective glasses. Other bridges failed slowly, with spaghetti stalks shearing off the sides and the supports crumbling.
The bridges that broke slowly didn’t necessarily hold the most weight, but in the real world those bridges would be the most successful, said Eric Landis, a UM engineering professor.
“If you’re a bridge inspector, you can go to that bridge and say, ‘Oh, there’s some spaghetti missing but the bridge is still standing,’” he said. “That’s what we like. It’s called redundancy in structures, and it’s a very valuable trait.”
Dyke said last year that his bridge didn’t even make it out of the first round.
“We had a mishap with weights sliding off one side, and [the bridge] broke,” he said. “Last year I used different types of triple bonds and I don’t think the legs were as tightly packed. This year we used more horizontal [pieces] and different triples. I think there was twice as much spaghetti as I used last year.”
The sophomore team of Julia DeStefano and Mackenzie Kelley won its class competition with 4,397 pounds of pressure.
Gosselin, who is retiring this month after 24 years at Monmouth Academy, is hoping the school’s math department continues the competition.
“I think [the students] realize they have accomplished something pretty neat,” he said. “This is not an easy project, and I think they feel a real pride in even seeing their project destroyed.”