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Rock 'N' Row
The ONU steel bridge team assembles their bridge at the ASCE
North Central Regional Conference on Satuday, March 31, 2012.
Leave it to engineers to seek out the ultimate challenge. Like creating a competition where the goal is to be the best at building something out of the worst possible material.
That is essentially what a team of Ohio Northern University engineering students did this weekend (March 30-April 1) when they raced a 300-pound concrete canoe at the American Society of Civil Engineers’ North Central Regional Conference. The three-day conference, which was hosted by ONU, brought together hundreds of students from across Michigan and Ohio for concrete canoe and steel bridge building competitions.
The ONU concrete canoe team placed second overall, with second-place finishes in all races and the presentation, and third place finishes in the technical paper and product/display categories. Unfortunately, in their first year of competition, the ONU steel bridge team was disqualified for exceeding the time limit. Still, participating in the event was memorable and provided the team with valuable experience.
"Hosting the conference was awesome. Although it could be stressful at times, it was an incredible experience, and an absolute honor being able to showcase the University and the College of Engineering to the region. It turned out to be the perfect weekend, too — beautiful weather, and some of the best competition for the Concrete Canoe and Steel Bridge events that I've seen in my four years attending this conference," said Lee Suanders, a senior civil engineering major from North Olmstead, Ohio.
About the concrete canoe
“The first thing we get asked is, ‘How does it float?’ says Lindsay Ziegler, a senior civil engineering major from Bowling Green, Ohio. “We have to explain that it’s not the same concrete you see in the sidewalk. It’s not made of the same stuff.”
The key is understanding the difference between concrete and cement. Concrete comprises two parts — cement, which is a powder that hardens when mixed with water, and aggregate, which is the material that cement bonds together to provide strength. Traditional concrete mix, such as that used in a sidewalk, uses sand and gravel as aggregates along with Portland cement. The ONU Concrete Canoe team uses the same cement, but very different aggregates.
“First of all, our aggregates are very, very small. If you were to look at the canoe close up, you would see that they look like tiny white specs,” says Ziegler. “Secondly, they are a lot lighter. One of the aggregates we use is called glass bubbles. They are practically lighter than air.”
But the concrete, or mix, is just part of what makes the canoe float. Design and shape also play an important role. These variables add to the complexity of the competition and require the expertise of more than just civil engineers. Fortunately for ONU, the T. J. Smull College of Engineering has a variety of majors to help out.
“Our entire team is made up of engineering majors, but we aren’t all civil engineers. We have some mechanicals and even some computer engineers. You don’t have to be civil to have fun on this project,” says Ziegler.
The competition itself consists of four separately scored areas: a research and design report, an oral presentation of the design, display and aesthetics, and races. The teams compete in men’s and women’s endurance races, men’s and women’s sprints, and coed sprints.
The ONU team worked for months to prepare for the competition. They spent weeks testing concrete mixes to develop the perfect formula to give their canoe strength and buoyancy while remaining as light as possible. The canoe was cast in December and left to cure over winter break. When the team returned to campus, its members put their signature on the canoe, compressing the concrete by cutting stainless steel cables that were cast into the canoe while under 300 pounds of tension. This engineering concept, called a pre-stress system, makes the canoe incredibly strong — nearly as strong as the bonds forged between the team members.
“There is something great about being part of a team. You send the entire year working on this. It’s like a senior capstone, but for freshmen, sophomores, juniors and seniors. It’s immeasurable how much you can get out of this event. We love it so much,” says Ziegler.