Concrete canoe team boats best-ever finish in national competition
By accepted definition, concrete as most know it is solid, hard, heavy. But toss some civil engineering students' concrete concoction--a-canoe--into the lake and the result boggles the mind.
With their special concrete mix, plus some engineering ingenuity, UW-Madison civil engineering students boated their best-ever finish--seventh of 26 teams--at the National Concrete Canoe Competition, held June 24 through 27 in Golden, Colorado.
The competition challenges students' skill both on land and in the water. Categories in which the students are judged include an 11-page technical paper, an oral presentation, the finished canoe and a trade-show-style display. The UW-Madison team took first place with its creative, out-on-a-limb TV shopping network-style oral presentation.
Students also participate in men's and women's two-person 200-meter sprints, a four-person co-ed sprint, and men's and women's two-person distance races, which include a 100-meter slalom course and a 500-meter distance race. Clemson University, the competition's overall winner, finished in first place in all racing events, while the Madison team consistently placed in the top 10.
UW-Madison's canoe, Prominence, this year won its spring regional competition and is the team's fifth boat in as many years to earn an invitation to the national competition. Team members debuted King Kong Crete in 1996, and followed with Wisconcrete Woody in 1997, Phibrous Phantom in 1998 and Great Dane in 1999.
The 21-foot, 125-pound Prominence capitalizes on the Great Dane's best qualities and incorporates new ideas, including a deeper V-shaped hull for better paddling control, and a lighter concrete mix.
Regular concrete, a mixture of cement, an aggregate such as sand or gravel, and water, weighs 140 pounds per cubic foot. According to contest rules, the mix must be at least 75 percent Portland cement, and can include strengthening agents such as fly ash, microsilica and polypropylene fibers. The UW-Madison team designed and tested 10 mixes to create its final product: a mix that weighed 38 pounds per cubic foot-24.4 pounds per cubic foot lighter than water. "Already most of the best mixes, if you just capped a big cube of them, will float, because they are inherently lighter than water," says team co-leader Dave Golden. "So it's not the displacement that makes the concrete float-it's actually that it is lighter than water."
A more organized production schedule gave his team a significant advantage as well, says Golden. The group poured its canoe in early November, rather than February, as in years past. At the same time, students also poured a prototype "practice" canoe that enabled the paddlers to become comfortable with the boat's design, yet keep the final product fresh for competition.
This year, 21 team members made the trip to Colorado, although rules limit the official roster of participants to just 10 people. The remainder of the group listened to presentations, learned from their peers' displays, and helped set up the UW-Madison display, a miniature movie theater. "We usually take everybody who's been active in this year's project, plus a couple of people who weren't necessarily as active this year, but who show interest and potential for next year, because the competition really gets them fired up," says Golden.
Although the group didn't make its goal to place in the top five, Golden says, "We're already getting excited for next year." The group has begun to identify aspects to improve-including finding a way to give its paddlers more practice, despite Madison's frigid pre-season weather and frozen lakes.
Master Builders, Inc., and the American Society of Civil Engineers sponsor the annual competition. Other participants include Oklahoma State, Florida Institute of Technology, Michigan State University, University of Washington, University of Alabama-Huntsville, University of Florida, Universite Laval (Canada), Western Kentucky University, South Dakota School of Mines & Technology, California Polytechnic University, Drexel University, Rowan University, University of Minnesota, University of California-Davis, North Carolina University, Cornell University, University of New Orleans, Virginia Tech, U.S. Air Force Academy, University of Idaho, Kansas State University, University of Rhode Island, University of Texas-El Paso, and the University of Texas-San Antonio.