Joining the Concrete Canoe team as a freshman was one of the best decisions I’ve made this year. What sounded like a ridiculous and amusing club ended up inspiring me and teaching me a lot. It all started for me with a stop at Concrete Canoe’s table at the Student Activities Fair the first week of school. I began by adding my name and email address to the list, and then I asked if there was an application to join. I was told jokingly that I had to write a five-page essay on why I want to join, and at that moment I knew I’d made a good decision.

    I never realized how important having upperclassmen as mentors would be in college. Being a part of this club has given me the chance to interact with older students when I wouldn’t usually have the opportunity. Even though I was just a freshman who didn’t know anything, the upperclassmen were always eager to explain things to me or give me a simple task so that I could contribute to the team in some way with my limited skills and knowledge. They’ve also been very helpful with valuable advice since they were in my position not too long ago. The students I’ve met through canoe have also become inspiring role models for me. I see how passionate they are about designing, building, and competing for our team. They’ve put in hours and hours of work into the project, doing their best to ensure success for our team. I hope one day the other freshmen and I will be able to fill the big shoes they will leave behind when they graduate.

To be compliant with the rules of the competition, our concrete along with reinforcing must be lighter than water. That means that even when our concrete canoe is submerged fully (or “swamped”) during the swamp test, it will still float! This ensures the canoe will not sink to the bottom of the lake or river and prevents judges from having to fish out broken pieces of concrete canoes during the race portion of the competition.

Our mix design team this year was made up of fifteen members led by Kim Tsai and Connor Lee. They tested the best way to create lightweight cementitious composites in a student-led class called CEE428 during the fall quarter. They spent about 4 hours on it every week in class, and even more time outside of class.

To learn more about this year’s mix design (that passed the swamp test with ease), I got to ask one of our mix design leads and co-captain, Kim, about her work:

What does the concrete mix consist of?
    Kim: “Concrete is generally made with cement, aggregate (rocks), water, and admixtures. Admixtures are chemicals that change how the concrete works, generally by making it more workable.”

Could you briefly explain the process of how to make concrete float?

    Kim: “Our concrete floats because we add an admixture to make it airy, and we don’t use rocks or gravel aggregate that is used in typical concrete. Instead, we use an expanded glass bead that is very light. With the high air content and lightweight aggregate, our concrete turns out to be around 51 pounds per cubic foot—compared to the density of water at 62.4 pounds per cubic foot.”

How do you test if the mix is less dense than water?

    Kim: “We test our concrete density by measuring the volume of our samples and weighing them. Density = weight/volume! Our final test is to just put the sample in a bucket of water.”

  How did you end up choosing a mix to use for the canoe?  

    Kim: “We made about 32 different concrete mixes this year. Generally, the stronger the concrete is, the heavier it is. We had set a minimum strength and maximum weight that we wanted for our canoe, so from there, we picked a concrete mix that fit those goals.”

What is new about the concrete this year?

    Kim: “We added PVA Microfibers to the mix, which helped improve our strength compared to last year’s mix. The microfibers help hold tensile stresses induced in the concrete.”

What was the most challenging part of mix design?

    Kim: “The most challenging part of this year was to be organized and know enough to lead 15 other students when testing out the concrete. Everyone was busy with so many things, so it was important to be consistent each week in order to make progress.”

As you may know, the UW Concrete Canoe Team won the Race Points Category at the PNW Regional Competition. The race component of the competition is made up of five races: men’s endurance and sprints, women’s endurance and sprints, and a co-ed race. After a long, exciting, and eventful day in the sun, our team ended up with four first place finishes, one second place finish, and a few lost voices from cheering on the paddlers from the banks of the river.

The victory at Regionals wouldn’t have been possible without our determined and hardworking paddlers. The paddling lead, Josh Olson, led intense practices every weekend this year. Beginner-friendly open practices started in the fall. The entire team was encouraged to try it out to see if they liked it. The training started to progress as the year went on and the official paddling team was selected during winter quarter.

You’re probably curious about what exactly paddling involves, so I spoke with Ann Albright, who dominated the women’s endurance race at Regionals with teammate Sara Tari. They got the second fastest time in the whole competition for endurance races, after UW’s own men’s endurance team. She gave us a little “Paddling 101”:

How to paddle:

“The paddle is shaped like a spoon, you want the spoon facing away from you so that you can reach as far forward as possible. You twist, look under your top arm, and lean forward to get the furthest reach. Then you use your stomach and back muscles to straighten your body and draw the paddle through the water. This is not a bicep workout, you should be engaging your core.”

Josh, the paddling lead, provided the team with videos to help teach the proper technique. When you first start training, you just work on simple paddling technique. Once your form is second nature, you move into more complex maneuvers for turning.