As a member of Duke’s American Society of Civil Engineers (ASCE), I played an integral role in the making of Duke’s concrete canoe. The goal purpose of the project is to create a canoe out of concrete which is able to be raced at competitions all over the country. This page discussed the way the canoe was constructed in my first two years at college. In 2018, I developed a new method to constructing the mold which you can read about here.
The first semester of the year was spent concocting the mix used for the concrete. Every week we would try a new combination of materials and tested how the concrete performed. The two major design criteria we were optimizing were material strength and material weight. The lighter the canoe is, the better it will be able to float and the faster we could race it. The material also had to be strong to maintain its form and so that we would be able to use less material.
Each week we would create a new mix, and test the strength of the material from the previous week. Below is an image of concrete cylinders used to test the strength of the concrete.
In the second semester, we had to build the canoe. We chose the best mix we had developed in the first semester and began building the frame of the canoe. We used a stencil to cut wooden arches into the desired cross sections. We then determined the spacing of these sections and attached them in a row as shown below.
With the form established, we attached plastic supports across the length of the canoe.
On top of these supports, we attached foam boards upon which we were able to place the concrete. Then a mesh layer was laid on top of the concrete before the second layer of concrete was added. Below is a cross section of what the final product looked like, layer by layer.
After a grueling day of mixing concrete, measuring materials, and laying concrete, we had created a full sized canoe.