Athens, OH 8 December 2013 – During the past two years I have been involved with American society of Civil Engineers (ASCE) and every year in March we compete against other schools in Ohio, Pennsylvania, and Kentucky with our concrete canoes. Yes, we make concrete float and race them with up to 4 people in the canoe.
Although the competition isn’t until March, we spend the entire school year preparing by constructing a mold and designing a new concrete mix because the specifications change every year. The past two years we have tried to do something we have never done before. Last year we did an injection mold and this year we are using per stressed wires.
Per stressed wires is something we wanted to give a try but problems keep showing up for our first test. First, we had to come up with a way of keeping the wires from being pulled out of the concrete after the tension is released. We need to have some object attached to the wire that will not move and provide contact points throughout the concrete walls. So we decided to use crimping nuts.
Secondly, we need to keep the wires off the mold so that they are in the middle of the wall to provide the best strength. We have decided to use flat head screws and drill them into the mold at a desired distance and the wire will rest in the grove of the screw head. Finally, we need to add about 100 to 150 pounds of tension to the 18 wires. We have decided to go with using a turn buckle to reach the right tension. A scale model with all of our solutions will be conducted the beginning of spring semester.