Building formwork for the new test setup
Author: Brenden Simmons | Major: Civil Engineering | Semester: Fall 2022
Brenden Simmons is a senior honors student in the College of Engineering. Upon graduation in May 2023, Brenden will receive a bachelor’s degree in civil engineering with a minor in general business. Under the mentorship of Dr. Cameron Murray, Assistant Professor in the Department of Civil Engineering, Brenden has conducted his research on the bond strength of BCSA Concrete in repairing applications. Upon completion of this research, he will develop an honors thesis based on the final results.
When I started to take civil engineering classes at the University of Arkansas, I quickly developed an interest in concrete. One of the best qualities of the professors in the Department of Civil Engineering is their ability to create hands-on learning experiences for their students. As I started to think about research topics for my honors thesis, I knew I wanted to do something with concrete. I had heard about some of the research that Dr. Murray was doing, and it sounded like something I would be interested in. He was doing a lot of work with belitic calcium sulfoaluminate cement (BCSA) concrete, which is a type of rapid-set concrete that reaches its working strength quicker than traditional portland cement concrete. After looking into some of Dr. Murray’s research, I met with him and asked if I could help him with some of his research and develop an honors thesis based on the results. Dr. Murray loved the idea, and we talked about how there was a need for us to understand the bond strength of BCSA concrete in repairing applications.
When a concrete structure needs to be repaired, it is essential to perform the repair as quickly as possible. Many broken structures can be a safety hazard, especially if they are above level ground. Bridges are a good example of this. In addition, the operation of these structures must be suspended until the repair is complete. If a bridge is shut down for an extended period of time, this slows down traffic. If the time it takes to repair the bridge can be decreased, then the total economic cost of the repair also decreases. Therefore, it is advantageous to use a type of cement that will allow the concrete to set as quickly as possible. BCSA concrete may be the ideal candidate. However, the setting time will not matter if the BCSA concrete is unable to effectively bond with the original material. At the end of the day, the composite material must be able to hold the loads that the bridge was designed to hold.
My research began this past summer. I worked closely with Elizabeth Poblete, a graduate research assistant for the Department of Civil Engineering, who is also conducting research on BCSA concrete. We began testing the shear strength of BCSA concrete with traditional Portland cement (PC) concrete at a small scale. We performed slant shear tests on several small cylinders. The details of this research can be found in my previous post, and the results will be highlighted in my thesis. The goal for my research during the fall semester was to test the bond strength of BCSA concrete at a greater scale. We were able to design a test setup that would allow us to test the bond strength for a large block of concrete. We were able to build the necessary formwork and lay the base layer of concrete for these tests. When we run this test, we will also be able to see how the bonds perform based on different finishes. This will give insight as to whether one should take the time to finish the concrete substrate a specific way before applying a repair layer. In the spring semester, we will be able to complete these tests and compile the results. I am extremely thankful for the opportunity to perform research in an incredible department with wonderful people!