Master of Science, The Ohio State University, 2023, Environment and Natural Resources

Since the beginning of time Earth's carbon cycle has self-regulated, experiencing periods of warming and cooling with changing amounts of carbon in the atmosphere. Today, human activity is rapidly changing the climate through the addition of greenhouse gases to the atmosphere like carbon dioxide (CO2). To prevent disastrous outcomes caused by climate change, it is vital to halt greenhouse gas emissions, however, this is only one part of the solution. To keep global temperatures from increasing more than 2° C, CO2 removal must also be an integral part of the solution. The objectives of this research were to conduct a laboratory experiment and investigate the carbonation of concrete within soil as a viable option to sequester atmospheric carbon, analyze how concrete carbonation changes with fragment size, and understand the environmental impacts of adding concrete to soil. Soil samples from Waterman Agricultural and Natural Resources Center were collected and placed into 30 cm columns with different mixtures of crushed recycled concrete to test concrete in soil as an enhanced weathering material. Four different treatments were tested and were comprised of 1) 100% soil (S samples), 2) 90% soil and 10% concrete by weight of 0.25-0.71 mm diameter fragments (F samples), 3) 90% soil and 10% concrete by weight of 8 mm diameter fragments (L samples), and 4) 100% concrete composed of 8 mm diameter fragments (C samples). Four replications of each treatment were tested for a total of 16 samples. Approximately 40 cm3 of deionized water was added to each sample every day from a drip irrigation system for a total amount of 940-990 mm yr-1 throughout the experiment to simulate the amount of precipitation received by Columbus, OH in one year, with leachate continuously collected underneath the columns. After 16 weeks, the soil and concrete mixtures were removed from the columns and tests were conducted on the soil and leachate samples. The results from this study show that con (open full item for complete abstract)

Committee: Rattan Lal (Advisor); Berry Lyons (Committee Member); M. Scott Demyan (Committee Member); Matt O'Reilly (Committee Member) Subjects: Civil Engineering; Climate Change; Environmental Science; Soil Sciences