RMSST Student Showcase

1. RMSST Student Showcase Joshua Baker 11th Grade February 11, 2014

2. Optimization of Concrete Composites using CCBs as Additives

3. Introduction • Each year, hundreds of millions of tons of coal-fired power plant waste is dumped into landfills • Has potential to leach into groundwater and contaminate water supplies • Little is ever reused, though much of it can be • Carbon footprint can be greatly reduced if some byproducts are reused Image 1: A coal waste landfill in Henrico County, VA

4. Introduction • Purpose • To determine the structural impact of coal combustion byproduct additives at the “optimal” replacement rate, 25-30% • Rationale • Management of CCBs in coal-reliant nations must be addressed before they pose an environmental hazard • Concrete is a versatile building material with potential for integration of numerous additives • Successfully using CCBs as additives at a 25% replacement rate would greatly decrease human environmental impact and provide a strong, environmentally responsible composite that can be adapted to new uses

5. Background • Independent Variable: Concrete Composition • Dependent Variable: Concrete Performance • In an ongoing experiment, it is being determined whether it is plausible to create cement-free concrete using geopolymers, eliminating the CO2 released when normal concrete hardens

6. Procedures – Concrete Mixing Image 2: Mixes 1 (Portland Cement, Sand, Stone) and 2 (75% Portland Cement, 25% Class C Fly Ash, Sand, Stone) in their mid-mixing stages.

7. Procedures – Air Content Image 3: Unit Weight container with Air Content gauge attached

8. Procedures - Slump Image 4: Slump test; the bottom of the metal rod (right) is used as the starting point for determining how far the concrete falls and spreads out.

9. Procedures – Compressive Strength Image 5: The hydraulic press, used for compressive strength testing (right); an example of Class 5 fracturing (left) and Class 2 fracturing (center).

10. Figure 1: The average ultimate load of each composite mix, which is a direct measurement the maximum load a sample can withstand before fracturing.

11. Figure 2: The average compressive strength of each composite mix, a calculated measurement of the maximum force a sample can withstand before fracturing.

12. Figure 3: The percentage of air entrained in a unit of concrete, 1 ft3. The percentage of air in a mixture contains impacts both the flexural strength and the overall weight of the concrete.

13. Figure 4: The measured slump of each concrete mix, a measurement of mix consistency. This variable is most significant when comparing mixes of similar composition.

14. Figure 5: The calculated (blue) and target (red) densities of each mix, a measure of the mass of a cubic foot of a given mix design. It is used when determining factors that influence the strength of concretes.

15. Data Trends and Analysis • Group 2 (Fly Ash additive) outperformed control in ultimate load/compressive strength tests at both testing times • Group 3 (Bottom Ash additive), on average, performed either similarly to (Day 56) or worse than (Day 7) the control in ultimate load/compressive strength tests • Fly ash group continues to show trend of gaining strength over long periods of time

16. Discussion and Conclusion • Based on the currently available data from experimentation and from data analysis, Mix 2 performed within the 20% margin of similarity to the control for its average compressive strength and ultimate load, thus rejecting the null hypothesis • The data gathered for Mix 3 performed outside of this margin, supporting the null hypothesis • Final ultimate load and compressive strength data will be collected at the 90 Day curing point

17. Future Research • Determining the chemical leaching capability of CCBs and their flammability at different burn stages • Investigating the environmental effects of using CCB-containing concrete composites

18. Acknowledgements RMSST: • John Hendrix TEC Services: • Steven Maloof and Technicians • Brian Smith • Brian Wolfe Ernst Enterprises of Georgia: • Tony Dowdy

19. References • Bumjoo, K., Prezzi, M., & Salgado, R. (2005, July). Geotechnical properties of fly and bottom ash mixtures. Retrieved from https://engineering.purdue.edu/~mprezzi/pdf/10900241_geotechnical_properties.pdf • Concrete tests. (2003, September 01). Retrieved from http://www.dot.state.mn.us/materials/manuals/concrete/Chapter5.pdf • EPA – Coal Combustion Products. (May 2013). Retrieved from http://www.epa.gov/wastes/conserve/imr/ccps • Kalyoncu, R. S. (2000). Retrieved from website: http://minerals.usgs.gov/minerals/pubs/commodity/coal/874400.pdf • Kosmatka, S. H., & Wilson, M. L. (2011). Design and Control of Concrete Mixtures: The Guide to Applications, Methods, and Materials. (15th ed.). Washington, DC: Portland Cement Association. • Mohanty, M. K., & Kumar, S. U.S. Environmental Protection Agency, (2011). Sustainable Utilization of Coal Combustion Byproducts through the Production of High Grade Minerals and Cement-less Green Concrete. Retrieved from website: http://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/9588/report/0 • Sahu, S. P. (2010). Characterization of Coal Combustion By-products (CCBs) for their Effective Management and Utilization. (Bachelor's thesis) Retrieved from http://ethesis.nitrkl.ac.in/1708/1/final_thesis_edited.pdf

20. Achievements - GHP • Nominated to attend the Governor’s Honors Program for Chemistry • Prestigious program that bolsters student • interest in their nomination areas • This program will provide valuable insight into • my field of interest, and help when deciding • how future years will be spent

21. Achievements – AP Exams • 4 on the AP Biology Exam • 3 on the AP World History Exam • Shows how my work ethic and study skills have improved as my time at Magnet progressed