rmsst student showcase
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RMSST Student Showcase. Joshua Baker 11 th Grade February 11, 2014. Optimization of Concrete Composites using CCBs as Additives. Introduction. Each year, hundreds of millions of tons of coal-fired power plant waste is dumped into landfills - PowerPoint PPT PresentationTRANSCRIPT
Joshua Baker
11th Grade
February 11, 2014
RMSST Student
Showcase
Optimization of Concrete Composites using CCBs as Additives
• 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
Introduction
Image 1: A coal waste landfill in Henrico County, VA
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
Introduction
• 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
Background
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.
Procedures – Air Content
Image 3: Unit Weight container with Air Content gauge attached
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.
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).
Control Fly Ash Bottom Ash0
10000
20000
30000
40000
50000
60000
70000
80000
90000
100000
54606.6666666667 55350
42946.6666666667
79870
93276.67
73530
Average Ultimate Load
Ultimate Load (lb) - Day 7Ultimate Load (lb) - Day 56
Figure 1: The average ultimate load of each composite mix, which is a direct measurement the maximum load a sample can withstand before fracturing.
Control Fly Ash Bottom Ash0
1000
2000
3000
4000
5000
6000
7000
8000
4343.33333333333 4403.33333333333
3416.66666666667
6356.67
7420
5850
Average Compressive Strength
Compressive Strength (psi) - Day 7Compressive Strength (psi) - Day 56
Figure 2: The average compressive strength of each composite mix, a calculated measurement of the maximum force a sample can withstand before fracturing.
Control 25% Class C Fly Ash 25% Bottom Ash0
0.5
1
1.5
2
2.5
2
1.2
2.1
Air Content
Mix Type
Air
Cont
ent
(%)
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.
Control 25% Fly Ash 25% Bottom Ash0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
3.5 3.5
4.25
Slump
Mix Type
Slum
p (in
ches
)
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.
Control 25% Class C Fly Ash 25% Bottom Ash136
138
140
142
144
146
148
150
152
147.6146.4
141.7
149.8150.7
145.8
Density
Target DensityMeasured Density
Mix Type
Den
sity
(lb
/f3)
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.
• 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
Data Trends and Analysis
• 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
Discussion and Conclusion
• Determining the chemical leaching capability of CCBs and their flammability at different burn stages
• Investigating the environmental effects of using CCB-containing concrete composites
Future Research
RMSST:• John Hendrix
TEC Services:• Steven Maloof and Technicians• Brian Smith• Brian Wolfe
Ernst Enterprises of Georgia:• Tony Dowdy
Acknowledgements
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.pdfConcrete tests. (2003, September 01). Retrieved from http://www.dot.state.mn.us/materials/manuals/concrete/Chapter5.pdfEPA – Coal Combustion Products. (May 2013). Retrieved from http://www.epa.gov/wastes/conserve/imr/ccpsKalyoncu, R. S. (2000). Retrieved from website: http://minerals.usgs.gov/minerals/pubs/commodity/coal/874400.pdfKosmatka, 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/0Sahu, 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
References
• 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
Achievements - GHP
• 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
Achievements – AP Exams