Sustainability and Beneficial Use of Waste Materials
The first major research and teaching thrust in my group has focused on sustainability and beneficial use of coal combustion products and dredge materials. This work is performed in conjunction with Dr. Kim Kurtis’ research group, and focuses on the full life cycle of a variety of waste materials, including off-specification high carbon content fly ashes, biomass fly ashes, co-combusted biomass/coal fly ash, and ponded ash. Our work is multi-scale and ranges from micro-scale chemical and physical characterization of the waste materials in order to elucidate fundamental mechanisms of behavior at the particle level, including small strain behavior of off-specification ashes as a function of their organic content, through to scale-up of the mechanistic behavior and quantification of bench scale performance of construction materials composed of waste materials.
- Wirth, X., Benkeser, D., Yeboah, N.N., Shearer, C.R., Kurtis, K.E., and Burns, S.E. (2019). Evaluation of Alternative Fly Ashes as Supplementary Cementitious Materials, ACI Materials Journal 116 (4).
- Wirth, X., Glatstein, D., and Burns, S.E. (2019). Mineral phases and carbon content in weathered fly ashes, Fuel, Vol. 236, pp. 1567- 1576.
- Renew, J.E., Huang, C.H., Burns, S.E., Carrasquillo, M., Sun, W., and Ellison, KM. (2016). Immobilization of Heavy Metals by Solidification/Stabilization of Co-Disposed Flue Gas Desulfurization Brine and Coal Fly Ash, Energy & Fuels 30 (6), 5042-5051.
- Choo, H., Yeboah, N.N. and Burns, S.E. (2015). Small to Intermediate Strain Properties of Fly Ashes with Various Carbon and Biomass Contents, Canadian Geotechnical Journal, Volume: 53, Issue: 1, Pages: 35-48.
Erosion, Infiltration, and Stormwater Treatment on
Georgia Department of Transportation Rights-of-Way
My research group has a significant body of work on issues related to the transport of water on Georgia Department of Transportation rights-of-way. My students and I focus on aspects of erosion due to raindrop impact and surface water runoff, infiltration of surface water into stormwater Best Management Practices (BMPs), and development and enhancement of methods for the treatment of contaminated roadway runoff. Our work has demonstrated that the geochemical conditions of stormwater runoff, including pH and ionic strength, can have significant impact on the clogging of soil filters due to aggregation and flocculation of fine grained clay mineral particles in the runoff, and alteration, or geochemical control, of these parameters can result in retention or flushing of solids from BMPs that rely on solid/liquid separation as a treatment method. In addition, our group demonstrated the significant impact that immobilized colloidal particles can have on the transport of heavy metals through soil filters, especially when coupled with changes in the prevailing geochemical conditions (e.g., increased ionic strength due to road deicing).
- Won, J., Choo, H., and Burns, S.E. (2020). Impact of Solution Chemistry on the Deposition and Breakthrough Behaviors of Kaolinite in a Silica Sand, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 146, No. 1, https://doi.org/10.1061/(ASCE)GT.1943-5606.0002199.
- Won, J., Wirth, X., and Burns, S.E. (2019). An experimental study of cotransport of heavy metals with kaolinite colloids, Journal of Hazardous Materials 373, 476-482.
- Choo, H., Won, J., Park, K., Won, J., and Burns, S.E. (2018). Resistance of coarse-grained particles against raindrop splash and its relation with splash erosion. Soil & Tillage Research, Vol. 184, pp 1-10.
- Won, J. and Burns, S.E. (2018). Stochastic modeling of kaolinite transport through a sand filter, Canadian Geotechnical Journal, 10.1139/cgj-2018-0394.
- Won, J. and Burns, S.E. (2018). Role of Immobile Colloids in the Transport of Heavy Metals, Environmental Science and Technology, 52 (5), pp 2735–2741, 10.1021/acs.est.7b05631.
- Won, J. and Burns, S.E. (2017). Influence of Ionic Strength on Clay Particle Deposition and Hydraulic Conductivity of a Sand Medium, Journal of Geotechnical and Geoenvironmental Engineering, 143 (10), 04017081.
Bio-mediated Ground Improvement
Bio-mediated ground improvement is a research thrust that my group has initiated and developed over the last five years. Our work focuses on ground improvement using Microbially Induced Calcite Precipitation (MICP), relying on biostimulation and colloidal transport to optimize the precipitation and distribution of calcite within sandy soils. Precipitation of calcite from solution is driven in large part by nucleation mechanics, which is primarily heterogeneous nucleation at sites on the surface of soils or adhered bacteria surface; therefore, an increase in nucleation sites may effectively increase the rate of calcite deposition, the uniformity of calcite formation throughout the coarse medium, as well as the total amount of calcite deposition, even though it does not increase the urease activity. Most recently, we have received funding for a joint (with ASU and UCD) center-to-center grant with two Irish science centers from the Republic of Ireland and Northern Ireland to extend the technology to carbonate based soils.
- Won, J., Jeong, B., Lee, J., and Burns, S.E. (submitted 2019). ” Facilitation of Microbially Induced Calcite Precipitation with Kaolinite Nucleation”, Geotechnique, submitted.
- Saneiyan, S., Ntarlagiannis, D., Ohan, J., Lee, J., Colwell, F., Burns, S.E. (2019). Induced polarization as a monitoring tool for in-situ microbial induced carbonate precipitation (MICP) processes, Ecological Engineering. 127, pp. 36-47.
Fundamental Chemical and Engineering Behavior of Soils
The fourth major research thrust in my group has focused on the fundamental engineering behavior of soils. Because soils are frictional, particulate materials, with variable strength properties that depend on the particle-to-particle interfacial characteristics, work in this thrust area has studied a range of geochemical interfacial properties (e.g., iron oxides, organic compounds, contaminants). Our research includes fundamental experimental, analytical, and numerical studies on the static and dynamic engineering behavior of these soils, where both mechanical and chemical behaviors have been quantified. During the last five years, we have focused on determining soil stiffness and hydraulic properties from particle morphology and packing, as well as behavior of montmorillonite coated with soft organic matter.
- Won, J., Park, J., Choo, H., and Burns, S.E. (2019). Estimation of saturated hydraulic conductivity of coarse-grained soils using particle shape and electrical resistivity, Journal of Applied Geophysics 167, 19-25.
- Choo, H., Lee, W., Lee, C., and Burns, S.E. (2018). Estimating Porosity and Particle Size for Hydraulic Conductivity of Binary Mixed Soils Containing Two Different Sized Silica Particles, Journal of Geotechnical and Geoenvironmental Engineering, 144 (1), 04017104.
- Zhao, Q. and Burns, S.E. (2017). Molecular Simulation of Electrokinetics of Montmorillonite Surface Coated with Hexadecyltrimethylammonium Cations, Colloids and Surfaces, 516, p.354-361.
- Zhao, Q., Choo, H., Bhatt, A., Burns, S.E., and Bate, B. (2017). Review of the Fundamental Geochemical and Physical Behaviors of Organoclays in Barrier Applications, Applied Clay Science, 142 (15), pp. 2-20, https://doi.org/10.1016/j.clay.2016.11.024.
- Choo, H. and Burns, S.E. (2015). Shear wave velocity of granular mixtures of silica particles as a function of finer fraction, size ratios and void ratios, Granular Matter, Vol. 17, Issue 5, pp. 567-578.
- Choo, H., Bate. B, and Burns, S.E. (2015). Effects of organic matter on stiffness of overconsolidated state and anisotropy of engineered organoclays at small strain, Engineering Geology, 184(14), 19-28, doi:10.1016/j.enggeo.2014.10.022.