Geological Engineering Commons^™

Regional Geomorphic Analysis And Gis Susceptibility Mapping Of Landslides In The Blue Nile And The Tekeze River Basins Of Ethiopia, Elamin Hassan Dai Ismail

Doctoral Dissertations

"The Plateau region of Ethiopia lies within a seismically active continental extensional regime, which is being rapidly incised by the Blue Nile and the Tekeze Rivers. Extremely large landslides pose serious hazards in this highly populated region (>27 million), which is in the process of developing its hydrologic resources. This research sought to develop cost-effective methods to compile regional landslide inventory and landslide susceptibility maps, using geomorphic tools and GIS technologies. This work also sought to evaluate the relationships between landslide dams and knickpoints, caused by channel bed incision from those caused by slope failures, by utilizing identified knickpoints …

A Regional Study Of Landslide Hazards And Related Features In The Upper Indus River Basin, Northern Pakistan, Muhammad Farooq Ahmed

Doctoral Dissertations

"A spatial landslide inventory is a fundamental step preparatory to developing an understanding of regional landslide hazards. The techniques honed for this regional landslide mapping study began with compiling a stitched shaded topographic map of the Upper Indus River watershed; using remotely-sensed topographic maps from Russia combined with ASTER DEM 30m resolution data. Topographic recognition keys were then employed to aid in the visual identification and delineation of past landslides, rockslide avalanches, and landslide dam sites. The first order reconnaissance level inventory excerpted 2,254 landslides (mostly deep seated translational and complex slides) along the main stem of Indus River, land …

Characterization Of Rabinal, Guatemala Clay And Development Of An Engineered Surrogate For The Purpose Of Laboratory Study, Lara Anne Hubbel

Masters Theses

"Ceramic pot filters (CPFs) have been proven to be an effective, low cost household water treatment system that are commonly used in third world countries. They are made using local clay, burn out material and colloidal silver or silver nitrate. Challenges faced by researchers include difficulty in acquiring filters from their manufacturing facilities without incurring damage and the cost of shipping. Acquiring the clay material used to make the filters is also difficult due to the cost of shipping and permits necessary to import soil. There have been studies conducted that compared laboratory made CPFs made with native clay and …

Joint Diagonalization Applied To The Detection And Discrimination Of Unexploded Ordnance, Fridon Shubitidze, Juan Pablo Fernández, Irma Shamatava, Benjamin Barrowes, Kevin O’Neill

Dartmouth Scholarship

Efforts to discriminate buried unexploded ordnance from harmless surrounding clutter are often hampered by the uncertainty in the number of buried targets that produce a given detected signal. We present a technique that helps determine that number with no need for data inversion. The procedure is based on the joint diagonalization of a set of multistatic response (MSR) matrices measured at different time gates by a time-domain electromagnetic induction sensor. In particular, we consider the Naval Research Laboratory’s Time-Domain Electromagnetic Multisensor Towed Array Detection System (TEMTADS), which consists of a 5×5 square grid of concentric transmitter/receiver pairs. The diagonalization process …

Estimating Land Surface Temperature Using A Thermal Sharpening Technique, Yitong Jiang, Qihao Weng

Symposium 2012

No abstract provided.

Impacts Of Changes In Land Use And Land Cover On Atmospheric Chemistry And Air Quality Over The 21st Century, S. Wu, L. J. Mickley, J. O. Kaplan, D. J. Jacob

Michigan Tech Publications, Part 1

The effects of future land use and land cover change on the chemical composition of the atmosphere and air quality are largely unknown. To investigate the potential effects associated with future changes in vegetation driven by atmospheric CO 2 concentrations, climate, and anthropogenic land use over the 21st century, we performed a series of model experiments combining a general circulation model with a dynamic global vegetation model and an atmospheric chemical-transport model. Our results indicate that climate-and CO 2-induced changes in vegetation composition and density between 2100 and 2000 could lead to decreases in summer afternoon surface ozone of up …

Microstructural And Mineralogical Transformation Of Hydraulically Disposed Fly Ash—Implications To The Environment, Jabulani S. Mahlaba, Elsabe P. Kearsley, Richard A. Kruger

Coal Combustion and Gasification Products Journal Archive

Increasing amounts of coal are combusted annually to meet the ever-increasing energy demands. The inevitable by-products include fly ash and saline effluents, which require acceptable disposal. The aim of this article is to compare the effect of hydraulic disposal with dry ash dumping. The results indicate that the former carries more environmental benefits based on the physical, chemical, and mineralogical aspects that were investigated.

Cordyline Fruticosa Growth And Soil Microbial Quality With Topical Application Of Coal Combustion By-Products Aggregates, Sangchul Hwang, Isomar Latorre, Eileen Irizarry

Coal Combustion and Gasification Products Journal Archive

Coal combustion by-products aggregates (CCAs) are a solidified composite of fly and bottom ashes (2:1, by wt). Here, we assessed the feasibility of beneficial use of CCAs as a soil amendment or conditioner by conducting an outdoor experiment with Cordyline fruticosa (lucky plant) to determine its growth and soil microbial quality under the influence of topical CCA application (95 tons ha21). Enhanced growth of C. fruticosa with CCA application was noted, with respect to plant height, growth rate, leaf size, and leaf chlorophyll intensity. Soil dehydrogenase activity and total heterotrophic bacteria count were greater with topical CCA application, especially in …

Influence Of Activator Solution Formulation On Fresh And Hardened Properties Of Low-Calcium Fly Ash Geopolymer Concrete, Carlos Montes, Erez N. Allouche

Coal Combustion and Gasification Products Journal Archive

The effect of the composition of activator solutions on fresh and hardened properties of geopolymer concrete was investigated. Research variables included liquid sodium silicate product (DH, NH, and StarH), sodium hydroxide molar concentration (6, 10, and 14), and sodium silicate–to–sodium hydroxide ratio (1, 2, and 3). Response variables were compressive strength, corrosion resistance expressed as remaining compressive strength and mass loss, and flowability. Results were analyzed using Minitab statistical software. Findings suggest that activator solution formulation has a significant effect on the properties of the resulting geopolymer binder. The experimental design used was found effective in establishing the optimum activator …

Mineralogical Transformations In Coal Feedstocks During Carbon Conversion, Based On Packed-Bed Combustor Tests: Part 2. Behavior Of Individual Particles, Ratale H. Matjie, Colin R. Ward, Zhongsheng Li

Coal Combustion and Gasification Products Journal Archive

Handpicked carbon-rich particles (coal or char), mineral-rich particles (heated stones), and bonded stone aggregates (clinkers) from the upper and lower parts of a pilot-scale packed-bed combustor bed, designed to simulate conversion or combustion processes, were subjected to mineralogical and inorganic geochemical studies, in order to evaluate the reactions that may occur during carbon conversion at a particle-by-particle scale. The mineral matter of the carbon-rich particles was found to have higher proportions of carbonate minerals and kaolinite than the mineral-rich (stone) particles in the coal feedstocks used in the study, and to form phases such as anorthite, gehlenite, pyrrhotite, troilite, and …

Mineralogical Transformations In Coal Feedstocks During Carbon Conversion, Based On Packed-Bed Combustor Tests: Part 1. Bulk Coal And Ash Studies, Ratale H. Matjie, Colin R. Ward, Zhongsheng Li

Coal Combustion and Gasification Products Journal Archive

Mineralogical and inorganic geochemical studies have been carried out on composite samples of six different coarse-crushed (,120 mm) feed coals tested in a pilot-scale packed-bed combustor designed to simulate conversion and some fixed-bed combustion processes, and also on composite samples of the ashes produced. The mineral matter of the coals consisted mainly of quartz, kaolinite, and Ca-bearing carbonate minerals (calcite, dolomite, aragonite), with minor proportions of illite, pyrite, and several other phases, along with some Ca in an organically associated form. The base to acid ratio of the coal ashes ranged from 0.1 to 0.3, due mainly to variations in …

Potential Indoor Air Exposures And Health Risks From Mercury Off-Gassing Of Coal Combustion Products Used In Building Materials, Christopher M. Long, Sonja N. Sax, Ari S. Lewis

Coal Combustion and Gasification Products Journal Archive

Coal combustion products (CCPs), including coal fly ash (CFA) and flue gas desulfurization (FGD) gypsum, have gained accepted use as substitutes for traditional substances in building materials. Because of the presence of mercury (Hg) in CCP materials, some concerns have been raised regarding the potential for Hg to off-gas from building materials into indoor air. Risk assessment offers a well-accepted, objective framework in which to determine whether such off-gassing could result in humanexposures of health concern. We thus conducted a screening-level human health risk assessment to estimate worst-case inhalation risks from indoor air exposures to Hg for multiple CCP utilization …

Quantifying The Benefits Of Using Flue Gas Desulfurization Gypsum In Sustainable Wallboard Production, Jin Cheol Lee, Sabrina L. Bradshaw, Tuncer B. Edil, Craig H. Benson

Coal Combustion and Gasification Products Journal Archive

Electric utilities produce more than 11.2 Mt of flue gas desulfurization (FGD) gypsum annually. Approximately 7.5 Mt is used in wallboard production. This article examines the environmental and cost benefits associated with replacement of natural gypsum in wallboard with FGD gypsum. A life-cycle analysis program was used to quantify the benefits of using FGD gypsum from electric power production in wallboard construction. Comparisons were made between energy consumption, water use, and greenhouse gas (GHG) emissions associated with obtaining and processing virgin gypsum material and those with FGD gypsum. The added impact of disposing of the unused FGD gypsum in landfills …

Waste Classification Of Slag Generated In A Pilot-Scale Entrained-Flow Gasifier, Ashleigh Cousins, Robin W. Hughes, David J. Mccalden, Dennis Y. Lu, Edward J. Anthony

Coal Combustion and Gasification Products Journal Archive

Series of gasification tests have been completed in the pilot-scale entrained-flow slagging gasifier at CanmetENERGY using Canadian coals, oil-sand coke, and blends of these fuels to determine if the produced slags are nonhazardous in nature. Solid wastes generated during these tests were analyzed for their trace metals, crystallinity, and toxic constituent leaching tendency in an attempt to provide more insight into the possibility of disposal or by-product use of gasifier-produced solid waste. The gasification tests were performed at conditions representative of commercial gasifiers using a dry-fuel-feed configuration. The lower-volatility elements were found to partition between the slag and process-water solids …

Influence Of Capillary Heterogeneity On Leakage Of Co2 From A Borehole, Frank Roecker

Electronic Theses and Dissertations

We used a modified invasion percolation (MIP) model to examine the effect of capillary heterogeneity, buoyancy forces, and viscous forces on the surface area and saturation of a CO2 plume leaking into a shallow aquifer. The purpose of this study is to provide a better understanding of how CO 2 migrates from a borehole, which is essential in implementing effective simulation and monitoring regimes to accurately detect CO2 leakage from sequestration sites. The MIP model approach will simulate invasion of a light non-wetting fluid (e.g., CO2) into a medium initially saturated with a dense wetting fluid (water). The style of …

Capture Zone Modeling For Photovoltaic Microgrid Powered Pump And Treat Remediation, John Patrick Conroy

Masters Theses

"Remediation systems protect human health and the environment by removing harmful contaminants from the environment. Pump and treat groundwater remediation systems typically rely on utility power to continuously pump contaminated groundwater to an above ground treatment unit. However, the use of renewable energy (solar and wind) for a pump and treat remediation system can reduce the output of harmful greenhouse gases and the need for coal-based utility power.

This paper describes a hypothetical renewable energy powered pump and treat remediation system that uses an off-grid photovoltaic array to power a submersible solar water pump. The pump operates on an intermittent …

The Use Of Electrical Resistivity Tomography (Ert) To Delineate Water-Filled Vugs Near A Bridge Foundation, Jeremiah Chukwunonso Obi

Masters Theses

"A structural support was needed to strengthen the load-bearing capacity of an unnamed bridge foundation in Laclede County in South-Central Missouri due to increasing traffic volume and age of the bridge. This area is characterized by karstic features such as losing streams, underground caves and sinkholes. During the construction of a drilled shaft for the substructure, a few feet north of the north footing of the pier, voids were noted beneath a roughly 2 foot thick cap of dolomite rock. Because of this, there were concerns about the integrity of the rock beneath the existing bridge foundation. Consequently, subsurface investigation …

Analyses Of Surface Wave Seismic Data And Supplemental Borehole And Electrical Resistivity Tomography Control, Mengxing Li

Masters Theses

"Multichannel analyses of surface wave (MASW) data and electrical resistivity tomography (ERT) control were acquired at two test sites in central Missouri. Limestone bedrock existed at both test sites at variable depths. The ground surface at both test sites was relatively flat.

The primary objective was to map the variable depth to the top of the rock based on shear-wave velocity contrasts. ERT data and borehole control were acquired at each site in order to constrain the interpretation of the MASW data.

The MASW method proved to be more effective than the ERT method in terms of mapping soil layers …

Performance Characterization And Optimization Of Microgrid-Based Energy Generation And Storage Technologies, Joe D. Guggenberger Ii

Doctoral Dissertations

"Renewable energy-powered microgrids have proven to be a valuable technology for self-contained (off-grid) energy systems. Characterizing microgrid system performance pre-deployment would allow the system to be appropriately sized to meet all required electrical loads at a given renewable source operational time frequency. A vanadium redox battery was empirically characterized to determine operating efficiency as a function of charging characteristics and parasitic load losses. A model was developed to iteratively determine system performance based on known weather conditions and load requirements. A case study was performed to compare modeled system performance to measurements taken during operation of the microgrid system. Another …

Saturation Effects On Mechanical Excavatability Of Roubidoux Sandstone Under Selected Rock Cutting Tools, Muhammad Zubair Abu Bakar

Doctoral Dissertations

"This study investigated the differences in the cutting performance of two rock cutting tools in dry and saturated rock. For this purpose, a permeable quartzose sandstone was subjected to a series of full scale linear rock cutting tests, in both dry and saturated conditions, using a constant cross-section (CCS) disc cutter and a radial drag pick at a constant cutting speed.

In this rock, saturation with water reduced the forces acting on the disc cutter by 27-48% (significant at 90% confidence), but also reduced the chip yield by nearly as much. Even though the specific energy of fragmentation went down …