Engineering Commons^™

A Hydrologic Climate Study For An Arid Region, Ali Alsubeai

Electronic Theses and Dissertations

Water is the most precious natural resource in arid regions due to the limitation of water resources, expanding population, and increasing volumes of industrial and domestic waste. The purpose of this research was to evaluate methods to estimate water quantity in an arid region. The research consisted of three separate studies. In the first study, hydrologic models used to estimate water quantity were evaluated for suitability of use in arid regions. Most hydrologic models that have been used in arid regions were originally developed for humid regions. Rainfall events in arid regions can be characterized as short-term, high intense rainstorms …

Computational Modeling Of Climate Attributes And Condition Deterioration Of Concrete Highway Pavements, Salma Sultana

Electronic Theses and Dissertations

An efficient and safe road network secures the nation’s economy and prosperity by providing public mobility and freight transport. Maintenance and rehabilitation of the road network cost billions of dollars annually. Road and highway infrastructures performance in any country is impacted by load repetitions and it is further compromised by climate attributes and extreme weather events. Damages to roads and bridges are among the infrastructure failures that have occurred during these extreme events. If maintenance and rehabilitation are not done promptly, the damages to the road caused by heavy traffic and extreme climate may lead to life-threatening conditions for road …

Laboratory Measurements Of Bed Shear Stress In Open Channel Flow And Soil Erosion Rate In Cohesive Soils, Gunnar Schurmann Kern

Electronic Theses and Dissertations

The relationship between soil erosion rate and bed shear stress is an important problem in sediment transport and scour. However, reliable measurements of the soil erosion function are challenging, both in the field and in the laboratory. The objective of this study is to investigate an experimental setup for conducting bed shear stress and soil erosion rate measurements using an open channel flume with a rough bed. These experiments were performed in an A-8 Hydraulic Channel with a fixed gravel bed. The flow discharge was kept constant at 0.158 ft.3/s, and bed shear stress was varied by changing the channel …

Nitrate And Phosphate Removal From Denitrification Bioreactors Using Woodchips, Steel Chips And Agricultural Residue Media, Abdoul Aziz Kouanda

Electronic Theses and Dissertations

Nitrate and phosphate present in agricultural subsurface drainage water can impact surface water quality thus impacting the environment and human health by causing eutrophication and Methemoglobinemia in young infant. Biological denitrification and phosphate adsorption filters are treatments options that can help reduce nitrate and phosphate concentration from agricultural subsurface drainage before it can be discharged in surface water. The first objective of this dissertation was to determine the Michaelis-Menten kinetics model parameters for nitrate removal in bioreactors using the fresh, aged, and composted woodchips. The composted woodchips achieved a denitrification rate 2.4 times higher than the fresh woodchips which was …

A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu

Electronic Theses and Dissertations

The increasing application of geographic information system (GIS) technology in watershed modeling makes is necessary to further evaluate its impacts on runoff characteristics as a basis for improved hydrologic analysis in ungauged watersheds. Experts in the field of water resources and hydrology have recommended the practice of subdivision when modeling a watershed, and the use of observed data from hydrologically similar watershed to calibrate and validate an ungauged watershed’s model. However, previous studies have failed to adequately address the issues of watershed heterogeneity, spatial and temporal variability in physical parameters, GIS data resolution issues, including artifacts in automated extraction of …

Impact Of Blended Salt Anti-Icers/Deicers On Properties Of Asphalt Binders, Nurudeen A. Abidoye

Electronic Theses and Dissertations

Anyone who has ever attempted to remove a layer of ice from a roadway or sidewalk by plowing or shoveling knows it is no easy task when the ice is firmly bonded to the asphalt/concrete surface. Winter anti-icing/deicing operations are moral choices that mankind has made to combat winter storms. This research is aimed at evaluating the macro and nano structural impacts of (anti-icing/de-icing) salt on aged and unaged asphalt binders. The macro structural impacts focused on the rheological and creep properties, and the nano structural impacts focused on the surface topography, adhesion force, and modulus of asphalt binders. Rheological …

A Speciation Modeling Study Of Heavy Metal Adsorption To Plastic In Municipal Wastewater Treatment Plant Units, Kaitlyn Hague

Electronic Theses and Dissertations

Microplastics are an emerging concern due to their harmful effect to organisms and their ability to facilitate transport of contaminants including heavy metals. Microplastics can enter the environment through wastewater treatment plants, landfill leachate, and littering. Once in the environment microplastics can be distributed throughout rivers, the ocean, and lakes. In order to understand the adsorption of heavy metals to microplastics a geochemical modeling study was completed using Visual Minteq. Lab tests were completed to better understand what constituents are available in wastewater at four different locations: influent, clarifiers, digesters, and effluent. These constituents were then used to observe how …

A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani

Electronic Theses and Dissertations

Climate variability is an important subject to study. It is the change of climate over a long time, which could have a positive or negative impact on humans, soil, and wildlife. Many environments, such as arid environment could be affected by climate variability. The research goal is studying and examining climate variability in arid environment. The research includes three different studies. The first study includes reviewing and understanding of climate variability over extended time through existing studies in arid environments. In addition, this study includes knowledge about climate negative or positive impact on the environment. This study will be reviewing …

Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh

Electronic Theses and Dissertations

Excessive algal growth in freshwater lakes can negatively impact ecosystems, recreation, and human health. Though algae are a natural part of freshwater ecosystems, elevated nutrient loading from anthropogenic and natural sources can lead to algal blooms. Both algae and blue-green algae (BGA) are responsible for algal blooms; however, BGA (cyanobacteria) is more dangerous. The first objective of this research was to prepare a conceptual model to understand how various environmental variables affect algae. This conceptual model was used to choose the environmental variables that help increase or decrease algae in the water environment. The second objective was to develop empirical …

Long Term Evaluation Of E. Coli Removal From Stormwater Using Recycled Steel Byproducts, Brenden Olevson

Electronic Theses and Dissertations

Stormwater runoff often carries a variety of pollutants and pathogens that can endanger public health and wildlife. One contaminant of concern often highlighted in stormwater quality is Escherichia Coli (E.Coli) because its presence indicates microbial contamination in water. Different types of media filtration are being studied to reduce contaminant concentrations in stormwater. In this study, steel byproducts were examined as a potential material to use in media filtration to remove E. Coli and other contaminants from stormwater. Batch scale studies were conducted in laboratory to evaluate the E. Coli removal potential of steel chips and steel slag over a 24-hour …

Seismic Performance Of Mechanically Spliced Precast Bridge Columns With New Couplers, Evan Greeneway

Electronic Theses and Dissertations

Lap splicing is not always the most economical or practical approach to achieve reinforcement bar continuity. Mechanical bar splices, or bar couplers, are one alternative that may be far more practical. Currently, the US codes do not allow for the use of bar couplers in the plastic hinge region for RC members in areas of high seismic activity. There has not been enough research into the couplers behavior when subjected to significant inelastic lateral deformations. The Lohr Structures Laboratory was used to conduct an experimental study on campus of South Dakota State University to evaluate the seismic performance of mechanically …

Effectiveness Of Seismic Bearings On A Typical Isolated Two-Column Rc Bridge Pier Located In North Mississippi, Hemant Raj Joshi

Electronic Theses and Dissertations

The 2020 ASCE infrastructure report card has assigned a letter grade of D- for bridges in Mississippi based on poor to fair condition ratings with many approaching the end of their useful service lives. Bridges in northern Mississippi lie up to 100 miles from the New Madrid Fault and fall into the Region 3 Seismic Performance Category defined by AASHTO. The primary objective of this study is to evaluate the performance of commercially available bridge bearings on a common bridge pier type used in northern MS under the combined action of superstructure gravity and lateral seismic loads. The use of …

Forecasting Geotechnical Parameters From Electrical Resistivity And Seismic Wave Velocities Using Artificial Neural Network Models, Fatema Tuz Johora

Electronic Theses and Dissertations

Geotechnical measurements of soil parameters used in the design of infrastructure provide information at a specific point of the ground. The use of limited point data may result in greater uncertainty and less reliability in design. Geophysical methods are non-invasive, less time-consuming, and provide continuous spatial information about the soil. However, geophysical information is not in terms of engineering parameters. Correlations between geotechnical parameters and geophysical parameters are needed to facilitate the use of geophysical information in geotechnical designs. The current research is focused on two geophysical methods; electrical resistivity (ER) and seismic wave velocity (S-wave and P-wave). Artificial neural …

Electromagnetic Survey Design Using Artifical Neural Networks, Shariful Islam Sharif

Electronic Theses and Dissertations

Acquiring geophysical information requires selection of the geophysical method based upon the defining physical property and a survey design with adequate resolution but cost effective based upon the size of the area to be surveyed. The objective of this study is to use artificial neural nets (ANNs) to design an optimal survey. The developed approach is tested for the case of soil pipe surveying using electromagnetics. Soil pipes are tortuous voids located within 1.5 m depth of the ground surface. They trend perpendicular to the slope and have cross-sectional dimensions on the order of millimeters to tens of centimeters. The …

New Longitudinal Error Balancing Approaches For Closed Traverses, Jose L. Manzano

Electronic Theses and Dissertations

This study presents two novel approaches to balance the horizontal longitudinal error of closure, E_C, in closed polygonal traverses. The standard procedure to balance E_C is the Compass Rule. This technique reduces E_C to zero by applying corrections in the lengths of all traverse sides. Those corrections are proportional to the corresponding side lengths. That is, this approach is not an error-correcting approach, but an error-balancing procedure.

The proposed new techniques are based on sensitivity analysis of E_C with respect to small variations, Δ_i, in the lengths of all sides i = 1, …

Current Status Of Design And Construction Of Piles With A Pilot Hole On Rock, Charles C. Crowner

Electronic Theses and Dissertations

Driven piles at project sites get their load bearing capacity from side friction along the driven lengths as well as from end resistance. Pilot holes is a pile driving assistance method used to aid driving displacement piles through hard/ dense layers and rock. These pilot holes can be a size smaller or larger than the pile that is to be installed. The pilot hole is first drilled down to a specific depth. The use of a pilot hole reduces the “end bearing” and “side resistance” within the drilled zone and aids the driving of the pile. This process also complicates …