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Articles 151 - 180 of 471
Full-Text Articles in Civil and Environmental Engineering
Developing More Efficient Mechanically Stabilized Earth (Mse) Wall Reinforcements, Matthew J. Rahmeyer
Developing More Efficient Mechanically Stabilized Earth (Mse) Wall Reinforcements, Matthew J. Rahmeyer
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The most common shape for metallic reinforcement in Mechanically Stabilized Earth (MSE) walls is a rectangular strip. The amount of force required to pull the reinforcement out of the wall versus how much steel is required is well balanced.
This study shows that a metal round bar can be altered, either by bending into various geometries or welding into crossbars, and provide similar and sometimes higher resistance to pullout than the rectangular strip. This was achieved while reducing the weight per foot of reinforcement of steel required and providing cost saving benefits.
Achieving Uniform Flow Distribution In Compact Irrigation Splitter Boxes With High Flow Rates, Joshua Ryan Hogge
Achieving Uniform Flow Distribution In Compact Irrigation Splitter Boxes With High Flow Rates, Joshua Ryan Hogge
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In many irrigation systems and networks, there are multiple water users and shareholders who take their water from different locations along a single canal or pipeline. Often, irrigation splitter boxes are used to divert water to multiple shareholders from a single location. The splitter boxes, which can be small and compact, are generally installed at different locations along a piped irrigation supply line. The purpose of a splitter box is to split a specific amount of water so that each user receives their allotted portion, regardless of the flow rate in the system.
Each splitter box usually includes two compartments, …
Accumulation And Release Of Trace Inorganic Contaminants From Biofilm Matrices Produced And Challenged Under Drinking Water Distribution System Conditions, William W. Kent
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Drinking water distribution systems (DWDS) are used to transport drinking water from the place of treatment to your home. DWDS are made of many types of pipe materials and have the potential to accumulate materials such as iron and manganese oxides and biofilms that serve as reservoirs for toxic trace inorganic contaminants (TICs) such as thallium, arsenic, and lead. These materials can be stable, but changes in water quality or a physical disturbance such as road construction or water use changes may result in a TIC release, causing water quality degradation. This study used glass columns filled with glass beads …
Anaerobic Hydrogen And Methane Production From Dairy Processing Waste: Experiment And Modeling, Jianming Zhong
Anaerobic Hydrogen And Methane Production From Dairy Processing Waste: Experiment And Modeling, Jianming Zhong
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Dairy processing waste (DPW) is the waste produced from manufacturing dairy products: cheese, yogurt, ice cream, milk, butter, etc. DPW is high in chemical oxygen demand (COD) due to its lactose, fat and protein content, and therefore needs to be appropriately treated. An investigation was conducted to produce energy (hydrogen and methane) from DPW by anaerobic digestion. This project developed an effective engineering method for stable methane production from DPW without adding pH control chemicals. This study also explored the optimal operational condition for hydrogen production from DPW. We further built a mathematical model to help us monitor and predict …
Quantifying The Removal Of Trichloroethylene Via Phytoremediation At Hill Air Force Base, Utah Operational Unit 2 Using Recent And Historical Data, J. Oliver Diamond
Quantifying The Removal Of Trichloroethylene Via Phytoremediation At Hill Air Force Base, Utah Operational Unit 2 Using Recent And Historical Data, J. Oliver Diamond
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Trichloroethylene (TCE) is a carcinogenic, chlorinated volatile organic compound that was commonly used as a degreasing solvent for aircraft maintenance at many US Air Force bases. Past improper disposal of TCE has resulted in contaminated groundwater plumes surrounding many of these facilities. Phytoremediation, defined as the use of plants and their associated microorganisms to stabilize or remove contamination, has been implemented as part of a TCE groundwater cleanup effort at Travis Air Force base near Sacramento, CA and is being considered as a remediation option at other bases. Volatilization of TCE from leaves and the surface of the soil near …
Traffic Sign Management: Data Integration And Analysis Methods For Mobile Lidar And Digital Photolog Big Data, Majid Khalilikhah
Traffic Sign Management: Data Integration And Analysis Methods For Mobile Lidar And Digital Photolog Big Data, Majid Khalilikhah
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Traffic signs often convey critical information to drivers. However, traffic signs are only effective when clearly visible and legible. This study aims to determine the effects of various damage and deterioration forms on sign retroreflectivity, identify the most important factors affecting traffic sign visual condition, predict traffic sign vandalism that obstructs critical messages to drivers, and identify important environmental factors contributing to the temporary obstruction of the sign messages. To do so, two data sets are used. A sample data of over 1,700 signs was manually collected in the field, and the background retroreflectivity of each sign was measured using …
The Effects Of Meter Orientation Downstream Of A Short Radius Elbow On Electromagnetic Flow Meters, Jared C. Justensen
The Effects Of Meter Orientation Downstream Of A Short Radius Elbow On Electromagnetic Flow Meters, Jared C. Justensen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Electromagnetic flowmeters (known as magnetic flow meters) are a widely used type of flowmeter. The accuracy of magnetic flow meters are a function of several factors, not the least of which is the flow condition inside the pipe. It has been shown that disturbances in the velocity profile affects the accuracy of a magnetic flow meter (Luntta, 1998). Accordingly, manufacturers of magnetic flow meters give installation guidelines. These guidelines help prevent the user from installing the meter in a pipe configuration that is likely to cause the meter to produce inaccurate results. Although most manufacturers provide recommendations about the amount …
Developing A Method For Quantifying Nitrogen Transformation Rates Using In Situ Benthic Chambers Dosed With Isotopically Labeled Nitrate, Chelsea A. Stewardson
Developing A Method For Quantifying Nitrogen Transformation Rates Using In Situ Benthic Chambers Dosed With Isotopically Labeled Nitrate, Chelsea A. Stewardson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen, a nutrient required for biological growth, is a common water quality parameter of concern as too much nitrogen can cause a strain on aquatic environments and even death of plants and animals. One way high levels of nitrogen are introduced into aquatic systems is by anthropogenic sources such as effluent from water reclamation facilities. A method was designed to observe the fate of nitrogen and measure the rates of its transformation into different nitrogen species within a stream receiving the effluent from the Silver Creek Water Reclamation Facility in Park City, Utah.
Sealed chambers were designed and installed along …
Application Of Computational Fluid Dynamics In Flow Measurement And Meter Design, Zachary B. Sharp
Application Of Computational Fluid Dynamics In Flow Measurement And Meter Design, Zachary B. Sharp
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Flow measurement has been an important part of society for hundreds of years. For this reason there are many methods to measure flow rates both in open channel scenarios like irrigation canals and also in closed conduits like pipelines that supply water for human use. This research focused on Venturi flow meters which have been used to measure flow since the 1890’s. The object of this research was to use computational fluid dynamics and laboratory data to provide industry with applicable answers to some under researched areas in flow measurement. The areas chosen for this research include areas requested by …
The Application Of Unmanned Aerial Vehicle To Precision Agriculture: Chlorophyll, Nitrogen, And Evapotranspiration Estimation, Manal Elarab
The Application Of Unmanned Aerial Vehicle To Precision Agriculture: Chlorophyll, Nitrogen, And Evapotranspiration Estimation, Manal Elarab
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Precision agriculture (PA) is an integration of a set of technologies aiming to improve productivity and profitability while sustaining the quality of the surrounding environment. It is a process that vastly relies on high-resolution information to enable greater precision in the management of inputs to production. This dissertation explores the usage of multispectral high resolution aerial imagery acquired by an unmanned aerial systems (UAS) platform to estimate three fundamental crop parameters (plant chlorophyll, leaf nitrogen and crop water demand). The UAS acquired imagery in the visual, near infrared and thermal infrared spectra with a resolution of less than a meter …
Analyzing Irrigation District Water Productivity By Benchmarking Current Operations Using Remote Sensing And Simulation Of Alternative Water Delivery Scenarios, Jonna D. Van Opstal
Analyzing Irrigation District Water Productivity By Benchmarking Current Operations Using Remote Sensing And Simulation Of Alternative Water Delivery Scenarios, Jonna D. Van Opstal
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The competition for fresh water is vastly increasing particularly in semi-arid areas. Agricultural irrigation areas are urged to decrease their water use, being the largest consumer of fresh water in these areas. Improvements in irrigation management aim at increasing crop production whilst maintaining or decreasing water use. The analysis of water productivity at the irrigation district scale is challenging due to spatial heterogeneity between fields and temporal variability between growing seasons.
This dissertation makes use of satellite-based remote sensing imagery and an irrigation system simulation model to determine the water management at different spatial scales from field scale to the …
Anaerobic Digestion Process Stability And The Extension Of The Adm1 For Municipal Sludge Co-Digested With Bakery Waste, Morris Elya Demitry
Anaerobic Digestion Process Stability And The Extension Of The Adm1 For Municipal Sludge Co-Digested With Bakery Waste, Morris Elya Demitry
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The anaerobic digestion process is used to treat and convert waste organic matter to biogas (principally methane and carbon dioxide) through biological, chemical and physical reactions. The biogas can be used as a source of energy recovery. In order to increase the biogas production rate, two different kinds of waste (municipal wastewater treatment sludge and bakery waste) were mixed together to enhance the anaerobic process and increase the biogas production in pilot scale reactors. The process succeeded in increasing biogas production and at the same time kept the process of treatment effective when high rates of organics were fed to …
A Risk-Based Assessment Of Agricultural Water Scarcity Under Climate Change In A Semi-Arid And Snowmelt-Dominated River Basin, Hossam Moursi
A Risk-Based Assessment Of Agricultural Water Scarcity Under Climate Change In A Semi-Arid And Snowmelt-Dominated River Basin, Hossam Moursi
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Water shortage is a crucial concern in the semi-arid areas that have relatively low precipitation. Given the current situation in semi-arid areas where the water supply
already does not meet the water demand, climate change is one of the important factors that is expected to exacerbate the water shortage problem and make the situation even worse in the future. There are many indicators that prove climate change is happening, like the increasing land temperature, sea level rise and decreasing snow cover. Therefore, studying climate change impacts is a vital issue, especially its impacts on water resources systems.
In this research, …
Laboratory Modeling Of Piping Initiation Behavior Through Constricted Outlet, Ibrahim Ahmed Abdelmotelb Ibrahim
Laboratory Modeling Of Piping Initiation Behavior Through Constricted Outlet, Ibrahim Ahmed Abdelmotelb Ibrahim
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Backward erosion piping is a type of internal erosion. It occurs beneath water structures as a result of seepage force. It needs two conditions to take place; 1) sufficient hydraulic head to drive the seepage force, and 2) cohesive layer overlies the sand layer and this will lead to concentration of flow. Many researches were done in the past in an attempt to predict the critical gradient. But it was just taking into account the buoyant unit weight which found in recent research that piping can occur at much lower values than was predicted. And other researches were too conservative …
Partially Closed Valve Effects On Electromagnetic Flow Meter Accuracy, Jordan Clark Jarrett
Partially Closed Valve Effects On Electromagnetic Flow Meter Accuracy, Jordan Clark Jarrett
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
As the need to manage water resources increases, the ability to accurately measure use becomes crucial. In industry, measurement inaccuracies can cost either the
supplier or consumer large amounts of money or even result in a depleted resource. Generally, flow meters need a flow profile to be fully developed so to optimize
measurement accuracy.
In order to produce accurate measurements, most flow meters require a straight section of pipe immediately upstream of the meter. The straight pipe helps to develop the flow profile and produces flow conditions that are as ideal as possible. In many field installations, space restrictions lead …
An Analysis Of Airborne Data Collection Methods For Updating Highway Feature Inventory, Yi He
An Analysis Of Airborne Data Collection Methods For Updating Highway Feature Inventory, Yi He
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Highway inventory plays an important role in highway management. Governments and agencies have been employing different kinds of methodologies for highway inventory. Existing methodologies include field inventory, photo/video log, integrated global positioning system (GPS)/ global information system (GIS) mapping, aerial/satellite photography, terrestrial light detection and ranging (LiDAR), mobile LiDAR, and airborne LiDAR. Each has advantages and disadvantages as well as limitations in collecting road inventory data. This paper mainly focused on the application of airborne data collection method.
Four highway sections in Utah were mapped in this experiment: one section on Interstate 84 (I-84), two sections on Interstate 15 (I-15 …
Optimizing Sustainable Integrated Use Of Groundwater, Surface Water And Reclaimed Water For The Competing Demands Of Agricultural Net Return And Urban Population, Silvia Anastasia Landa
Optimizing Sustainable Integrated Use Of Groundwater, Surface Water And Reclaimed Water For The Competing Demands Of Agricultural Net Return And Urban Population, Silvia Anastasia Landa
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The world population is growing rapidly. In developing countries, the growing population is mostly in urban areas. A bigger population requires more food, and more food requires more water. The water needed for food and people comes from the same sources: surface water (rivers, lakes, etc.) and groundwater (aquifers). Thus, there is a competing water demand between people and agriculture in urban areas.
In this research, we use computer software to make a model of the hydrologic system that focuses on surface water and groundwater. To make the model, we use data from real aquifers and streams in order to …
The Effects Of Upstream Straight Pipe Length On Magnetic Flow Meter Accuracy, Bradley C. Clawson
The Effects Of Upstream Straight Pipe Length On Magnetic Flow Meter Accuracy, Bradley C. Clawson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In closed conduit water systems, being able to accurately measure flow is absolutely essential. For many meter designs, including electromagnetic induction meters (also known as magnetic flow meters), the greatest accuracy is achieved when the device is calibrated correctly. Optimal meter accuracy often depends on the flow conditions associated with the upstream geometry in the pipe system. Manufacturers typically give standards for the length of straight pipe required upstream of the meter. These standards vary, however, and do not address every possible configuration that may be installed upstream of the straight pipe requirement.
An investigation on the effects of the …
Live-Load Test And Finite-Element Model Analysis Of A Steel Girder Bridge, Jake L. Morrill
Live-Load Test And Finite-Element Model Analysis Of A Steel Girder Bridge, Jake L. Morrill
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Utah Transportation Center in conjunction with the Mountain Plains Consortium sponsored a study to investigate the performance, and condition of a steel, twin, I-girder bridge. The bridge is located on the Idaho-Oregon border near Payette, Idaho, and was designed to carry traffic over the Snake River.
Bridge Diagnostics Inc. was contracted by the Idaho Transportation Department to perform a live-load test on the bridge. This testing included the placement of 62 gauges that measured the response of the bridge as heavy trucks were driven across it.
A 3-D finite-element model of the bridge was generated and compared to the …
Agricultural Water Management In The Sevier River Basin, Utah: A Multidisciplinary Approach, Daeha Kim
Agricultural Water Management In The Sevier River Basin, Utah: A Multidisciplinary Approach, Daeha Kim
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Sevier River Basin situated in south central Utah is characterized by its semiarid climate, snowmelt-driven runoff, and high dependency on agricultural economy. High evapotranspiration and low precipitation make agricultural production challenging, but naturally stored water in the snowpack in the mountains alleviates water stresses during high water demand seasons. The snowmelt-driven river flow along the main channel is highly exploited for irrigation for farms near the Sevier River. Reservoir operations and river diversions result in heavily regulated flows from the upper to the lower basins. The return flows of over-irrigated water in the upper basin increase salinity of surface …
Innovative And Efficient Simulation-Optimization Tools For Successful Groundwater Management And Conflict Resolution, Bassel Timani
Innovative And Efficient Simulation-Optimization Tools For Successful Groundwater Management And Conflict Resolution, Bassel Timani
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Simulation-Optimization (S-O) models are exemplary for strategic groundwater management planning. The two components of an S-O model serve different purposes. The simulation component models the aquifer and computes state variables resulting from stimuli such as extraction or diversion while the optimizor computes an optimal set of stimuli that maximize an objective function and satisfy a set of constraints. With the increased use of S-O model for larger and more complex real-world study areas, the use of fast and efficient S-O models has risen. Response matrix methods (RMMs) are usually used as substitute simulators within an S-O to solve the posed …
Transportation Economics And Energy, Ali Soltani Sobh
Transportation Economics And Energy, Ali Soltani Sobh
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Transportation is one of the major energy consuming sectors in the United States. The continued growth in fuel consumption not only increases dependency on foreign oil but also causes environmental issues due to the emissions of greenhouse gas (GHG). High gasoline consumption in the US transportation sector not only raises concerns regarding national energy security, but also poses many questions regarding the resulting environmental impacts of greenhouse gases emissions. Improvement in automobile fuel economy, increase the use of natural gas vehicles and electric vehicles have been proven to be as the policies in controlling oil demand and GHG emissions in …
Laboratory Study On The Effects Of Exit Face Inclination Of Critical Gradients, Richard Allen Keizer Jr.
Laboratory Study On The Effects Of Exit Face Inclination Of Critical Gradients, Richard Allen Keizer Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The objective of this research is to help better understand the effects of exit face inclinations on critical gradients. This will lead to more practical ways to predict critical hydraulic gradients and slope stability using soil properties and exit face conditions. Current geotechnical engineering does not consider these factors because they are not thoroughly understood. Despite the attempts to better predict critical gradients, methods developed over 70 years ago to model the heave mechanism are used to model failure mechanisms such as backward erosion (or piping). This critical hydraulic gradient is only calculated by means of the buoyant unit weight …
High Resolution Multi-Spectral Imagery And Learning Machines In Precision Irrigation Water Management, Leila Hassan-Esfahani
High Resolution Multi-Spectral Imagery And Learning Machines In Precision Irrigation Water Management, Leila Hassan-Esfahani
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The goals of preserving scarce water resources, cultivating more lands, and saving on irrigation water bills have directed the attention of water resources managers toward the concepts of precision agriculture and, in particular, to precision irrigation. The purpose of precision irrigation is to increase irrigation efficiency to avoid crop water stress, avoid yield reduction due to under-irrigation and leaching of nutrients, runoff, and reduce soil erosion due to over-irrigation. In this study, irrigation efficiency has been defined in terms of irrigation uniformity and the response of the crop to irrigation. Crop water demand, soil moisture, evapotranspiration rate, and potential water …
The Fate Of Pharmaceuticals And Personal Care Products In Conventional And Engineered On-Site Wastewater Drain Fields, James Beardall
The Fate Of Pharmaceuticals And Personal Care Products In Conventional And Engineered On-Site Wastewater Drain Fields, James Beardall
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Utah State University Division of Environmental Engineering student, under the direction of Ms. Judith L. Sims, has investigated the fate of six pharmaceuticals and personal care products (PPCPs) in conventional and engineered on-site wastewater drain fields. The presence of PPCPs in the environment, especially in aquatic environments, has raised awareness to the effects of PPCPs on aquatic life and the fate of these PPCPs, and has caused regulators to become more involved in setting requirements for the removal of PPCPs from wastewater.
This research investigated the fate of caffeine, acetaminophen, carbamazepine, sulfamethoxazole, progesterone, and fluoxetine in laboratory scaled columns that …
Testing Of Rainflow Histograms Of Strain For Implementation As A Bridge Weigh-In-Motion Technique, Nephi R. Johnson
Testing Of Rainflow Histograms Of Strain For Implementation As A Bridge Weigh-In-Motion Technique, Nephi R. Johnson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The highways and bridges that make up the nation’s infrastructure are becoming older and need replacement or maintenance. In order to determine the best use of funds, bridges are being monitored and studied. This paper was part of a long term study with the goal of monitoring multiple bridges for several years in order to develop an extensive network of bridge information. This particular study was on a bridge in Utah that was instrumented with permanent measurement and monitoring devices. Monitoring of bridges provides information on how the temperature and weather cause the bridge to move, change and age. It …
Systems Optimization Models To Improve Water Management And Environmental Decision Making, Omar Alminagorta Cabezas
Systems Optimization Models To Improve Water Management And Environmental Decision Making, Omar Alminagorta Cabezas
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The degradation of water quality and wetlands is one of the most challenging environmental problems around the world. In spite of the magnitude of these environmental problems, few efforts identify how scarce resources (e.g., water, budget) can be more efficiently used to solve these problems. This dissertation presents a set of tools to help solve environmental problems related to excess phosphorus levels in water bodies and wetland degradation caused by water shortages and invasive vegetation. These tools are presented in three studies. The first study presents a simple optimization model that identifies the cost-effective combination of management practices to reduce …
Arsenic Release From Dechlorination Remediation Processes Of Biostimulation And Bioaugmentation, Suzy Smith
Arsenic Release From Dechlorination Remediation Processes Of Biostimulation And Bioaugmentation, Suzy Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Arsenic (As), a known carcinogen, is a groundwater contaminant in many parts of the world. Arsenic contamination is enhanced through carbon addition, such as biostimulation, a remediation process, which has been used to remove trichloroethylene (TCE) from sediment and groundwater. Two studies were designed to evaluate the effect of different carbon sources on the removal of TCE through dechlorination and on As solubilization and mobilization in response to carbon addition.
The first set of columns (15.2 cm diameter, 183 cm long) used whey, Newman Zone® standard surfactant emulsified oil, Newman Zone® nonionic surfactant emulsified oil, and no carbon controls as …
Continuous Unbonded Post-Tensioned Members: Quantifying Strand Stress Increase, Philip D. Six
Continuous Unbonded Post-Tensioned Members: Quantifying Strand Stress Increase, Philip D. Six
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Unbonded post-tensioning tendons are an efficient and cost effective method of reinforcing concrete floor slabs, slabs-on-grade, parking garages, and bridge structures. However, the behavior of these structures is not well understood. There is concern that due to the lack of a significant amount of reliable research data on specimens reinforced in this manner, the commonly used design methods tend to significantly under-predict the strength. Four large, scaled, floor slab sections were constructed and destructively tested with the intent of more accurately understanding the strength of specimens reinforced with this method. Four test specimens represent a significant percentage of the current …
Catalytic Pyrolysis Of Olive Mill Wastewater Sludge, Hamza Abdellaoui
Catalytic Pyrolysis Of Olive Mill Wastewater Sludge, Hamza Abdellaoui
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
From 2008 to 2013, an average of 2,821.4 kilotons/year of olive oil were produced around the world. The waste product of the olive mill industry consists of solid residue (pomace) and wastewater (OMW). Annually, around 30 million m3 of OMW are produced in the Mediterranean area, 700,000 m3 year−1 in Tunisia alone. OMW is an aqueous effluent characterized by an offensive smell and high organic matter content, including high molecular weight phenolic compounds and long-chain fatty acids. These compounds are highly toxic to micro-organisms and plants, which makes the OMW a serious threat to the environment if …