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Full-Text Articles in Engineering

Field Calibration Of Flow Over Tilting Weirs In Canals, Joseph E. Pugh, Timothy K. Gates, S. Karan Venayagamoorthy, Caner Kutlu Aug 2026

Field Calibration Of Flow Over Tilting Weirs In Canals, Joseph E. Pugh, Timothy K. Gates, S. Karan Venayagamoorthy, Caner Kutlu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tilting weirs are widely used to regulate water levels in open channel irrigation systems and can also provide flow measurement capability that helps optimize irrigation efficiency and ensure equitable water distribution. This case study demonstrates adaptation of lab-based tilting weir ratings to field settings, where flow behavior is more complex. We compile and analyze an extensive data set derived from independent studies of five structures within three canal systems, featuring both lined and unlined channels with discharge ranging from 0.35 to 15 m3/s (12 to 530 ft3/s). Results indicate that lab-based rating equations can be calibrated to account for site-specific …


Five-State Seismic Damage Classification Of Steel-Girder Bridges On Soft Soil Using Directional Intensity Measures And Multi-Parameter Damage Indices, Ibrahim Alomari, Woubishet Zewdu Taffese, Mohammad Hossein Afsharmovahed, Genda Chen Aug 2026

Five-State Seismic Damage Classification Of Steel-Girder Bridges On Soft Soil Using Directional Intensity Measures And Multi-Parameter Damage Indices, Ibrahim Alomari, Woubishet Zewdu Taffese, Mohammad Hossein Afsharmovahed, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Rapid yet accurate post-earthquake damage assessment of highway bridges is essential to ensure transportation network resilience. Traditional inspection, fragility analysis, and finite element modeling are time-consuming or inaccurate for real-time decision-making. This study compares ten machine-learning classifiers for the seismic damage states of highway steel-girder bridges that incorporate directional intensity measures to represent the variance of ground motions. Based on the nonlinear time-history analyses of two Missouri bridges, one Michigan bridge, and one Wisconsin bridge, multi-parameter structural damage indices were proposed and mapped to five damage states from none to collapse. Among ten supervised algorithms studied, the artificial neural network …


Water Use And Yield Of Subsurface Drip-Irrigated Forage Crops In Northern Utah, Nishchal Tamang Aug 2026

Water Use And Yield Of Subsurface Drip-Irrigated Forage Crops In Northern Utah, Nishchal Tamang

All Graduate Reports and Creative Projects, Fall 2023 to Present

Growing water scarcity in the Intermountain West has increased interest in improving water use efficiency. Subsurface drip irrigation (SDI) has the potential to reduce evapotranspiration (ET), evaporative losses, surface runoff, and deep percolation. SDI adoption in Utah forage crops is limited, and region-specific information on forage crop water use under SDI is lacking. This study compared ET, yield, and productivity of forage crops between SDI and conventional irrigation methods in northern Utah.

The study was conducted on production fields. Applied irrigation, precipitation, and crop yield were directly measured, while deep percolation was estimated using numerical unsaturated flow modeling. Surface runoff …


A Technoeconomic And Lifecycle Analysis Of Catalytic Non-Thermal Plasma Steam Methane Reforming For Renewable Hydrogen Production, Gustav M. King Aug 2026

A Technoeconomic And Lifecycle Analysis Of Catalytic Non-Thermal Plasma Steam Methane Reforming For Renewable Hydrogen Production, Gustav M. King

Master's Theses

When produced with sufficiently low life-cycle emissions, hydrogen may support low-carbon, dispatchable electricity generation to realize statewide renewable energy regulatory objectives. This thesis develops a screening-level electrothermochemical process model of catalytic non-thermal plasma steam methane reforming (CNTP-SMR) and integrates it with techno-economic and life-cycle assessments. Biogas and natural gas fed CNTP-SMR scenarios are compared with conventional steam methane reforming to evaluate hydrogen production cost, global warming potential, and the effects of key operating parameters. Under the baseline assumptions, CNTP-SMR generated hydrogen at a higher levelized cost (baseline of $3.86/kg H2 and a range of $3.68 to $4.11) when compared …


Effect Of Rheology Modification On Fiber Orientation And Dispersion In 3d-Printed Ultra-High-Performance Concrete, Haodao Li, Alfred Addai-Nimoh, Seongho Han, Kamal H. Khayat Aug 2026

Effect Of Rheology Modification On Fiber Orientation And Dispersion In 3d-Printed Ultra-High-Performance Concrete, Haodao Li, Alfred Addai-Nimoh, Seongho Han, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The extrusion process in 3D concrete printing (3DCP) facilitates horizontal alignment of steel fibers along the printing direction, thus enhancing the load-bearing capacity of printed elements. However, such shear-induced fiber alignment is highly sensitive to rheological properties. This study investigates how variations in dynamic yield stress (τd) and plastic viscosity (μ), influence the extrudability, fiber orientation and dispersion, and anisotropic mechanical behavior of ultra-high-performance concrete (UHPC). Five viscosity-modifying agent (VMA) types were incorporated at two content levels to modify the rheology of printable UHPC. Results showed that moderate VMA additions improved printability, whereas excessive contents markedly increased τd and μ; …


Barrier-Drainage Performance Of A Wicking Geotextile In Controlling Capillary Rise In Silt: Experimental Evaluation, Dahao Zou, Yipeng Guo, Jiejin Chen, Yafeng Li, Xiong Zhang, Yongjie Zhang, Luqiang Ding Aug 2026

Barrier-Drainage Performance Of A Wicking Geotextile In Controlling Capillary Rise In Silt: Experimental Evaluation, Dahao Zou, Yipeng Guo, Jiejin Chen, Yafeng Li, Xiong Zhang, Yongjie Zhang, Luqiang Ding

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Capillary rise in silt significantly degrades its strength and durability, yet the hydraulic mechanisms governing moisture control using wicking geotextile in silt remain insufficiently understood. This study investigates the barrier-drainage performance of a wicking geotextile in silt through one-dimensional column experiments, supported by preliminary trials. Three configurations were examined: a control specimen without geotextile (CS), an embedded configuration (ES), and a surface-exposed configuration (SES). Volumetric moisture content and matric suction were monitored, capillary responses at the soil-geotextile interface and water storage behavior were evaluated. The results show that the wicking geotextile initially acts as a temporary capillary barrier due to …


City Farm Slo - Market Stand Modernization, Juan Diaz Aug 2026

City Farm Slo - Market Stand Modernization, Juan Diaz

Construction Management

This paper analyzes the design, planning, and buildout of a custom multi-level stand, farm signage, and supporting equipment for the non-profit organization City Farm SLO. The overall goal of the project was to provide the farm with a modernized and functional market space. The project first addressed any owner design requirements, the approval of materials lists, and the assessment of existing conditions. The pre-construction consisted of developed drawings, materials lists, cost estimates, and a project schedule. Aside from setting up requirements, the owner provided specific milestones to be achieved during the construction phase of the project. A major risk found …


0905: American Car And Foundry (Acf) Collection, 1916-2019, Marshall University Special Collections Aug 2026

0905: American Car And Foundry (Acf) Collection, 1916-2019, Marshall University Special Collections

Guides to Manuscript Collections

The collection includes only documents that were found in the plant in 2021. These primarily consist of files on capital projects from the 1970s through the 1990s. Also included are notebooks with job descriptions and classifications; ledger books containing maintenance purchase orders; quality assurance manuals; visitors register books from 1973-2019; drawings of plant machinery and operations; slides and photographs; and miscellaneous materials.

The forerunner to ACF was Ensign Manufacturing Company, founded in 1871 at Huntington, West Virginia, by William H. Barnum and Ely Ensign, both from prominent families of Lime Rock, Connecticut. It was chartered (incorporated) on November 1, 1872, …


The Influence Of Rainfall And Land Cover Change On Streamflow Variability In Eastern Florida Watersheds, Brynn Romberger Aug 2026

The Influence Of Rainfall And Land Cover Change On Streamflow Variability In Eastern Florida Watersheds, Brynn Romberger

Theses and Dissertations

Streamflow in Florida watersheds is influenced by both land cover change and rainfall variability, but separating their contributions is difficult because both have changed over recent decades. This study evaluated rainfall trends and land cover change to determine which better explains flood and drought threshold exceedance across 27 USGS streamflow gauges within the St. Johns River Water Management District (SJRWMD) from 1985 to 2025. Streamflow was characterized using change-point, trend, and variability analyses with a six-threshold exceedance framework. Land cover was quantified using the National Land Cover Database (NLCD), rainfall characteristics were derived from the Analysis of Records for Calibration …


Building Services Engineering July/August 2026 Aug 2026

Building Services Engineering July/August 2026

Building Services Engineering

This issue of Building Services Engineering features heat pumps, propane usage, solar power, and ventilation for indoor air quality. Features include district heating, HVACR optimisation, lift retrofitting, EU water policy, and an interview with WiBSE Ireland Chair Heather Holt.


Evaluation Of Dredged Sediments As A Partial Replacement For Fine Aggregate In Mortar And Concrete, Ashish Gautam Aug 2026

Evaluation Of Dredged Sediments As A Partial Replacement For Fine Aggregate In Mortar And Concrete, Ashish Gautam

Graduate Theses and Dissertations (2019 - present)

The feasibility of using dredged sediment from the Mobile River as a partial replacement for fine aggregate in mortar and concrete was investigated through a series of laboratory characterization and performance evaluation. Three dredged sediment samples (A, B and C) were initially examined, and Sample A was selected for further evaluation due to its closer resemblance to natural fine aggregate. This sample exhibited lower moisture content, higher sand equivalent values, higher specific gravity, and lower absorption. Mortar mixtures with 0, 10, 20, 30, 50, 75 and 100% dredged sediment replacement showed decreasing workability as the replacement level increased. The 20% …


Human-Centered Electric Vehicle Adoption Framework For Smart Mobility: Modeling Perceived Range And Charging Anxiety As A Psychological Barrier, Fatemeh Nazari, Abolfazl (Kouros) Mohammadian, Thomas Stephens Aug 2026

Human-Centered Electric Vehicle Adoption Framework For Smart Mobility: Modeling Perceived Range And Charging Anxiety As A Psychological Barrier, Fatemeh Nazari, Abolfazl (Kouros) Mohammadian, Thomas Stephens

Civil Engineering Faculty Publications

Electric vehicles (EVs) offer a transformative pathway toward reducing the environmental, economic, and health-related externalities of internal combustion engine vehicles in urban settings. Despite substantial advances in battery technology, charging infrastructure expansion, and supportive policy incentives, EV penetration remains limited which poses challenges for smart and sustainable mobility planning. A critical yet insufficiently modeled barrier to adoption lies in the psychological perceptions surrounding electric driving range and charging reliability, which is commonly framed as “range anxiety,” but more broadly reflecting perceived range and charging anxiety. To address this gap, this study introduces a latent psychological construct capturing individuals’ perceived range …


Strain Monitoring And Site Characterization At Birds Landing From Transmission Tower Implosions Recorded Using Das And Nodal Stations, Prajwal Panthi Aug 2026

Strain Monitoring And Site Characterization At Birds Landing From Transmission Tower Implosions Recorded Using Das And Nodal Stations, Prajwal Panthi

All Graduate Theses and Dissertations, Fall 2023 to Present

When two old electrical transmission towers in the Sacramento River Delta in California were demolished by Pacific Gas and Electric Company, Utah State University saw an opportunity hiding inside the demolition. Because one of the towers stood close to the Sacramento River and its protective levee, they used the controlled collapse not only to monitor strains in the levee and surrounding ground, but also to learn what lied beneath the ground surface.

To capture this event, the researchers buried a 1.4-kilometer fiber optic cable along the ground and connected it to a system called Distributed Acoustic Sensing (DAS), which can …


A Multi-Label Computer Vision-Based Approach For Condition Assessment Of Traffic Signs: Database Compilation, Model Training, And Evaluation, Shailaja Ratna Pandey Aug 2026

A Multi-Label Computer Vision-Based Approach For Condition Assessment Of Traffic Signs: Database Compilation, Model Training, And Evaluation, Shailaja Ratna Pandey

All Graduate Theses and Dissertations, Fall 2023 to Present

Traffic signs help drivers and pedestrians to understand roadway rules, warnings, and directions, which determine how road users should behave. When signs fade or delaminate, they become harder to read and interpret, which creates increased safety hazards. Transportation agencies usually deploy engineers to the field to inspect signs because they need to evaluate and document the sign’s condition based on established standards and engineering judgment. This process requires substantial time and cost and becomes challenging to apply across large highway networks.

This study evaluated two computer vision (CV) models for automated traffic sign condition assessment using highway images collected across …


The Role Of Roughness And Geometry In 2d Depth-Averaged Models: A Comparative Study Using Laboratory Flume Experiments, Adrienne Luymes Mckell Aug 2026

The Role Of Roughness And Geometry In 2d Depth-Averaged Models: A Comparative Study Using Laboratory Flume Experiments, Adrienne Luymes Mckell

All Graduate Theses and Dissertations, Fall 2023 to Present

Hydraulic models are commonly used to predict how water moves through rivers and streams, helping engineers manage flood risk and design infrastructure such as bridges, culverts, and restoration projects. One challenge in these models is representing the effects of riverbed roughness, including features such as rocks, vegetation, and other obstacles that slow water flow.

This study investigated whether it is better to represent these roughness features in detail or to simplify them while still accounting for their effects. Laboratory measurements from a controlled channel experiment were used to create two computer models: one that included the detailed shape of the …


Evaluating Data Management Practices And Ontology Development For Transportation Safety Assets, Brig Dean Adams Aug 2026

Evaluating Data Management Practices And Ontology Development For Transportation Safety Assets, Brig Dean Adams

All Graduate Theses and Dissertations, Fall 2023 to Present

Data has begun to permeate transportation agencies, with every process, asset, and event generating a great volume of data. This data helps engineers and decision makers determine maintenance schedules, devise infrastructure investment strategies, improve safety, and plan for future needs. Due to the size of transportation agencies and the diversity of the data they collect, their data is often stored in different systems, managed by different groups, and described using inconsistent terminology. These challenges make it difficult to locate information, combine data from multiple sources, and confidently use data to support important decisions.

This research examined how transportation safety asset …


Comparison Of Forces Generated By An Impinging Water Jet Using Numerical And Physical Experimentation, Spencer R. Young Aug 2026

Comparison Of Forces Generated By An Impinging Water Jet Using Numerical And Physical Experimentation, Spencer R. Young

All Graduate Theses and Dissertations, Fall 2023 to Present

When water is released from hydraulic structures such as dams water jets are formed and land on the downstream surfaces. When these jets land there is high potential for erosion or scour. Scour has the potential to compromise the structure and cause the uncontrolled release of water that can endanger downstream communities and infrastructure.

Engineers use tools including computational fluid dynamics (CFD) to inform their designs to mitigate the risk of scour. This study compares how well CFD is able to model the forces created by a water jet by comparing the results to laboratory collected physical data. To make …


Experimental And Numerical Investigation Of Flow Coefficients In Three-Way, T-Port, Ball Valve, Tyler A. Mindrum Aug 2026

Experimental And Numerical Investigation Of Flow Coefficients In Three-Way, T-Port, Ball Valve, Tyler A. Mindrum

All Graduate Theses and Dissertations, Fall 2023 to Present

Many systems that move fluids, like water distribution networks and heating, ventilation, and air conditioning (HVAC) systems, rely on valves to control flow. This study evaluates a three-way valve, which can direct flow in multiple directions, but has not been extensively researched. Testing included physical data collection and computer simulations to compare how the valves behaved under different valve openings and flow conditions. The results showed that computer simulations can predict the general flow behavior of three-way valves, but that physical testing is still important, especially for valves with complex internal geometries.


A Laboratory Investigation Of Energy Dissipators At Embankment Dams, Nathan L. Young Aug 2026

A Laboratory Investigation Of Energy Dissipators At Embankment Dams, Nathan L. Young

All Graduate Theses and Dissertations, Fall 2023 to Present

Dams play a critical role in protecting communities from flooding and providing reliable water supplies. When large amounts of water pass through a dam’s spillway during floods, the discharge can travel at high speeds and carry potentially destructive kinetic energy that can damage the dam or erode downstream channels if that energy is not properly controlled. To reduce this risk, engineers commonly use hydraulic structures called energy dissipators that slow spillway discharge and safely release it downstream.

Commonly used energy dissipators at embankment dams include stilling basins that rely on a hydraulic jump – a sudden rise in water depth …


Clogging Behaviour And Management In Two Full-Scale Infiltration Schemes: A Treated Wastewater Basin And A Surface-Water Weir In Australia, John Awad, Declan Page, Joanne Vanderzalm, Geoffrey J. Puzon, Jason Wylie, Falko Mathes, Debbie Reed, Michael Bartkow, Mehdi Khiadani, Karen Barry, Peter Dillon Aug 2026

Clogging Behaviour And Management In Two Full-Scale Infiltration Schemes: A Treated Wastewater Basin And A Surface-Water Weir In Australia, John Awad, Declan Page, Joanne Vanderzalm, Geoffrey J. Puzon, Jason Wylie, Falko Mathes, Debbie Reed, Michael Bartkow, Mehdi Khiadani, Karen Barry, Peter Dillon

Research outputs 2022 to 2026

Managed Aquifer Recharge (MAR) schemes are increasingly used to enhance water security, yet infiltration schemes are susceptible to clogging which consequently reduces operational efficiency. This study examines two full-scale Australian case studies: Jurien Bay (JB, Western Australia) and Lockyer Valley (LV, Queensland), representing treated wastewater (TWW) and surface water recharge, respectively. Recharge water at JB exhibited high clogging potential in relation to literature values proposed to manage clogging: total suspended solids (TSS) ranged from 100 to 176 mg/L (target ≤2 mg/L), turbidity 70–100 NTU (target ≤3 NTU), and total nitrogen (TN) 5–16 mg/L (target ≤10 mg/L). LV showed lower clogging …


Multistage Integrated Systems For Wastewater Treatment And Resource Recovery: A Systematic Process Design Framework, Mahsa Golmohammadi, Ensiyeh Taheri, Ratish Ramyad Permala, Sebastien Allard, Mehdi Khiadani, Amir Razmjou Aug 2026

Multistage Integrated Systems For Wastewater Treatment And Resource Recovery: A Systematic Process Design Framework, Mahsa Golmohammadi, Ensiyeh Taheri, Ratish Ramyad Permala, Sebastien Allard, Mehdi Khiadani, Amir Razmjou

Research outputs 2022 to 2026

The wastewater treatment paradigm is shifting from pollutant removal toward integrated systems that simultaneously achieve contaminant treatment and resource recovery. Despite extensive literature on individual technologies, systematic frameworks for designing multistage integrated wastewater treatment and resource recovery systems remain notably absent. This review addresses this gap by developing a comprehensive decision framework that guides designers from influent characterization through technology selection across pretreatment, main process, and post-treatment stages. The framework accommodates diverse integration strategies, ranging from fully unified treatment processes to stage-specific configurations where each treatment stage employs technologies tailored to its designated function. Rather than optimizing for a single …


Machine Learning For Predictive Energy And Emissions Modeling Of Vehicles And Power Grids In The United States, S M Tanvir Faysal Alam Chowdhoury Aug 2026

Machine Learning For Predictive Energy And Emissions Modeling Of Vehicles And Power Grids In The United States, S M Tanvir Faysal Alam Chowdhoury

Dissertations

The environmental benefits of electric vehicle (EV) adoption depend on more than replacing internal combustion engine vehicles with electric powertrains. EV adoption reshapes electricity demand, interacts with regional generation mixes, and influences travel behavior and congestion, creating a coupled transportation-energy system in which vehicle and power-plant emissions must be evaluated together. This dissertation develops machine-learning frameworks for predicting energy consumption and emissions from vehicles and power grids under rising EV adoption. The first component forecasts grid emissions from EV charging. Using simulation data from NREL's Cambium database, a Prophet-based time-series framework predicts carbon dioxide, nitrous oxide, and methane emission rates …


Synthesis And Characterization Of Carbon Quantum Dots And Gold Nanoparticles For Norovirus Biosensing Applications In Water Systems, Breanne Evans Aug 2026

Synthesis And Characterization Of Carbon Quantum Dots And Gold Nanoparticles For Norovirus Biosensing Applications In Water Systems, Breanne Evans

Master's Theses

Rapid, reliable detection of viral pathogens remains a significant challenge across water-treatment and environmental monitoring systems, including drinking-water, wastewater, water reuse, and environmental surveillance applications. Waterborne viral contamination can pose substantial public-health risks, making early detection essential for protecting water quality and responding quickly to treatment failures or contamination events. Direct potable reuse (DPR) is one particularly demanding example because it requires continuous verification of treatment performance and the broader need for rapid virus monitoring extends across many water-treatment and environmental surveillance applications. Norovirus is a priority target because of its widespread occurrence in wastewater, environmental persistence, and exceptionally low …


Sustainable Organic Materials Used In The Construction Sector, Michael P. Wistuba, Di Wang, Chiara Riccardi, Libo Yan, Zhanping You, Lily D. Poulikakos, Ana Jiménez Del Barco Carrión Jul 2026

Sustainable Organic Materials Used In The Construction Sector, Michael P. Wistuba, Di Wang, Chiara Riccardi, Libo Yan, Zhanping You, Lily D. Poulikakos, Ana Jiménez Del Barco Carrión

Michigan Tech Publications

No abstract provided.


Analysis Of Flood Modeling For The Replication Of An Extreme Rainfall Event In South Florida, Lusnel Fritznel Ferdinand Jul 2026

Analysis Of Flood Modeling For The Replication Of An Extreme Rainfall Event In South Florida, Lusnel Fritznel Ferdinand

Electronic Theses and Dissertations

Flooding is the most common natural disaster in the United States, and trends show an increase in flood risk for the foreseeable future. Florida averages 45 flood disasters per year, at an annual cost of $86 million. Communities in Florida are susceptible to a variety of flood-inducing sources, including tropical cyclones, extreme rainfall, and rising sea levels, which can impact the tourism industry and the economic well-being of residents. The first objective of the thesis was to use flood modeling to replicate the extreme rainfall event that caused heavy flooding in Broward County, Florida, from April 12-13, 2023. A commercial …


Comparative Performance Evaluation Of A Gpu-Accelerated Watershed Model For Flood Inundation Mapping, Maliha Ali Jul 2026

Comparative Performance Evaluation Of A Gpu-Accelerated Watershed Model For Flood Inundation Mapping, Maliha Ali

Electronic Theses and Dissertations

This study evaluates PyWMP (Python-based Watershed Modeling and Planning), which is a flood modeling framework developed by the Center for Water Resiliency and Risk Reduction (CWR3) at Florida Atlantic University (FAU). The framework includes a 2D Rain-on-Mesh (ROM) solver, which is an explicit finite-volume shallow-water equation model. PyWMP is compared against HEC-RAS 2D and Flood Modeller for their rain-on-grid capabilities for watershed-scale flood inundation mapping under three design storm scenarios. The performance of PyWMP was evaluated using both quantitative and spatial metrics. Mean absolute error values showed that the average depth difference between each model is under 1 foot. Percent …


Integrated Construction Uncertainty Quantification Framework Icuqf, Felix Delmonte Jul 2026

Integrated Construction Uncertainty Quantification Framework Icuqf, Felix Delmonte

Mechanical and Civil Engineering Faculty Publications

This study develops ICUQF, an integrated uncertainty framework for digitally instrumented construction megaprojects that unite probabilistic simulation, fuzzy reasoning, Bayesian networks, AI-driven anomaly detection, BIM-linked digital twins, and organizational learning into a single operational architecture. The framework classifies uncertainty into aleatory variability, epistemic gaps, data-centric and model-centric risks, and cognitive or cultural sources, mapping each class to computational treatments such as Monte Carlo engines for stochastic variability, fuzzy intervals and p-boxes for imprecise expert judgments, and hierarchical Bayesian models for coherent evidence aggregation and online updating. ICUQF specifies data pipelines that connect IoT sensing, edge processing, cloud storage, and Common …


Effect Of Geothermal Conditions On Silica Flour Modified Wellbore Cement, Travis Benjamin Broadhurst Jul 2026

Effect Of Geothermal Conditions On Silica Flour Modified Wellbore Cement, Travis Benjamin Broadhurst

Civil Engineering ETDs

Considerable work has been conducted on modified wellbore cements, but a knowledge gap exists in the effects of downhole conditions on cement, especially tensile strength. In this study, a pressure vessel simulates representative downhole conditions (2000C, 1.5 MPa) with a reference solution for geothermal brine and naturally occurring geothermal gases. Samples are removed after 28-days for unconfined compressive strength testing, Brazilian tensile strength testing, elastic moduli measurement, and chemical analyses by X-ray diffraction and electron microprobe. Aqueous chemical analysis suggests multiple active reactions between the geothermal fluid and cement that are exacerbated by higher temperatures, but do not …


Mechanisms Of Advanced And Energy Efficient Wastewater Treatment Technologies, Derek Belka Jul 2026

Mechanisms Of Advanced And Energy Efficient Wastewater Treatment Technologies, Derek Belka

Civil Engineering ETDs

This dissertation combines meta-omics, microbial ecology, and hydrodynamic analysis to explore mechanisms of enhanced biological phosphorus removal (EBPR) and aerobic granular sludge (AGS) in municipal wastewater treatment. Metagenomic and functional gene profiling of a laboratory sequencing batch reactor fed with amino acids and proteins, and with a low abundance of known polyphosphate-accumulating organisms (PAOs), revealed abundant Herpetosiphonaceae and Dermatophilaceae families possessed key PAO metabolic traits, including phosphate scavenging, anaerobic carbon pathways, and ppk2 gene variants aligned with established PAOs. These findings suggest amino acid-driven EBPR can occur via previously unrecognized taxa, challenging current engineering assumptions and highlighting the need for …


Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby Jul 2026

Wildfire Impacts On Fluvial Hydrology From Watershed To National Scales, Paige G. Tunby

Civil Engineering ETDs

Wildfires alter the water quantity and quality in downstream river networks. Fires promote biodiversity, maintain habitat, and provide many ecosystem services in a fire-adapted landscape. However, changes in the natural fire regimes can alter ecosystem function and threaten the water security of impacted downstream communities. The magnitude, timing, and persistence of these impacts are difficult to predict due to the lack of high-resolution datasets with adequate coverage to evaluate spatiotemporal trends after a fire. This dissertation moves us beyond the status quo to evaluate post-fire fluvial responses across scales, from the event-scale impacts after the Hermit’s Peak-Calf Canyon wildfire in …