Structural Materials Commons^™

Lafe0.925ti0.075o3 Perovskite Coated With Ethyl Cellulose: A High-Stability, Low-Hysteresis Platform For Advanced Humidity Sensing, Akhmad Futukhillah Fataba Alaih, Djoko Triyono, Rifqi Almusawi Rafsanjani

Makara Journal of Science

Humidity sensors are pivotal in numerous sectors, such as environmental monitoring, industrial automation, and health-care. This study presents the fabrication and detailed evaluation of an advanced humidity sensor using ethyl cellulose (EC)-coated LaFe_0.925Ti_0.075O₃ (LFTO) perovskite nanoparticles synthesized via the sol-gel method. The LFTO nanopar-ticles exhibited a mesoporous structure with an enhanced surface area, which significantly improved their moisture adsorption capabilities. The innovative application of EC coating addresses critical substrate adhesion issues, enhancing mechanical stability without compromising sensor sensitivity. Comprehensive performance evaluations revealed minimal hysteresis (

A Hybrid Mechano-Thermal Route To Synthesize Reactive Pozzolans From Clay Minerals: A Case Of Kaolinite, Oluwadamilare Charles Adesina, Bryan K. Aylas-Paredes, Brian R. Cherry, Luciano A. Gobbo, Aditya Kumar, Narayanan Neithalath

Materials Science and Engineering Faculty Research & Creative Works

Aluminosilicate resources from unconventional sources offer promising potential for developing low-carbon supplementary cementitious materials (SCMs), yet their activation typically requires energy-intensive thermal processing. Kaolinite is a geographically abundant and highly attractive precursor clay mineral to reduce the clinker factor in concrete. By integrating mechano- and thermo- chemistry sequentially in a novel hybrid mechano-thermal activation (MTA) strategy for clay mineral activation, the dehydroxylation of pure kaolinite polymorphs KGa-1b and KGa-2 for enhanced pozzolanic reactivity is unlocked at temperatures that are lower than those needed for conventional thermal activation (TA). The mechano-chemical activation (MCA) step that induces significant structural defects and disorder …

A Performance-Weighted Environmental Assessment Of Ultra-High-Volume Fly Ash Substitution In Portland Cement Concrete, Youngguk Seo, M.A. Karim, Teddy Tzvetkov, Joshua Hardy

Faculty Articles

Fly ash substitution for cement in Portland cement concrete (PCC) has been regarded as a sustainable solution, but its widespread application remains constrained by concerns over mechanical performance and durability of PCC, especially at higher replacement rates. This study evaluates PCC mixes incorporating fly ash Type C (FA-C) or Type F (FA-F) across cement replacement rates from 10% to 90%, tracking fresh-state workability, compressive strength, and surface electrical resistivity at 7, 14, and 28 curing days. A process-based life cycle assessment (LCA) with the TRACI 2.1 method quantified global warming potential (GWP, kg CO₂/m³) under a …

Characterization Of The Thermally Driven Red Hue Effect In Coated And Uncoated Concrete Systems: Implications For Post-Fire Assessment In Wildland Urban Interface Communities, Juan C. Palominos Jr

Master's Theses

The increasing frequency and intensity of Wildland-Urban Interface (WUI) wildfires, such as the destructive 2025 Pacific Palisades Fire that destroyed over 6,000 structures, have underscored the urgent need for rapid post-fire safety assessment methodologies. This study sought to quantitatively characterize the Thermally Driven Red Hue Effect (TRHE), a unique, irreversible color shift observed in architectural coatings and concrete substrates, to determine its reliability as a permanent visual record of thermal exposure. Concrete substrates were formulated with three distinct coarse aggregates: gold granite (14.7% Fe), red cinder (22.4% Fe), and green rock (33.6% Fe) and coated with a 20 PVC waterborne …

Electropulse Annealing: Phase Composition Of Tial6v4, Vaughn Eckhardt, Ethan Croke, Ian Baker, Russ Taylor

Wetterhahn Science Symposium Posters

Titanium alloy TiAl6V4 is the most ubiquitous titanium alloy used for dental care, aerospace manufacturing, and for high performance vehicles. The material typically undergoes a thermal heat  treatment, but electropulse annealing is another process that involves sending current through the material to heat it up at a quicker rate. The rate of post-annealing cooling is high, and around the material's critical point, its two components, alpha and beta phase, change in relative concentration. After testing multiple current densities and temperatures, in general, as the current density that the sample received during electropulse annealing decreased, both the alpha and beta phases …

Optimizing Wind Turbine Blades Using Fiber-Reinforced Composites, Rayan A. Akeel

Discovery Day - Daytona Beach

This project explores how fiber-reinforced materials can improve wind turbine blade performance by making them lighter and more durable. It will examine different fiber types, their fabrication methods, and their impact on efficiency and strength.

An Analytical Framework For Quantifying Urban And Community Resilience To Natural Hazards From Cell-Phone Gps-Location And Traffic-Flow Data, Georgios Chatzikyriakidis

Civil and Environmental Engineering Theses and Dissertations

Urban areas are increasingly exposed to natural hazards while accommodating a growing share of the global population, yet a consistent science-based framework for quantifying urban and community resilience remains lacking. This dissertation develops a physics-based analytical framework grounded in statistical mechanics and the quantitative theory of Brownian motion. A city is conceptualized as a complex medium in which citizens move analogously to Brownian particles within a viscoelastic environment, influenced by socioeconomic interactions and infrastructure functionality.

A central premise is that urban resilience, interpreted as engineering resilience (an outcome), can be quantified through a single metric: the mean-square displacement MSD=⟨r²(t)⟩, of …

Plastic Material Analysis And Bonding In Small Aquatic Vessels, Andrew R. Orr

Honors College Theses

This project presents the design and development of a suitable vessel for small-scale aquatic applications. The developed project is used for a remote-controlled duck hunting system, and the parameters of the design are based on the requirements for the system as a whole. Traditionally, plastics are fabricated using blow molding to create a single seamless form. However, for small-scale prototyping with limited resources, this method of fabrication is unsustainable for short-term, non-industrial design applications. As a result, an existing longer hull is selected and shortened to meet the required project length. The project evaluates multiple initial hull designs, ultimately selecting …

Ballistics Characterization Of Micro-Truss Reinforced Lunar-Inspired Geopolymer Concrete For Space Construction, Phoebe G. Johnson

Honors Theses

This research investigates the ballistics response and compressive strength of a Fly Ash/ Lunar Regolith hybrid geopolymer concrete developed for space construction. The study aimed firstly to optimize the Fly Ash/ Regolith mix ratio for maximum mechanical performance and secondly, to evaluate the effectiveness of carbon-fiber micro-truss reinforcement, produced by 3D printing, in mitigating damage from high-velocity impacts. Concrete specimens with varying Fly Ash-to-Regolith ratios (100-50% Fly Ash) were fabricated and tested under compression and ballistic loading. Compressive strength tests followed ASTM C109 using a 110 Kip 810-MTS testing apparatus on both unreinforced and reinforced 2” cubes. For unreinforced samples, …

Brine Solidification And Metals Sequestration Using Lignocellulosics, Frank Kvietok

World of Coal Ash Proceedings

Coal ash has historically been used as a convenient, on-site solidification material for brines generated from flue gas desulfurization at power plants. As alternate utilization scenarios are developed for coal ash, lignocellulosic (wood-based) sorbents can serve as a highly efficient substitute for the solidification process. Results will be shared for a variety of different brine types: thermally reduced, thermally reduced and neutralized, and reverse osmosis. In addition to solidification performance, which demonstrated a 3-4x mass of liquid vs mass of sorbent factor, studies were conducted to quantify the strength of binding to the wood-based sorbent for a broad range of …

Practical Guidelines For Pump Testing Of Ccr: Workflow, Design, And Lessons Learned., Nathanial Keller, Brian Hennings, Vic Modeer, Katie Moran

World of Coal Ash Proceedings

This session presents a streamlined approach for pump testing of coal combustion residuals (CCR) to maximize hydraulic information with limited well installations, variable pumping rates, and short tests. Pre-test forward modeling identifies well offsets (typically 5–10 ft) and test durations (~2–6 hours) to yield measurable and analyzable drawdown at observation wells despite low pumping rates. Field execution consists of short step-drawdown testing to evaluate well specific capacity and select pumping rates for a constant rate test with one or more observation wells. Test results facilitate analysis of transmissivity and storativity of the CCR. Applied at two Midwestern sites with different …

Before The Limit Hits: Lessons From A Proactive Construction Air Monitoring Program, Brian Egan, Nicholas Golden, Wendy Depp

World of Coal Ash Proceedings

This presentation describes a comprehensive air monitoring program designed to protect workers and nearby neighborhoods during ash pond closure work. The program uses three main components: project (or boundary) monitoring at the site perimeter to track dust near the project boundaries, work area monitoring placed near active construction zones, and personal sampling on individual workers at regular intervals. Together, these approaches provide data on both community impacts and worker exposures, helping the team respond quickly when levels approach action limits. The Teams actions prior to exceedance of regulatory limits has helped prevent exposures. The talk will explain how monitors are …

Integrating Advanced Geochemical Workflows With Modern Statistical Tools To Improve The Decision-Making Process At Ccr Sites, A Case Study, Glenna Thomas

World of Coal Ash Proceedings

While statistical assessment provides the foundation for CCR compliance reporting, incorporating a holistic geochemical framework transforms statistics from a compliance requirement into a powerful predictive tool. Strategic geochemical insight established the basis of understanding needed to support successful statistical approaches and to ensure that statistical outcomes reflect actual groundwater behavior. Whether it is trend analysis, delineating source mechanism, or updating geochemical conceptual site models (GCMs), geochemical context provides the technical foundations for statistical outputs and methods. A continuously refined GCSM enhances the ability to anticipate how groundwater chemistry should evolve, improving interpretation and predictive capability. This allows practitioners to understand …

Monitored Natural Attenuation Evaluation And Additional Characterization Of A Ccr Unit Lithium Groundwater Plume, Matt Barickman, Adam Piestrzeniewicz Pg

World of Coal Ash Proceedings

Monitored Natural Attenuation (MNA) refers to the reliance on natural attenuation processes (within the context of a carefully controlled and monitored site cleanup approach) to meet groundwater protection standards (GPS) for a CCR unit within a reasonable time frame (USEPA, 1999). MNA is being evaluated as an adaptive management strategy for a CCR unit groundwater plume with statistically significant lithium concentrations above GPS, though with little risk of offsite migration. A previous MNA evaluation was performed for the lithium plume following the United States Environmental Protection Agency (USEPA) “tiered lines of evidence approach” (USEPA, 2015), which determined that there were …

Simplified Approximate Procedure For Assessing The Implications Of Updated Usgs Seismic Hazard Models On Seismic Stability Assessments Of Ccr Impoundment Facilities, Nick Mcclung, Matt Bishop, Adrian Pena-Iguaran, Seda Gokyer-Erbis

World of Coal Ash Proceedings

Selection of appropriate seismic design ground motions remains a key challenge for seismic stability assessments of coal combustion residual (CCR) impoundment facilities, particularly where regulatory guidance does not specify a required hazard model. This paper examines the implications of using Uniform Hazard Spectra (UHS) derived from the 2014 versus the 2018 U.S. Geological Survey (USGS) National Seismic Hazard Model (NSHM) for seismic amplification and stability evaluations of the Tennessee Valley Authority (TVA) Widows Creek Fossil (WCF) Plant CCR Management Units. The 2018 NSHM incorporates updated understanding of seismicity in the central and eastern United States and generally predicts higher ground …

Establishing Groundwater Monitoring Systems Under The Legacy Rule: A Systematic Approach For Utilities, Chris Hoglund

World of Coal Ash Proceedings

The USEPA’s Legacy CCR Rule introduces new requirements for establishing groundwater monitoring systems at Legacy Surface Impoundments (LSIs) and Coal Combustion Residual Management Units (CCRMUs). These requirements present unique challenges for electric utilities, particularly at inactive or historically operated facilities where subsurface data are limited and CCR units may have nontraditional configurations such as linear roadways, elongated embankments, or distributed disposal areas. Utilities must also determine how best to apply single-unit or multi-unit monitoring approaches, integrate newly regulated units into existing monitoring networks, and align monitoring system design with planned closure strategies. This presentation outlines a systematic, defensible framework to …

Risk Evaluation Of Linear Coal Combustion Residual Management Unit (Ccrmu) Fills, Qian Zhang, Andrew Bittner, John Kondziolka, Masoud Arshadi

World of Coal Ash Proceedings

In 2024, the US Environmental Protection Agency (US EPA) established new regulations for coal combustion residual management units (CCRMUs), defined as coal combustion residual (CCR) deposits placed on power plant properties outside of landfills or surface impoundments. US EPA supported the rulemaking with modeling-based risk analyses and established regulatory requirements based on fill size. Linear CCRMU, such as backfill along pipelines or haul roads, have individual segments that may be composed of a small amount of mass below the threshold for regulation, but the cumulative mass over the full linear feature extent may exceed regulatory thresholds. This study applies US …

Application Of Mine Tailings Flow Failure Assessment On Ccr, Zachary Fallert

World of Coal Ash Proceedings

A new geotechnical stability analysis method has been implemented for a CCR surface impoundment to aid in design for temporary cut slopes and final closure grades. Conditions have come to light after significant tailings dam failures occurred across the globe, specifically those exhibiting flow failures (i.e. failures in which tailings behave a liquid and flow out of the facility). These failures have come under intense scrutiny as the failures pose significant risk to public safety and the environment and have been observed in CCR. Additionally, static liquefaction has arisen as another potential but less well understood causative mechanism. As the …

Lessons Learned: Commissioning An Fgd Wastewater Treatment System, Bella Triolet, Mckale Grant, Louis Manigault

World of Coal Ash Proceedings

Stantec recently supported commissioning a flue gas desulfurization (FGD) Wastewater Treatment System in accordance with the 2020 Environmental Protection Agency (EPA) Effluent Limitations Guidelines (ELG) Rule, which requires that coal fired power plants meet their more stringent requirements by December 31, 2025. With the addition of the 2024 EPA ELG Rule, coal fired power plants will now be expected to move to zero liquid discharge (ZLD) systems or permanently cease coal combustion by 2034. Due to this change, it is likely that coal fired power plants will be looking to design and install ZLD systems within the next decade. While …

Risk Evaluation Of Linear Coal Combustion Residual Management Unit (Ccrmu) Fills, Qian Zhang, Andrew Bittner, John Kondziolka, Masoud Arshadi

World of Coal Ash Proceedings

In 2024, the US Environmental Protection Agency (US EPA) established new regulations for coal combustion residual management units (CCRMUs), defined as coal combustion residual (CCR) deposits placed on power plant properties outside of landfills or surface impoundments. US EPA supported the rulemaking with modeling-based risk analyses and established regulatory requirements based on fill size. Linear CCRMU, such as backfill along pipelines or haul roads, have individual segments that may be composed of a small amount of mass below the threshold for regulation, but the cumulative mass over the full linear feature extent may exceed regulatory thresholds. This study applies US …