Materials Science and Engineering Commons^™

Distribution Characteristics Of Internal Distress And Maintenance Decision-Making For Asphalt Pavement Based On Three-Dimensional Ground-Penetrating Radar, Li Xiaohua, Song Liang, Ye Wei, Xie Xiaodong, Yang Jiangang, Gao Jie

Journal of China & Foreign Highway

The distribution characteristics of internal distress in pavement structures and the corresponding maintenance decisions are crucial for improving road performance and extending service life.Based on three-dimensional ground-penetrating radar (3D GPR ) technology,this study investigated the internal distress of a 12-kilometer section of both driving and overtaking lanes of an expressway in Hubei Province.High-resolution images of internal pavement distress were obtained,and milling maintenance decisions were optimized by employing these images and a modular decision-making model.Through an efficient and non-destructive technique,the distribution characteristics of internal pavement distress were analyzed,and potential distress types were identified,providing a scientific basis for maintenance decision-making.Data analysis revealed …

Design Of Champlain Bridge In Canada, Xie Yaning, Zhou Yanfeng, Marwan Nader

Journal of China & Foreign Highway

The Champlain Bridge,an iconic gateway spanning the St.Lawrence River in Montreal,showcases not only the excellence of engineering but also becomes an integral part of the city ’s landscape.With a main span of 240 m,the bridge employs a unique single-pylon harp-shaped double-plane cable-stayed structure.The upper pylon is inspired by a tuning fork in its lateral design,while the upper crossbeam artfully mimics the shape of a bow tie,endowing the bridge with a visual beauty that harmoniously blends elegance and strength.The bridge deck,with a total width of 60 m,was the widest double-plane cable-stayed bridge in the world when it was completed.The typical spans …

Modeling And Estimation Of Co2 Capture By Porous Liquids Through Machine Learning, Farid Amirkhani, Amir Dashti, Hossein Abedsoltan, Amir H. Mohammadi, John L. Zhou, Ali Altaee

Chemical and Biochemical Engineering Faculty Research & Creative Works

Porous liquids (PLs) are newly developed porous materials that combine unique fluidity with permanent porosity, which exhibit promising functionalities. They have shown ability to efficiently absorb greenhouse gases such as carbon dioxide (CO₂). Experimental measurement is one approach to determining the solubility of various greenhouse gases in PLs, which has drawbacks such as being expensive and time-consuming. Hence, simulation models are valuable to predict the solubility of CO₂ in various PLs. This work aims to develop machine learning (ML) modeling methods for accurately estimating CO₂ solubility under varying conditions (e.g. PLs, temperature, pressure). Adaptive Neuro-Fuzzy Inference …

Camino—Career Advancement, Mentorship, Inspiration, And Opportunities: A Stem K-12 Outreach Initiative, Hector A. Pulgar, Francisco Zelaya-Arrazabal, Erick Salvador Vasquez, Sebastian N. Martinez Lizana

Chemical and Materials Engineering Faculty Publications

CAMINO is a STEM program designed to promote career advancement, provide mentorship, give inspiration, and offer opportunities for K-12 Hispanic students located in East Tennessee. As part of the educational component of an NSF CAREER grant, the program launched in 2021 and is a collaboration between a research group from the University of Tennessee and one of the high schools with the largest Hispanic populations in the Knoxville Metropolitan area. These students from minority backgrounds may limit their aspirations and may not pursue higher education and/or professional development for numerous reasons, such as limited motivation, insufficient exposure to higher education, …

Entrepreneurially Minded Learning (Eml) Micromoment Activities Generated Using Students' Experiences In A Fluid Flow And Heat Transfer Course, Erick Salvador Vasquez, Megan Morin

Chemical and Materials Engineering Faculty Publications

The Entrepreneurially Minded Learning (EML) Framework involves the 3 C's: curiosity, connections, and creating value. Several design courses, open-ended assignments, and laboratory experiences can successfully lead to EML implementations. However, these implementations require extensive class time and instructor feedback, limiting their use in core engineering courses. Developing EML activities that are active, engaging, and rapid to deploy in a classroom setting can promote the sustained growth of an entrepreneurial mindset (EM). EML micromoment activities are emerging as a practical tool to facilitate the incorporation of the 3 Cs through rapid activity implementations that only last 2 – 30 minutes. These …

Utilization Of Rubber Tire Composition For The Mechanical And Dynamic Performance Of An Energy Dissipation Damper, Ahmed Sami Hasan Al-Osta

Student Works (2020-2029)

Economic development results in a rise in the demand for different items, such as rubber products. Consequently, there is a continuous growth in the amount of waste rubber products generated globally each year. The waste generated from solid tires, composed of non-biodegradable substances, poses significant environmental and public health concerns. Protecting critical buildings, bridges, potentially hazardous industrial operations, and valuable equipment against earthquakes is crucial for ensuring safety and minimizing economic losses. This study aims to evaluate rubber tires' damping mechanical and dynamic properties by optimizing the rubber tire composition. Various rubber compositions were examined to determine the most efficient …

Investigating The Properties Of Eco-Bricks Composed Of Sawdust, Bamboo, And Varying Composition Of Sugarcane Bagasse Ash And Portland Cement, Wilfred Victor C. Marasigan, Julia Sophia Antonia S. Encarnacion, Czyrus Michael A. Bajeta, Alijah F. Gonzales, Juan Carlo T. Gumangan

Sinaya: A Philippine Journal for Senior High School Teachers and Students

With the construction industry contributing nearly 40% of global greenhouse gas emissions, there is a growing need for innovative and sustainable building materials. This research investigates a new eco-friendly concrete brick incorporating sugarcane bagasse ash (SCBA), sawdust, and bamboo fibers. Three eco-brick mixtures, each containing 2% bamboo fiber and 10% sawdust by weight but with varying proportions of Portland cement (PC) and SCBA, were tested against a standard brick for compressive strength, flexural strength, and water absorption. The optimal mixture, with 2% bamboo fiber by weight, 10% sawdust by weight, 85% PC, and 15% SCBA, exhibits compressive and flexural strength …

Shrinkage Study In Photopolymerisable Hybrid Sol-Gel Through Holographic Patterning, Jamshed Aftab, Izabela Naydenova, Tatsiana Mikulchyk

Articles

Photopolymerisation induced shrinkage of holographic materials is one of the main factors which needs to be considered for designing holographic optical elements (HOEs) with high accuracy in light redirection with maximum efficiency. This work studies the shrinkage in photopolymerisable hybrid sol-gel (PHSG) by examining the properties of volume transmission gratings recorded in PHSG layers. It explores both the dependence of shrinkage on the holographic grating parameters (thickness, spatial frequency, slant angle) and the effect of material aging. By using the fringe-plane rotation model, shrinkage is found to have the maximum value of 1.37 % at 765 lines/mm (19.36° slant angle) …

Treatment And Activation Effects On Kaolinite-Based Earth Concrete, Mojtaba Kohandelnia, Maroua Zerzouri, Ammar Yahia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Self-consolidating earth concrete (SCEC) addresses the long construction process of conventional earthen constructions and their structural limitations, while further efforts are needed to enhance its sustainability. This study explores the development of a kaolinite-based self-consolidating earth paste (SCEP) due to their blended powder system, incorporating raw and treated (calcined and ground-calcined) kaolinite under various activation techniques, such as water hydration, sodium hexametaphosphate (NaHMP), and sodium hydroxide (NaOH) activation. The synergistic effect of calcination and mechanosynthesis on rheological, mechanical, structural, and microstructural properties of SCEP were investigated. Mechanically treated kaolinite increased yield stress, plastic viscosity, storage modulus evolution, and build-up index, …

Measurement And Process Relation For Cast Surface Defects, Nachiket Laxman Shinde

Masters Theses

This thesis presents an in-depth investigation into the classification and prediction of surface defects in aluminum sand castings using a combination of experimental trials and machine learning techniques. Key process variables such head height, pouring temperature, resin %, sand type and process were systematically varied to study their influence on defects like veining, and burn-on. Comparative analysis indicated superior performance of the deep learning model in handling nonlinear interactions between process parameters. The study emphasizes the importance of integrating data-driven models with foundry practices to enhance surface quality, reduce rework, and support intelligent decision-making in casting operations.

Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling

Master's Theses

Batteries with higher specific energy and power are essential for extending the range and performance of electric vertical takeoff and landing aircraft (eVTOLs). Anode-free lithium-metal pouch cells offer strong potential at the cell-level but require high compressive pressures to enhance cycle life and discharge performance. These pressures necessitate heavier structural components, reducing packaging efficiency at the module level.

To evaluate this tradeoff, a full-factorial enumeration model was developed to explore viable module designs within a constrained packaging volume. The model scales subsystem masses, enforces design rules and material limits, and accounts for large (~20%) cell thickness changes during cycling.

Results …

Low Earth Orbit Drag Sail Degradation Due To Atomic Oxygen And Ultraviolet Radiation, Hannah Rost

Master's Theses

As the orbital debris population increases, so does the risk of collisions with operational spacecraft. In response, the Federal Communications Commission has shortened the deorbit requirement from 25 years to five years. While natural atmospheric decay was sufficient under the previous guideline, many objects with low area to mass ratios can no longer passively comply. Smaller, non-propellant-carrying space objects such as CubeSats lack the ability to maneuver and must rely on alternative deorbit methods. One proposed solution is to deploy a drag sail at end of life to increase atmospheric drag and accelerate orbital decay. However, exposure to atomic oxygen …

In-Situ Defect Detection In Selective Laser Melting Using Convolutional Neural Networks, Ethan Gaigalas

Master's Theses

This thesis develops and trains a convolutional neural network (CNN) to classify defects in metal parts produced by selective laser melting (SLM) using acoustic emission (AE) data. The model successfully identified porosity and standard build layers with high accuracy but consistently struggled to classify lack of fusion (LOF) defects, regardless of input type, normalization, or class count. These results suggest that while AE signals contain distinguishable features for certain defect types, LOF signals may be too subtle or inconsistent for reliable detection. The study addresses the ongoing challenge of in-situ quality monitoring in metal additive manufacturing, where defects like cracks, …

Investigation Into Silicone-Silicate Conversion Due To Atomic Oxygen In The Low Earth Orbit Environment, Justin T. Self

Master's Theses

Silicones have been widely used over the years in spacecraft for a variety of functions, but atomic oxygen (AO) exposure in Low Earth Orbit causes a silicate (SiO₂) surface layer to rapidly develop on the silicone which results in a permanent change in its thermal and optical properties. Although this silicone to silicate conversion is known to occur, statistical predictions of layer formation as a function of time on orbit are not found in literature. This thesis utilized optical and scanning electron microscopy, Fourier-Transform Infrared Spectroscopy, diffuse reflectance spectroscopy, and nonlinear regression statistical techniques after RF plasma asher …

Degradation Characterization Of Nopal-Based Biopolymer Made From Opuntia Sp. Juice, Beeswax, Animal Protein, And Polyvinyl Alcohol, Logan Williams, Mary Elizabeth Holland, Spencer Williams

Materials Engineering

Since the introduction of polymers in the 1960s, there has been an exponential increase in use. Driven by rapidly growing demand, the volume of polymers in the production, application, and end-of-life stages has surged. The widespread use of these materials has led to escalating environmental pollution, which disrupts ecosystems, and contributes to global ecological degradation. While advancements in recycling technologies and infrastructure have shown promise, they have not maintained pace with polymer production and disposal. This imbalance warrants research into sustainable alternatives. Environmentally benign polymers derived from renewable sources and exhibiting minimal ecological impact at the end of their life …

Performance Evaluation Of Aminated Multi-Walled Carbon Nanotubes Incorporated With Green Synthesized Iron Nanoparticles For Toxic Dyes Sequestration From Textile Wastewater, Titus Chinedu Egbosiuba, Cynthia Chukwuemeka, Jonah Chukwudi Umeuzuegbu, Nwanneka Chibuzo Mmonwuba, Ugochukwu Ewuzie, Monday Uchenna Okoronkwo, Valentine Chikaodili Anadebe, Saheed Mustapha, Ambali Saka Abdulkareem, Jimoh Oladejo Tijani, Ashish Patel, Virendra Kumar Yadav

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study evaluates the performance of aminated multi-walled carbon nanotubes (AM-MWCNTs) integrated with zerovalent iron nanoparticles (ZVI) synthesized using cashew leaf (Anacardium occidentale) extract (AM-MWCNTs@ZVI) for the removal of Congo Red (CR) and Methylene Blue (MB) dyes from textile industrial wastewater. The nanocomposite was characterized using FTIR, XRD, BET, HRSEM, and HRTEM analyses, confirming its functional groups, crystalline structure, and enhanced surface area of 1050.4 m²/g. The ecological risk degree of the textile pollutants was assessed to determine the percentage concentrations of crystal violet, Congo red, methyl orange, methylene blue and rhodamine B. Batch adsorption experiments identified optimal …

Effect Of Manufacturing And Machining Process On Recycled Composite Connecting Rods Under Tension And Compression, Walter W. Oppelt

Master's Theses

Carbon fiber reinforced polymer (CFRP) is an engineering material renowned for its high-strength and low-density material properties. Such properties make CFRPs especially useful for applications across many industries, including aerospace, automotive, marine, sporting goods, oil and gas, and more. However, with such favorable material properties comes the cost of high energy usage required to produce raw carbon fiber. Recycled carbon fiber (rCF) has emerged as a promising alternative, offering a significant reduction in energy usage. This research explores the viability of applying recycled CFRPs to internal combustion engines to both reduce energy costs during manufacturing and while in use. Mechanical …

Myceli-Yum: Elucidating Structure-Property Relationships For Polymer Degradation By Mycelial Digestion, Jordan Scott Ford

Master's Theses

Since the industrial entrance of polymer plastic materials, plastic has become ubiquitous in both everyday use and waste. Due to inefficiencies and knowledge gaps, current recycling methods are not able to account for the high scale of plastic waste, resulting in the bulk of this waste being landfilled, mishandled, and deposited in the environment. Mycelium, the microorganism responsible for fruiting mushroom bodies and mold growth, holds potential to reduce plastic waste and can potentially be utilized as a method of industrial recycling. Following a drug-design approach, the active site of mycelial enzymes responsible for natural biopolymer degradation have been assessed …

Design Principles For Robotic-Controlled 3d Printing Of Soft Tissue-Mimicking Materials, Karina Mealey

Master's Theses

Geometrically and physically accurate 3D models are emerging as essential tools for surgeons in pre-operative planning and training, but current methods of producing these models are not sufficient. Existing solutions have downsides such as high costs, long and tedious production times, high complexity resulting in a lack of scalability, or an inability to meet material requirements for accurately simulating human tissue.

The objective of this work is to develop principles for a low-cost, easy-to-use 3D printing system capable of prototyping with soft tissue-mimicking materials. To pursue this goal, a MyCobot280 robot arm was used as the mechanism to explore the …

Thermal Modeling Techniques For Additively Manufactured Porous Metals, Lucas D. Rambo

Master's Theses

Advances in additive manufacturing have enabled the creation of metallic components with tailored porosity, offering design flexibility for thermal, structural, and fluid transport applications. This thesis investigates the effective thermal conductivity (ETC) of porous Inconel 625 (IN625) and Inconel-ceramic composites (IN625-RAM2) fabricated by Laser Powder Bed Fusion (LPBF) using Elementum 3D’s PermiAM technology. Experimental measurements of thermal conductivity using the laser flash method are compared to numerical models built from micro-computed tomography data. Simulations were performed using both finite element (FE) and finite volume (FV) methods to evaluate thermal transport in real microstructures. The study investigates the effects of micro- …