Engineering Commons^™

Stabilization Of Cr³⁺ Using Iron Rich Slag-Derived Phosphate Cement: An Integrated Solution For Heavy Metals And Hazardous Solid Wastes, Ting Huang, Hongyan Ma, Zhongqiu Luo, Xintao Zhou, Zhengqing He, Peiwen Lv, Xiunan Cai, Pingyan Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A novel iron-based phosphate cement (IPC), derived from iron-rich smelting slag (ISS), was developed as a sustainable and efficient binder for the stabilization/solidification of trivalent chromium (Cr³⁺). The mechanical properties, hydration behavior, microstructure, leaching toxicity, chromium chemical forms, and environmental safety of chromium-stabilized iron phosphate cement (CIPC) were thoroughly evaluated. The results showed that, with a mass ratio of ISS to ammonium dihydrogen phosphate (ADP) of 2.0, and even with the addition of 20 % chromium nitrate nonahydrate (CN), the compressive strength of CIPC reached 4.2 MPa after curing for 28 d. Furthermore, chromium leaching was well below …

Influence Of Mixing Duration And Absorption Characteristics Of Superabsorbent Polymers On The Fresh And Hardened Properties Of High-Performance Concrete, Yu Cun Gu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the combined influence of superabsorbent polymers (SAPs) with distinct absorption kinetics and extended mixing sequences on the rheological, mechanical, and transport properties of high-performance concrete (HPC). Two SAPs—an ionic acrylamide-co-acrylic acid copolymer (SAP-P) and a non-ionic acrylamide polymer (SAP-B)—were incorporated at an internal curing level of 100%. The impact of extended mixing times (3, 5, and 7 min) following SAP addition was systematically evaluated. Results showed that longer mixing durations led to increased superplasticizer demand and higher plastic viscosity due to continued water absorption by SAPs. However, yield stress remained relatively stable owing to the dispersing effect …

Comparative Study On The Long-Term Performance Of Bmd Mixtures Prepared Using Different Sample Preparation Techniques And Superpave Mixtures Under Varying Pavement Structures, Amarjeet Tiwari

Graduate Theses and Dissertations

Asphalt mix design has advanced significantly since the 1930s, with Balanced Mix Design (BMD) emerging to address durability concerns found in the Superpave method by optimizing binder content based on performance criteria. The performance of bituminous mixtures can be assessed through laboratory testing. These tests require proper sample preparation, and various techniques are employed for this purpose. Understanding the differences between these techniques is essential for the successful application of bituminous mixtures in the field. The objective of this study is to assess the differences in the predicted long-term performance of two sample preparation techniques, Lab Mix Lab Compacted (LMLC) …

Coupling Effect Of Abrasion And Erosion On Ultrahigh-Performance Seawater-Sea Sand Concrete, Dawei Ding, Wei Zhang, Lanqin Wang, Hongyan Ma, Biqin Dong, Song Han, Hongjian Xu, Dongshuai Hou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Preparing ultrahigh-performance seawater-sea sand concrete (UHPSSC) to mitigate the scarcity of freshwater and river sand resources has generated considerable recent research interest. However, the deterioration mechanisms of UHPSSC under the effect of abrasion and erosion remain unstudied. In this paper, the underwater steel ball method was conducted to evaluate the impact of seawater, sea sand, steel fiber, and seawater abrasion on the abrasion resistance of UHPSSC. Then the stress erosion models of calcium-silicate-hydrate (C-S-H) were constructed to investigate the degradation mechanisms of UHPSSC under the effect of external stress and seawater erosion. The results show that the application of seawater …

Valorizing Cement Kiln Dust And Glass Powder: A Binder Study On Sustainable Partial Cement Replacement, Sai Kiran Simhadri

Civil & Environmental Engineering Theses & Dissertations

The production of cement ranks as a major source of global CO₂ emissions because of the high energy requirements needed to create clinker. The construction industry is actively seeking ways to reduce its carbon footprint. Utilizing industrial waste materials to partially replace cement can lower emissions. This research evaluates a ternary binder system which uses Cement Kiln Dust (CKD) and Glass Powder (GP) to replace a portion of Type IL (Portland Limestone) cement. The mixes were made with a fixed water-to-binder ratio of 0.44 and contained 15% GP by mass while the CKD content ranged from 0% to 10%. The …

Navigating Transportation Barriers: Older Adults’ Familiarity With New Mobility Options And Perceptions Toward Autonomous Vehicles In Arkansas, Arna Nishita Nithila, Suman Kumar Mitra, Michelle Gray, Alishia Juanelle Ferguson, Jennifer D. Webb

Civil Engineering Faculty Publications and Presentations

The objective of this study is to analyze older adults’ familiarity with new transportation options (ride-hailing services, bike-share services, and shared e-scooter services) and their perception towards autonomous vehicles (fully autonomous cars), as well as how transportation barriers influence their familiarity and perceptions, in Arkansas, a predominantly rural state. Data from 775 older adults aged 60 years or older were collected between October 2021 and October 2022. To fulfill the study objective, the study used Latent Class Cluster Analysis to segment older adults into classes based on their familiarity with new transportation options and their perceptions of autonomous vehicles. The …

Seismic Performance Assessment Of Fatigue-Damaged Cantilever Overhead Sign Structures Using Near-Field Ground Motions, Yeasin Ahmed

Open Access Theses & Dissertations

Cantilever overhead sign support (COSS) structures are one of the most common features of transportation systems, providing navigational information to motorists. The slender geometry, lightweight design, and welded connection at the base make COSS structure susceptible to fatigue cracking under long term cyclic loading from wind-induced galloping, truck-induced gust pressure and so on. COSS structures are traditionally designed considering nominal wind conditions. However, rising incidents of seismic activity in regions like Dallas-Fort Worth related to industrial injection wells in the Permian Basin have created a serious concern regarding the seismic performance of potentially fatigued-damaged COSS structure. The interaction between already …

Application Of Distributed Fiber Optic Sensing (Dfos) For Monitoring Asphalt Pavement Strains Under Accelerated Loading Conditions, Sebastian Morales

Open Access Theses & Dissertations

This thesis presents a study on the application of Distributed Fiber Optic Sensing (DFOS) technology for detecting pavement's strain response with high spatial resolution. Using a Rayleigh-based optical frequency domain reflectometry (OFDR) system, DFOS sensors were calibrated and embedded in full-scale asphalt slabs subjected to accelerated loading using a Model Mobile Load Simulator 3 (MMLS3). Calibration of the DFOS sensors was conducted using a three-point bending flexural test with known load conditions and reference strain gauges to validate theoretical and numerical models. The results demonstrate DFOS's capability to detect pavement response under static and dynamic loading, as well as changes …

Building Services Engineering July/August 2025

Building Services Engineering

No abstract provided.

Wires, Roads, And Real-World Challenges: An Interdisciplinary Case Study Bridging Roadway And Electric Utility Design, Juliann A. Lloyd

All Theses

Electric utilities are a foundational component of modern society and depend heavily on civil engineers for planning, design, construction, and maintenance. However, educational content related to this industry is often underrepresented in civil engineering programs. To bridge this gap, a case study activity was implemented in two transportation engineering courses at Clemson University. The case study introduced students to the integration between electric utility infrastructure and roadway design by simulating a realistic and common conflict scenario faced by Departments of Transportation (DOTs) nationwide.

Students were placed in interdisciplinary teams, with each member assigned a specialized role such as Land Agent, …

Modeling Disaster Resilience Through A Human-Centered Lens: Exposure, Vulnerability And Adaptation, Tong Liu

All Dissertations

The core of reframing and operationalizing disaster resilience with a human-centered lens is to incorporate concepts from socio-ecological resilience into engineering resilience to better understand the humans’ capability for disaster adaptation. Existing studies have drawn practical implications by identifying actionable thresholds for infrastructure systems under disasters, which can be easily applied by policymakers, emergency managers and municipal agencies. However, how individuals interact with, respond to, or adapt under these infrastructure thresholds remain understudied. This hinders the operationalization of disaster resilience at the human scale.

First, I examined exposure by analyzing how configuration and distribution of urban infrastructure systems, such as …

Studies On The Effects Of Operator Fatigue On Performance, Trust, And Workload Demand In Human-In-The-Loop Ai-Enabled Drone Systems, Snowil Lopes

All Dissertations

Civil infrastructure must be regularly inspected to ensure its safety and reliability. Traditionally, risk engineers performed these inspections manually and in person. However, with the introduction of drones equipped with artificial intelligence (AI), inspections of civil infrastructure can now be conducted remotely. These AI-enabled drones capture and analyze images, helping engineers monitor large and complex structures from a distance. However, working with integrated systems consisting of multiple drones, especially those with varying levels of reliability, can be challenging. Operators must divide their attention, determine how much to trust each drone, and manage mental workload, which can affect their performance. Another …

Drift Dynamics Of Early Life-Stage Invasive Carps, Saurav Karki

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Asian carp species pose significant ecological threats to North American freshwater systems due to their invasive nature and prolific reproduction. Their semi buoyant eggs develop while drifting downstream with the river current. Understanding early life-stage transport is therefore critical for predicting recruitment potential and guiding management efforts. Existing fluvial egg drift models, including those relying on 1-D hydraulics and fully 3-D CFD-based models, are either inadequate for complex braided rivers or too computationally demanding for large-scale application. The Platte River in Nebraska, characterized by wide, shallow, multi-threaded channels, is dominated by two-dimensional flow conditions, making a depth-averaged 2-D modeling approach …

The Significance Of Snow In Hydrometeorological Extremes, Sinan Rasiya Koya

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Snow is the largest natural reservoir on Earth. It accumulates water during the cold and dry months and releases it during warm and dry months. Societies, especially in the extratropical zone, heavily depend on snow as their freshwater resources, resulting in the massive economic value of snow. The recent changes in snowpacks and associated processes are concerning. We are susceptible to disruptions in snow processes, which can have disastrous implications. Yet the importance of snow is often not realized by a wider population. There are limited studies quantifying snow-related extremes, partly stemming from the limitations of existing methodologies.

This dissertation …

Non-Destructive Strength Monitoring Of Air-Entrained Concrete Via Electromechanical Impedance Technology, Xiangrui Kong, Rui He

Discovery Undergraduate Interdisciplinary Research Internship

Accurate monitoring of concrete strength during curing is crucial, particularly in regions subject to harsh weather conditions, such as freeze-thaw cycles in Indiana. Air entrainment is crucial for durability, yet it can significantly reduce concrete strength, making timely and precise strength assessments vital. The primary objective of this study is to develop a non-destructive and real-time monitoring framework for evaluating mortar strength using electromechanical impedance (EMI) sensors and ultrasonic scanning technology.

This research holds significant value as it addresses the critical need for continuous, reliable concrete strength monitoring, potentially reducing reliance on destructive testing methods, which are costly and time-consuming. …

A Multi-Scale Numerical Analysis Of Wave Propagation Through Coastal Vegetation Using Proteus & Xbeach, Cole M. Statler

LSU Master's Theses

Coastal vegetation attenuates waves in the nearshore zone and protects shorelines from storm surge and wave action. It also traps nutrients and sediment, and participates in the formation of land over longer time scales. These features of vegetation make it a common component of nature-based engineering projects. Interaction of water waves and flow with vegetation, however, can involve unsteady and turbulent flow, non-hyrdostatic pressure effects, and air entrainment that can hinder the use of simple parametric representations of vegetation drag. XBeach, a one- and two-dimensional production model applies reduced-order methods, prioritizing computational efficiency. Vegetation is represented in XBeach as a …

Fresh And Mechanical Properties Of Self-Compacting Concrete Using Kaolin Limestone Blend And Hybrid Slag Blend, Selesca Devi S

Theses and Dissertations

This study examined the consequences of mono and hybrid natural fibers on the mechanical and fresh properties of self-compacting concrete (SCC), in response to the growing demand for environmentally friendly building materials. In mono fiber, Abaca fiber (AF) at 0.25% and 0.5% dosage, basalt fiber (BF) from 0.25% to 2% at 0.25% increments, and sisal fiber (SiF) from 0.25% to 1.5% at 0.25% increments were evaluated through slump flow diameter, T500, compressive and tensile strength. AF at 0.25% ensured good flow with 6.6% and 4.16% higher compressive and tensile strength over 0.5% AF. SiF up to 1% improved strength but …

Research On Node-Improved Energy Dissipation Wear Model For Fretting Fatigue Prediction In Railway Press-Fit Shaft, Hang Wang, Lijun Zhang, Weijian Zhang, Hongtao Li, Hong Chi, Kai Yang, Jixu Zhou, Li Ai

Civil Engineering Faculty Publications

As a key component of the traveling system of high-speed trains, the axle is crucial for its safe operation. The current research on the fretting wear and fatigue development of shafts suffers from the problems of low local simulation accuracy of the wear model and the lack of detection and validation methods for the dynamic expansion of wear and fatigue. To this end, this study firstly proposes a new node-improved form of energy dissipation wear model, which is more sensitive to the contact behavior of the asperity body in the overfilled region and the energy transfer process; it exhibits wear …

Biochar-Based Filtration And Barrier Systems For Urban Stormwater Treatment, Krishna R. Reddy

Stormwater Drainage Conference

Conference that deals a wide range of issues dealing with stormwater drainage. Professor Krishna Reddy of University of Illinois Chicago presented an invited talk titled "Biochar-Based Filtration and Barrier Systems for Urban Stormwater Treatment"

Utilization Of Ftir-Atr For Material Characterization And Forensic Analysis, Helmut Leodarta, Ahmed S. El-Ashwah, Punyaslok Rath, Magdy Abdelrahman, William G. Buttlar

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The growing use of chemical modifiers and additives in asphalt mixtures necessitates a reliable system for their identification and quantification, crucial for quality control, assurance, and forensic investigations. Fourier Transform Infrared (FTIR) spectroscopy offers a cost-effective method by analyzing the interaction of infrared light with chemical groups, producing distinct spectral fingerprints. This study evaluates 44 materials, including binders, warm mix additives (WMAs), rejuvenators, release agents, and concrete admixtures. It also assesses the ability of FTIR testing to identify and quantify chemical changes and aging in asphalt binders with rejuvenator addition. An Attenuated Total Reflectance (ATR) accessory was employed for practical …

Ftir Characterization Of Asphalt Sara Fractions In Response To Rubber Modification, Mohyeldin Ragab, Eslam Deef-Allah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt–rubber binders (A-RBs) have a long and deep history of use; however, little is known regarding the interrelated chemical behaviors and miscibility of rubber with the asphalt fractions [saturates, aromatics, resins, and asphaltenes (SARA)]. This study comprehensively attempted to address this knowledge deficiency by employing Fourier transform infrared spectroscopy (FTIR) to investigate the chemical evolution of A-RBs. A-RB interacted at 190 °C and 3000 min⁻¹ for 8 h was deemed to have the optimal rheological performance. FTIR of the liquid fractions of A-RB 190–3000 showed a prominent chemical shift in the SARA fractions, with new peaks that showed rubber …

Characterization Of The Effects Of Waste Mullite Powder On Seawater Sea Sand Cementitious Materials, Xiao Sun, Zehui Zhou, Wenjie He, Yudong Bi, Yao Wang, Hengrui Liu, Rui Zhong, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Maintaining the durability of coastal concrete structures while reducing construction costs remains a formidable challenge. Drawing inspiration from the volcanic concrete used by ancient Greeks and Romans, this study explores the feasibility of using waste mullite powder (WMP) with a high alumina content in seawater sea sand concrete to conserve natural resources and enhance durability. The experimental results demonstrate that the incorporation of seawater and WMP exerts detrimental impacts on the flow characteristics and workability of cementitious composites. While the sulfate content in seawater and sea sand can bolster the early strength of sea sand seawater concrete, sulfate attack compromises …

Data-Driven Prediction Of Binder Rheological Performance In Rap/Ras-Containing Asphalt Mixtures, Eslam Deef-Allah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt recycling technologies have advanced considerably over the last few decades with the utilization of reclaimed asphalt pavements (RAP) and recycled asphalt shingles (RAS). Characterizing aged and heterogeneous binders in these mixtures is challenging, particularly with limited extracted binders. This study suggests a data-driven framework that considers the rheological, chemical, and thermal characteristics to predict the binders' performance. Ninety-seven mixtures with 0–35% of the asphalt binder replaced with RAP/RAS binders were included as cores from the field, plant-produced mixtures, and laboratory-fabricated mixtures. The binders were chemically quantified using aging, aromatic, and aliphatic indices. Thermal analyses of the binders involved the …

Elucidating The Impact Of Common Stormwater Pollutants On Antibiotic Resistance: The Role Of Heavy Metals, Nutrients, And Salts, Kassidy N. O'Malley, Patrick J. Mcnamara, Walter M. Mcdonald

Civil and Environmental Engineering Faculty Research and Publications

Antibiotic resistance poses a significant global health threat, and the urban water cycle presents an opportunity to augment or limit the spread of antibiotic resistance. In particular, stormwater runoff has recently been revealed as a key conduit for antibiotic-resistant bacteria (ARB). The specific role of stormwater pollutants, however, on antibiotic resistance has not been isolated. Understanding the impact of specific pollutants common to stormwater could help optimize design and operation of stormwater systems for management of antibiotic resistance. The objective of this research was to establish the potential contributions of common stormwater pollutants to antibiotic resistance proliferation. Lab-scale stormwater microcosms …

Feasibility Of Using Recycled Waste Plastic In Concrete Pavements In Nebraska, Amasi Hajahja

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Waste plastic (WP) is a growing environmental concern due to its non-biodegradable nature, large-scale production, and harmful impact on natural resources. With nearly 75% of WP in the United States ending up in landfills, effective recycling strategies are urgently needed. In parallel, the limited availability of natural aggregates highlights the need for alternative materials in concrete construction. This study investigates the feasibility of using recycled waste plastic (RWP) in concrete mixtures, both as aggregates and fibers for rigid pavement applications in Nebraska. Concrete mixtures were prepared by partially replacing natural fine aggregates with recycled plastic aggregates (RPA) at replacement levels …

Integrating Ensemble Hydrologic Forecasts With Policy Optimization Models For Forecast-Informed Reservoir Operations (Firo), Alessandra Estefania Perez Salas

Theses and Dissertations

Effective reservoir management in hydrologically variable regions such as California’s Central Valley faces increasing pressure to balance flood control, water supply reliability, hydropower generation, and ecosystem health. Traditional rule-based operations, while operationally simple, often lack the adaptability required to respond to real-time hydrologic conditions and forecast uncertainty. This study presents an integration of a policy tree optimization model with ensemble streamflow forecasts to enhance Forecast-Informed Reservoir Operations (FIRO) at Folsom Reservoir. Building on historical data for inflow, storage, and release, an interpretable, threshold-based decision framework was developed and coupled with 14-day ensemble inflow forecasts from the California-Nevada River Forecast Center’s …

Novel Respirometry Measurement And Comparison Of Monod Kinetic Constants And Methanogen Concentrations For 27 Full-Scale Anaerobic Bioreactors, Nicholas Benn, Antonio Martins, Daniel H. Zitomer

Civil and Environmental Engineering Faculty Research and Publications

Monod kinetic coefficient values (km and Ks) as well as methanogen concentrations (Xac and Xh2) for various anaerobic bioreactors are required to gain a deeper understanding of anaerobic biotechnology. However, there are no existing, practical methods to measure or estimate these parameters or variables in typical anaerobic digester biomass that contains mixed cultures with inert organic solids. Current measurement methods rely on pure cultures developed in the laboratory. In this work, a novel respirometric method was developed and used to determine methanogen Monod parameters and active biomass concentration for samples from 27 full-scale anaerobic reactors. Differences (one to three orders …

Satellite Radar Imagery Analysis For Ground Hazard Risk Monitoring In Railway Tracks And Slopes, Sumanth Varma Byrraju

Theses and Dissertations

Railway transportation is essential to national economies globally, and disruptions from geohazards can result in significant operational delays and considerable economic consequences. Satellite radar technologies, including Interferometric Synthetic Aperture Radar (InSAR), offer an effective means to monitor geohazard risks across extensive railway networks. This thesis employs Multi-Temporal InSAR (MTInSAR) techniques, including Persistent Scatterer InSAR (PSInSAR) and Small Baseline Subset (SBAS), to identify high-risk areas along railway rights of way (ROW) prior to geohazard occurrences. However, the efficiency of these MT-InSAR and, consequently, the caliber of the data generated may be restricted by elements like topographical profile, vegetation, and surface soil …

Evaluation Of Waste Plastic Addition Via Dry Method On Asphalt Mixture Performance, Isabella Madeira Bueno

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Incorporating waste plastic (WP) into hot mix asphalt (HMA) offers a promising approach to enhance recycling rates and improve asphalt concrete (AC) performance, particularly in moisture damage resistance. However, results vary widely due to differences in WP types, sizes, and mixing methods. The lack of standardized procedures, especially for the dry process, has led to inconsistent integration and unclear roles of WP in AC mixtures. Studies suggest that introducing WP to pre-heated aggregates at temperatures exceeding its melting point can enhance mixture resistance to rutting, cracking, and moisture damage. In this context, this study was conducted in two phases to …

A Review On The Use Of Salt And Sugar As Natural Admixtures In Concrete, Noura A. Yassine, Lelian W. Elkhatib, Adel Elkordi, Mohammed Sonebi, Jamal Khatib

BAU Journal - Science and Technology

Due to the large increase in construction nowadays, the focus on the reduction of waste in the environment and saving cost becomes crucial. This issue, if solved, will conserve natural materials and make an eco-friendly environment. According to this, the use of natural materials, specifically in concrete/mortar, will shape a green and sustainable environment. One of the most used materials in construction is concrete where some additives like accelerators and retarders are added in order to enhance and modify some properties of concrete. These additives are beneficial and important to be used specifically in case of different weather conditions. Weather …