Civil and Environmental Engineering Commons^™

Mechanical Properties And Microstructural Characteristics Of Hydrated Bcsa Cement At Extreme Temperatures, Behzad Farivar

Graduate Theses and Dissertations

Belitic Calcium Sulfoaluminate (BCSA) cement is an alternative binder known for its rapid setting and high early strength, making it ideal for applications such as fast-track construction and repair. This study presents a comprehensive investigation into the behavior of BCSA cement under a wide range of curing temperatures, with emphasis on early-age strength development, admixture effects, and the use of the maturity method for strength prediction.

The research evaluates BCSA cement performance in both hot and cold environments, ranging from approximately -28.9 °C (-20°F) to 49 °C (120°F). In warm climates, citric acid was used as a set retarder to …

Development Of Soil Water Characteristic Curves Through Control Of Relative Humidity, Lauren E. Johnson, Julia I. Loshelder, Richard A. Coffman

Civil Engineering Undergraduate Honors Theses

The relationship between soil suction and soil water content in unsaturated soil mechanics is important but can be difficult to measure. The objective of the research described herein was to develop soil water characteristic curves (SWCC) from relative humidity values by incorporating the use of glycerin-water mixtures. Glycerin-water mixtures can be used to achieve different relative humidity levels by varying the concentration of glycerin within the mixture. The relative humidity created by each mixture was measured with a relative humidity sensor, and the relative humidity values and Kelvin’s equation were used to compute the total suction.

Soil water characteristic curves …

Relating Strength, Time, And Temperature For Bcsa Cement Concrete Using The Maturity Method, Daniel M. Passarelli

Civil Engineering Undergraduate Honors Theses

Belite calcium sulfoaluminate (BCSA) cement is an extension of CSA cement technology designed to provide early setting times and rates of strength gain with reduced environmental impact compared with portland cement. However, its application in the field of structural concrete is widely unexplored. To that end, this paper details research conducted at the University of Arkansas Civil Engineering Research and Education Center (CEREC) exploring the rates of strength gain in concrete samples created using BCSA cement relative to various temperatures and ages. Following the practices outlined in ASTM C1074, the maturity method, compression strength tests were conducted on the aforementioned …

Experimental Study Of Novel Bcsa Scc Repair Materials And Implications On Corrosion In Bcsa Concrete Structures, Elizabeth S.M. Poblete

Graduate Theses and Dissertations

Some current building codes for structural concrete allow the use of alternative cement concrete if their structural, durability, and fire performance can be shown to be comparable to portland cement (PC) concrete. One such alternative cement, belitic calcium sulfoaluminate (BCSA) cement, is a promising standalone replacement for portland cement given its lower global warming potential (GWP), fast setting time, and high early age compressive strength. These properties also make it an ideal repair material. But repair materials often need to be highly flowable and easy to consolidate and their performance when used to repair PC concrete structures must be understood. …

Subsurface Characterization Using Electrical Resistivity Tomography (Ert) Integrated With Masw, P-Wave Refraction, And Boring Results, Mohammadyar Rahimi

Graduate Theses and Dissertations

Electrical resistivity tomography (ERT) has gained widespread application in geotechnical engineering as a non-invasive method for subsurface characterization. Despite its versatility, several challenges remain regarding its resolution capabilities, interpretive limitations, and integration with other investigative methods. This dissertation addresses three key applications of ERT, focusing on its effectiveness and limitations in resolving thin subsurface layers, detecting anomalies such as voids, and supporting environmental assessment in river restoration projects.

The first study investigates the ability of ERT to resolve thin, discontinuous clay layers beneath levees, using the Melvin Price Reach of the Wood River Levee on the Mississippi River as a …

Feasibility Of Liquid Carbon Sources For Algae Growth, Brady S. Jones

Chemical Engineering Undergraduate Honors Theses

This thesis explores the use of electrochemically produced aqueous bicarbonate as a novel liquid-phase carbon source for enhancing algal biomass productivity. Targeting the freshwater microalgae Chlorella Saccharophila, the study investigates its growth response to varying bicarbonate concentrations and compares the efficacy of liquid bicarbonate delivery with traditional gaseous CO₂ bubbling methods. Results demonstrate that Chlorella Saccharophila can sustain growth solely on bicarbonate, and that bicarbonate-fed cultures yielded higher biomass than those supplied with gaseous CO₂ or hybrid systems. These findings validate the potential of bicarbonate-based carbon delivery for scalable algae cultivation, offering key advantages such as gas-free operation, improved …

Enhancing Asphalt Mix Design Through Film Thickness And Bailey’S Gradation Method, Lydia Quinn

Civil Engineering Undergraduate Honors Theses

Contemporary asphalt research aims to strike a balance between rutting and fatigue cracking to enhance pavement longevity. The performance of asphalt mixtures is influenced by factors such as aggregate gradation and asphalt film thickness. Although gradation typically adheres to the mid-gradation method, asphalt film thickness is included in certain mix designs, even though it is not universally regarded as an essential parameter. Nonetheless, no current method primarily addresses both gradation and asphalt film thickness together. In this research, aggregate gradations were designed using the principles of Bailey’s method along with various other criteria such as control points, the dust to …

A Statistical Investigation Of The Parameters Influencing Rutting And Cracking Performance In Asphalt Mixtures, Alexis Light

Civil Engineering Undergraduate Honors Theses

Durable pavement is essential for modern transportation infrastructure, especially in the United States of America which boasts over 8.5 million lane miles of roads and highways. Despite advanced construction techniques, asphalt pavements are susceptible to rutting and cracking, significantly affecting their performance and maintenance costs. Current methods for analyzing rutting and cracking in asphalt mixtures rely on various parameters, leading to measurement variability. This highlights the need for more rigorous analysis to explore the relationship between mix design variables and pavement performance. This research explores the IDEAL-CT and APA data from 171 mix designs collected by the Arkansas Department of …

Assessing The Fate Of Antibiotic Resistance Genes In Wastewater Treatment Processes, Gunter A. Campbell

Civil Engineering Undergraduate Honors Theses

The increasing need for clean water has paved the way for the creation of systems for reusing water, such as wastewater treatment plants (“WWTPs”), to provide potable water. But in recent years, such systems have raised concerns about the distribution of antibiotic resistance genes (“ARGs”). Bacteria are adapting to antibiotics by the evolution of resistance mechanisms, such as high mutation rates and horizontal transfer. The presence of ARGs, particularly tetracycline ("tetA") resistance genes, in wastewater effluents is of concern, as they can survive treatment, spread to bodies of water, and pose a threat to human health. In this study, the …

Establishing Particle Size Recommendations For Cationic Asphalt Emulsions, Tanner Turben, Pedro Diaz-Romero, Andrew Braham

Civil Engineering Faculty Publications and Presentations

Asphalt emulsions are used in flexible pavement maintenance and rehabilitation treatments. Emulsion specifications for material characterization are based on testing methodology dating to the 1930s. Newer test methods, including particle size analysis (PSA) of binder droplets in emulsion, have been explored but not implemented into specifications. The objective of this study is to observe the particle size and performance of cationic slow-setting (CSS) emulsions and establish baseline particle size recommendations for cationic emulsions. Four physical property tests (residue, oversize particles, viscosity, and particle size) and two cold mix asphalt performance tests (indirect tensile strength (IDT) and direct shear test (DST)) …

Workforce Forecasting For State Transportation Agencies: A Machine Learning Approach, Adedolapo Ogungbire, Suman Mitra

Civil Engineering Faculty Publications and Presentations

A decline in the number of construction engineers and inspectors at state transportation agencies (STAs) to manage the ever-increasing lane miles has emphasized the importance of workforce planning in these agencies. Forecasting workforce requirements is crucial for effective planning in any industry or agency. This study developed machine learning (ML) models to estimate the person-hour requirements of STAs at the project level. The Arkansas Department of Transportation (ARDOT) was used as a case study, using its employee and project details data between 2012 and 2021. ML regression models ranging from linear, tree ensembles, kernel-based, and neural network-based models were …

Workforce Forecasting For State Transportation Agencies: A Machine Learning Approach, Adedolapo Ogungbire, Suman Kumar Mitra

Civil Engineering Faculty Publications and Presentations

A decline in the number of construction engineers and inspectors at state transportation agencies (STAs) to manage the ever-increasing lane miles has emphasized the importance of workforce planning in these agencies. Forecasting workforce requirements is crucial for effective planning in any industry or agency. This study developed machine learning (ML) models to estimate the person-hour requirements of STAs at the project level. The Arkansas Department of Transportation (ARDOT) was used as a case study, using its employee and project details data between 2012 and 2021. ML regression models ranging from linear, tree ensembles, kernel-based, and neural network-based models were …

Examining The Impact Of The Covid-19 Pandemic On Older Adults' Activity Participation And Mode Usage In A Rural State: A Case Study Of Arkansas, Arna Nishita Nithila, Suman Kumar Mitra, Alishia Juanelle Ferguson, Michelle Gray, Jennifer D. Webb

Civil Engineering Faculty Publications and Presentations

The objective of the study was to investigate the impact of the COVID-19 pandemic on the activity participation and mode usage of older adults residing in Arkansas, a predominantly rural state. Leveraging primary data collected from 832 older adult participants, the study employed Latent Class Analysis (LCA) to capture older adults' heterogeneity in travel behavior and found three distinct classes: Pandemic-affected minimal travelers, Unaffected non-commuter car users, and Unaffected commuter car users, showing different levels of their activity participation, mode usage during the pandemic and varying the pandemic's impact on their trips. To understand these variations in light of the …

A Multi-Method Geophysical Approach For Complex Shallow Landslide Characterization, Mohammadyar Rahimi, Clinton Wood, Meersad Fathizadeh, Salman Rahimi

Civil Engineering Faculty Publications and Presentations

This case study demonstrates the value of combining multiple non-invasive geophysical methods to characterize a landslide along Highway 7 near Jasper, Arkansas, USA. Geophysical testing was conducted using Multichannel Analysis of Surface Waves (MASW), Horizontal to Vertical Spectral Ratio (HVSR), and Electrical Resistivity Tomography (ERT), supplemented by select soil borings. The geophysical investigation aimed to provide a high-resolution, near-continuous view of subsurface conditions, including bedrock depth and the location of the groundwater table or highly saturated zones within the slide area. These factors are important contributors to slope instability. The MASW results revealed a highly variable depth to weathered bedrock …

Assessing The Effect Of Material Properties On Full Depth Reclamation (Fdr) Mixtures Via Compressive Strength Characterization, Toluwanimi Ogundipe

Graduate Theses and Dissertations

Enormous amounts of money to replace all poorly maintained roads with brand new construction or with rehabilitation options like the mill and overlay which neglects the address of underlying pavement issues. To reduce the cost intensity of new construction of dilapidated pavements, state departments of transportation are seeking cost-effective techniques to rehabilitate roads. One of the techniques that have been explored and implemented by state DOTs is full-depth reclamation. Full depth reclamation (FDR) as a pavement rehabilitation technique is the reclaiming and recycling of an existing pavement with a predetermined amount of existing base layer. The combination of the reclaimed …

Controlling Expansion Behavior Through Curing And Mix Design For An Expansive, Rapid-Setting Bcsa Cement, Amanda Parolini Dutra

Graduate Theses and Dissertations

Cracking in concrete has been a concern for engineers because it reduces its durability and strength. Some of this cracking behavior is due to shrinkage, which occurs when the water in the concrete evaporates and causes a reduction in volume. Expansive cements were invented to counteract this shrinkage behavior. This research studies a new formulation of a standalone, fast-setting, fast-strength gain expansive BCSA cement. Since it is a new cement, a limited amount of literature is available about mixture design, strength properties, and how to obtain the desired level of expansion. This study then aims to fill some of these …

Determination Of The Internal Erosion Potential Of Bcsa Soil-Cement Using A Modified Hole Erosion Test System, Edgar Enrique Ortega De La Cruz

Graduate Theses and Dissertations

Levees play a fundamental role in preserving human lives and resources and are the key infrastructure protecting against flood events. In the United States, the levee system is extensive, but unfortunately many of the levees were either not engineered or have well exceeded their intended design life. This was evident after the Midwest floods of 2019, which resulted in the failure of multiple levees leading to costly losses and repairs. In addition, flood levels remained high for days at a time, making it imperative to find fast and effective repair methods. This thesis presents a study conducted at the University …

Paste Properties, Hardened Concrete Properties, And Mix Design Process For Magnesium Phosphate Cement, Rilye Dillard

Graduate Theses and Dissertations

Magnesium phosphate cement (MPC) is a rapid-setting alternative cement typically used as a quick repair material. MPC has gained popularity in recent years due to its ability to reduce CO2 emissions, its strong chemical resistance, and potential use in large scale applications. There is currently limited research on the properties of MPC when varying the proportions of its ingredients. Several hardened concrete properties were analyzed on concrete mixtures made with MPC. A mix design process for MPC concrete is proposed based on testing of 300 MPC paste mixtures and 115 MPC concrete mixtures. A standardized mix design process is imperative …

An Investigation Into The Effect Of Performance Engineered Mixture (Pem) Design On The Workability And Strength Of Concrete Pavement Mixtures, Alexander Cook

Graduate Theses and Dissertations

The Arkansas Department of Transportation (ARDOT) currently requires a minimum cement content of 564 pounds of cement per cubic yard of concrete. This minimum cement requirement can be reduced through the utilization of optimized gradation of aggregates within concrete mixtures as well as the addition of supplementary cementitious materials (SCMs) such as fly ash. The study presented in this paper aims to demonstrate how the use of the Tarantula Curve can be used to design concrete mixtures with reduced cement contents while maintaining sufficient workability for concrete mixtures to be used for slipform paving. Fresh workability was measured using the …

Cytotoxicity And Genotoxicity Of Glyphosate And Roundup Quickpro On Chinese Hamster Ovary Cells, Tasnimul Ferdous

Graduate Theses and Dissertations

Glyphosate and Roundup products have become the most used herbicide worldwide. However, previous bans in Europe and recent reversal have caused confusion over their safety. This study aims to investigate the cytotoxic and genotoxic effects of Roundup QuickPro and its main ingredient glyphosate using Chinese hamster ovary (CHO) cells. Cytotoxicity was calculated by measuring CHO cell viability with 72 hours of exposure to each toxicant. Roundup exhibited higher cytotoxicity with LC50 of 511.2 μg/mL than glyphosate’s LC50 of 3389 μg/mL. The recommended application concentration (11,233.7 μg/mL) of Roundup QuickPro is much higher than the measured LC50, which caused complete cell …

Partnering With Communities To Understand Social Determinants Of Health (Sdoh) Impacts On Access To Shared Micromobility, Elizabeth K. Mcclain, Kaitlynn Walker, Ganesh Kumar, Ashley Bright, Clare Aziz, Ann W. Banchoff, Zacharia N. Doueiri, Abby C. King, Suman Mitra

Civil Engineering Faculty Publications and Presentations

This study explored the facilitators and barriers of community bike share use in a mid-sized city with high incidence of poverty and racial diversity using a community-based participatory action research (CBPAR) photovoice framework with the Stanford Our Voice (OV) Discovery Tool digital application. Community members participated in one of three community citizen science walks with follow up focus groups facilitated by osteopathic medical student researcher to address “What makes it easy or hard to ride a bike using the bike share?” Twenty-seven diverse community members partnered with four osteopathic medical students exploring vulnerable individuals’ lived experiences, beliefs/understanding of the Social …

Unlocking Telecommuting Patterns Before, During, And After The Covid-19 Pandemic: An Explainable Ai-Driven Study, Adedolapo Ogungbire, Suman Kumar Mitra

Civil Engineering Faculty Publications and Presentations

The COVID-19 pandemic has instigated a global paradigm shift in employment practices, precipitating a widespread transition to telework. While past events had no long-lasting effect on the continued working conditions of the population, it is unclear what a prolonged need for telecommuting on such a nationwide scale would continue to have on the working population. This study uses an explainable artificial intelligence approach to investigate the changes in those telecommuting across three periods: i) pre-pandemic, ii) pandemic, and iii) post-pandemic periods. Machine learning methods, including decision trees, random forest, extreme gradient boost, naïve Bayes, and artificial neural networks, were developed …

Estimation Of Cement Paste Stiffness And Uhpc Elastic Modulus Through Measured Phase-Property Upscaling, Charissa N. Puttbach, Gary S. Prinz, Cameron D. Murray

Civil Engineering Faculty Publications and Presentations

The elastic stiffness of bulk concrete materials results from the complex interaction of aggregates, voids, and hydrated cement (which can have multiple hardened phases at multiple length scales). Given the complexities associated with understanding the arrangement of these particles within bulk concrete volumes, estimations for elastic modulus often rely on empirical correlations with unit weight and compressive strength. Such estimations are inherently scale-dependent and fail to capture variability in mix designs, particularly the variability found in specialty concrete mixes. To develop a scale-independent method for estimating elastic modulus from mix-design volume fraction information, this study explores a novel …

Quantifying Lock Criticality For Inland Waterway Navigation Using An Agent-Based Simulation, Ashwin Narayan

Industrial Engineering Undergraduate Honors Theses

Inland waterway travel has tremendous potential to improve multimodal transportation in the United States due to its environment-friendly and safe nature. Waterway travel has proven to be much cheaper per ton-mile and more fuel efficient than trucks. Millions of dollars have recently been invested in inland waterway networks to facilitate travel. The waterway infrastructure must be resilient to enable efficient waterway travel and prevent unnecessary delays. Locks, an important component of waterway infrastructure, enable vessels to travel between waterways of varying depths and must be maintained consistently to avoid unexpected failures. However, with limited resources, it is difficult to preserve …

Batch And Placement Size Effects On The Setting Time Of Bcsa Cement Concrete, Micaiah Rivers

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate cement (BCSA) is an alternative to portland cement which offers numerous benefits due to its rapid-setting behavior and sustainability properties. BCSA cement concrete has many potential applications, particularly for structural and transportation infrastructure repair. Due to the rapid-setting properties of BCSA cement, a comprehensive understanding of the setting process is critical for efficient and effective use of this material. The primary objective of this research was to determine the effects of mixture size on the setting time and temperature behavior of BCSA cement concrete, and to investigate the relationship between initial set time and workability. Using a …

An Investigation Of The Effect Of Performance Engineered Mixture (Pem) Design On Durability And Air Void Matrix Of Concrete Pavements, Jacob Ortlieb

Graduate Theses and Dissertations

Performance Engineered Mixture (PEM) design is a novel method of creating concrete pavement that is economical achieving desirable performance properties such as durability, strength, and workability. Performance-based design is critical for concrete pavements, so the fresh concrete can be placed without issue and the hardened concrete can withstand deterioration and environmental damage such as freezing and thawing. To achieve economical concrete, PEM utilizes tools such as the tarantula curve for aggregate grading, and the Super Air Meter (SAM) test, providing information regarding the air void matrix while the concrete is fresh. To achieve these properties with less cement will lead …

Development Of An Innovative Rapidly Constructible Bridge, Swikar N. Pyakurel

Graduate Theses and Dissertations

Rapidly deployable temporary bridges are critical for military operations in hostile environments. The research focuses on conceptualizing bridge solutions for MLC 40 loading and 30 feet span that can be operational within hours, require minimal personnel and equipment, and are compact for logistics. An extensive literature review covered historic deployable structures, retractable stadium roofs, structures in aerospace, permanent deployable bridges, current military bridges, innovative deck solutions, lightweight structural materials, and compliant mechanisms. The study then investigated bridge superstructures made of lightweight Aluminum 6061-T6 alloy utilizing tensegrity and prefabricated aluminum extruded decks to meet the criteria. Two concepts, expandable scissor truss …

Impact Of Equipment Type On Measured Particle Size Of Civil Engineering Materials, Tanner Turben

Graduate Theses and Dissertations

Particle size analysis (PSA) captures the size distribution of fine-grained or emulsified materials with particles generally smaller than 1000 microns. Asphalt emulsions and many other civil engineering materials do not leverage PSA for material specifications or acceptance despite the insight into material performance and quality gained through understanding the particle size. The objectives of this study are to compare PSA measurement principles by testing 13 civil engineering materials by laser diffraction, Coulter counter, and microscopy and to develop a draft standard procedure for asphalt emulsion PSA. Asphalt emulsions, cementitious materials, sands, clays, and biological samples were selected to represent a …

Identifying Waterway Traffic Flow Patterns Using Modified Clustering, Shihao Pang

Graduate Theses and Dissertations

Efficient management of inland waterways is essential for the economic and operational efficiency of transportation networks. Characterization and prediction of waterway vessel traffic flow patterns by time of day are critical for optimizing planned disruptive events like maintenance activities. This study identifies and predicts inland waterway traffic flow patterns along the Lower Mississippi River (LMR) using a modified clustering approach. A five-year period of Automatic Identification System (AIS) data, which tracks vessel movements in real-time, is used for model development and evaluation. The model first segments the river into approximately one-mile-long traffic message channels (TMCs) to estimate vessel counts and …

Applying Uas Lidar For Developing Small Project Terrain Models, Ashraf Siddiqui

Graduate Theses and Dissertations

Unmanned aerial systems (UAS) LiDAR was used to collect survey data for small-area projects, particularly bridge replacement projects. The project aimed to compare UAS LiDAR data with conventional surveying methods. For the project, five bridge sites were selected for UAS LiDAR and conventional survey data collection, which include Lincoln Bridge 1 (East), Lincoln Bridge 2 (West), Humnoke, Frenchman’s Bayou, and Mountain Home. Data for each site was collected during the 2021–2022 winter. A DJI M600 Pro and Phoenix LiDAR Systems AL3-16 LiDAR unit were used for the UAS LiDAR measurements. The conventional survey equipment used included a global navigation satellite …