Civil Engineering Commons^™

Load And Pressure Distribution As A Function Of Dynamic Contact Stress At The Railroad Crosstie-Ballast Interface, Habib Abdil Unluoglu

Theses and Dissertations--Civil Engineering

Excessive crosstie wear and abrasion and ballast wear and fouling are two of the fundamental problems contributing to inadequate railroad track performance. This adversely affects the attainment and long-term maintenance of desired track geometric requirements. The magnitudes and distribution of the stresses at the crosstie-ballast (CT-B) interface must be known to determine the stress distribution on the ballast. However, the stresses at the top of the ballast often vary significantly. This study examines a new approach to predicting dynamic contact pressures at the interface of crosstie and ballast using the ‘square wave theory.’ A data set of in-track CT-B interfacial …

Understanding The Differences Between Industry Objectives And Institutional Learning, Kristen Schell

Theses and Dissertations--Civil Engineering

To combat understaffing in the construction industry, it is necessary to employ the best candidates possible. By identifying the most desirable skills in a construction employee from an industry perspective, institutional learning can better prepare graduates for the construction workforce. Currently there exists an information gap in the objectives of the construction industry and institutional learning. This gap produces graduates, professors, and employers with expectations that do not align. Reducing this gap will aid in the success of hiring recently graduated construction students who can meet the ever-changing demands of the industry. Construction students who are fresh out of college …

Using Stream Restoration To Mitigate Stormwater Runoff In An Urban Watershed: A Case Study, Jonathan M. Brantley

Theses and Dissertations--Biosystems and Agricultural Engineering

The goal of this case study was to evaluate the effectiveness a 275 m regenerative stream restoration design to mitigate stormwater runoff in a highly urbanized watershed. The restoration resulted in a wide, wetland-like floodplain, comprised of a rock base that was overtopped with a filtration media (approximately 30% woodchips and 70% topsoil). The creation of the floodplain-wetland complex in tandem with filtration media lead to increased storage capacity and an increase in hyporheic exchange within the system. Significant reductions were found for the storm hydrograph parameters volume, peak discharge, and time to peak. Reductions in baseflows were also noted …

Propositions For A Resilient, Post-Covid-19 Future For The Aec Industry, Hala Nassereddine, Kyung Wook Seo, Zofia K. Rybkowski, Christian Schranz, Harald Urban

Civil Engineering Faculty Publications

The coronavirus outbreak has challenged and continues to challenge every aspect of the supply chain within the AEC industry, forcing stakeholders to cope with increasing uncertainties and continuous change. The notion of resilience is especially salient now. While the need for the AEC industry to focus on resilience has been highlighted in recent articles, there is a need for a comprehensive discussion on what resilience means for the AEC industry and how companies can create built-in resilience. This paper takes the form of a high-level overview of where the industry is headed and aims to establish eleven propositions for a …

Impact Of Preferential Flow, Source Water Connectivity, And Agricultural Management Practices On Sediment And Particulate Phosphorus Dynamics In Midwestern Tile-Drained Landscapes, Saeid Nazari

Theses and Dissertations--Biosystems and Agricultural Engineering

Tile drainage is recognized as a significant transporter of sediment and particulate phosphorus (PP) in the Midwestern U.S., leading to proliferation of Harmful Algal Blooms (HABs). Numerous studies have focused on Dissolved Reactive Phosphorus (DRP) and Nitrogen (N) flux dynamics in tile-drained landscapes; however, the impact of preferential flow and agricultural management practices on fate and transport of sediment and PP has remained poorly understood. The overarching objective of this study was to improve understanding of sediment P delivery in tile-drained landscapes. This dissertation focuses on four studies. In the first study, forms and flow pathway dynamics of total phosphorus …

Evaluation Of Liquid Ice Melting Additives For Winter Maintenance Applications, Erin Lammers-Staats

Theses and Dissertations--Civil Engineering

Winter weather can often pose difficulties for transportation agencies as they work to clear roads of snow and ice quickly so that motorists can travel safely and efficiently. Kentucky has made efforts to maximize efficiency within its winter maintenance program by focusing on optimized equipment usage and personnel time management. This study’s objective was to evaluate novel anti-icers and calculate how their performance compared to the current performance of brine and calcium chloride mixture. New brine additives claim to offer better results, but there is very little guidance about how to systematically evaluate new anti-icers. The author developed a testing …

Geophysical Techniques Used For The Analysis And Prediction Of Soil Strength And Mechanical Behavior, Matthew A. Hurley

Theses and Dissertations--Civil Engineering

Determining soil properties involves extensive laboratory testing of samples at discrete timing and location. Non-destructive analysis methods, such as electrical and seismic, presents alternatives to means of gathering soil properties accompanied with increased flexibility due to spatial and temporal applications. This research examined the ability of seismic wave data to predict soil behavior such as stress-strain and pore pressures using a modified version of Duncan and Chang (1970). Friction angle predictions were also analyzed using shear wave velocity and a modified form of the Santos and Gomez-Correria (2001) equation. This research also analyzed the use of electrical data to predict …

Life Cycle Assessment Of Polylactic Acid Biopolymer Industrial Waste Management Techniques In Belize, Dennis J. Newby

Theses and Dissertations--Civil Engineering

In January 2020, the Government of Belize enacted an Implementation Strategy and Action Plan to phase-out single-use plastics and to transition to products like bioplastics. This work investigated the environmental effects of using alternative waste management techniques to manage polylactic acid biopolymer (PLA) waste by using life cycle assessment (LCA). The following treatment options were compared: landfill, landfill expansion, cogeneration, and anaerobic digestion. The landfill and landfill expansion processes both had a global warming potential of 0.01 kg of CO₂ eq. per kg of PLA waste managed compared to the cogeneration and anaerobic digestion processes -0.03 and -0.06 kg …

Assessing Freeway Crash Risk Using Crowdsourced Waze Incident Alerts, Eugene Boasiako Antwi

Theses and Dissertations--Civil Engineering

Traffic data obtained through crowdsourcing are becoming more accessible to traffic agencies due to advancements in smartphone technology. Traffic managers aim to use this data to complement their conventional sources of data and provide additional context in their analysis. In this study, Waze incident alerts are integrated with GPS-Probe speed data and Kentucky State Police (KSP) crashes to assess their impact on traffic flow and safety on freeways in Kentucky. The analysis showed that the presence of a vehicle on the shoulder is associated with about 36.7% of freeway crashes in Kentucky. The presence of a vehicle on the shoulder …

Investigation Of Nitrate Transfer In Karst Basins During Storm Events Using Submersible Underwater Nutrient Analyzers, John Pike

Theses and Dissertations--Civil Engineering

Knowledge of nitrate sources and pathways in karst basins remains incomplete and hinders management of nutrients that cause algae blooms and degrade municipal water supply. However, the increased availability of optical, ultraviolet nitrate sensors allows advancement of nitrate source and transfer for water managers. A concept model is hypothesized for nitrate transfer during hydrologic events and baseflow that considers the multiple porosity of karst. To test the concept model, 15-minute nitrate sensor data is collected with submersible underwater nutrient analyzers over a multi-year period from two locations in a karst basin in the inner bluegrass region of central Kentucky, USA. …

Localization Of Stationary Source Of Floor Vibration Using The Steered Response Power Method, Mohammad Royvaran

Theses and Dissertations--Civil Engineering

If the generated vibration in a building exceeds the acceptable limit design for a floor system, it is necessary to identify the source of vibration, a process known as localization. The objective of this study is the localization of stationary vibration sources, and the approach used is the steered response power (SRP) method. This method has already been shown to work well for wireless and acoustical applications to locate transmitter and sound sources, respectively. To the writer’s knowledge, this study is the first application of the SRP method to locate vibration sources using floor vibration measurements. However, because waves behave …

Landslide Site Assessment And Characterization Using Remote Sensing Techniques, Batmyagmar Dashbold

Theses and Dissertations--Civil Engineering

Landslides are common and dangerous natural hazards that occur worldwide, often causing severe direct impacts on human lives, public and private properties. It is imperative to identify the landslide susceptible areas to avoid or mitigate the possible damage. Landslide prediction can be presented in a slope failure in spatial and/ or temporal terms. If it is presented in spatial term, it is considered a landslide susceptibility map (LSM) defined as the probability of spatial occurrence of slope failures. If it is presented in a combination of spatial and temporal distribution of the landslide susceptibility, it is commonly referred to as …

Artificial Intelligence And Soft Computing In Smart Structural Systems, Sajad Javadinasab Hormozabad

Theses and Dissertations--Civil Engineering

Next-generation smart cities are the key feature in the next chapter of human life. Cities that employ innovative and technology-driven solutions to improve the sustainability, resilience, prosperity, and amenity of the community are considered smart cities. Development of smart cities requires fundamental innovations in many technical and technological aspects including those contributing to smart structures. Smart technologies improve the structural performance against natural disasters like earthquakes, hurricanes, tornados, and promote the sustainability of structural systems. Next-generation smart structures encompass a variety of technologies including Structural Control (SC) and Structural Health Monitoring (SHM). SC covers methodologies and technologies that modify the …

Quantifying The Source And Pathway Of Dissolved Reactive Phosphate In Karst Drainage Of The Inner-Bluegrass, Cory Radcliff

Theses and Dissertations--Biosystems and Agricultural Engineering

In the Midwestern U.S. seasonal hypoxia experienced in the Gulf of Mexico and harmful algal blooms in inland freshwater ponds, lakes, and rivers are partly fueled by dissolved orthophosphate loadings from disturbed landscapes. Efforts to reduce dissolved reactive phosphate (DRP) loadings have had varying levels of success and have led to insufficient water quality improvements. Inefficiencies in conservation strategies can stem from poor understanding of phosphate source and flow pathway dynamics. This study focused on monitoring sources and flow pathways of dissolved reactive P in a karst agroecosystem with phosphatic limestone. We collected event water samples at the Camden Creek …

Recent Shrinkage And Fragmentation Of Bluegrass Landscape In Kentucky, Bo Tao, Yanjun Yang, Jia Yang, S. Ray Smith, James F. Fox, Alex C. Ruane, Jinze Liu, Wei Ren

Plant and Soil Sciences Faculty Publications

The Bluegrass Region is an area in north-central Kentucky with unique natural and cultural significance, which possesses some of the most fertile soils in the world. Over recent decades, land use and land cover changes have threatened the protection of the unique natural, scenic, and historic resources in this region. In this study, we applied a fragmentation model and a set of landscape metrics together with the satellite-derived USDA Cropland Data Layer to examine the shrinkage and fragmentation of grassland in the Bluegrass Region, Kentucky during 2008–2018. Our results showed that recent land use change across the Bluegrass Region is …

Holistic Resilience Quantification Framework Of Rural Communities, Amanda Melendez

Theses and Dissertations--Civil Engineering

Communities need to prepare for anticipated hazards, adapt to varying conditions, and resist and recover rapidly from disturbances. Protecting the built environment from natural and man-made hazards and understanding the impact of these hazards helps allocate resources efficiently. Recently, an indicator-based and time-dependent approach was developed for defining and measuring the functionality and disaster resilience continuously at the community level. This computational method uses seven dimensions that find qualitative characteristics and transforms them into quantitative measures. The proposed framework is used to study the resilience of rural communities’ subject to severe flooding events. Harlan County in the Appalachian region is …

Effect Of Socioeconomic And Demographic Factors Of Driver Residence On Crash Occurrence, Shraddha Sagar

Theses and Dissertations--Civil Engineering

In the U.S., road traffic crashes are a leading cause of death. Crash data from the state of Kentucky shows that the per capita crash rates and crash-related fatalities were higher than the national average for over a decade. In effort to explain why the U.S. Southeast experiences higher crash rates than other regions of the country, previous research has argued the region’s unique socioeconomic provide a compelling explanation. Taking this observation as a starting point, this study examines the relationship between highway safety and socioeconomic characteristics using an extensive crash dataset from Kentucky.

The primary goal of this research …

The Relationship Between Roadway Homogeneity And Network Coverage For Network Screening, Riana Tanzen

Theses and Dissertations--Civil Engineering

In the context of transportation safety engineering, network screening is a method of identifying and prioritizing high-risk locations for potential safety investment. Since its release, the Highway Safety Manual (HSM) has facilitated the adoption of Safety Performance Functions (SPF) to predict the number of crashes for the network screening of any facility type. The predictive model becomes more reliable when developed from crash data with homogeneous roadway segments and this homogeneity can be attained by applying specific geometric attributes to the dataset. The caveat to this method is the requirement of adjustment factors (AFs) to adjust the predicted estimate for …

Fluvial Sediment Organic Matter Degradation Identified With Elemental And Isotopic Fate During Laboratory Incubation, Brenden Riddle

Theses and Dissertations--Civil Engineering

Fluvial sediment is well recognized as a critical factor in both carbon and nutrient budgets within stream systems. However, we find very few studies of reactivity and isotope enrichment for stream water from agricultural and urban streams and the class of substrate known as fluvial sediment organic matter. This study investigated the hypothesis that fluvial sediment is subject to degradation even though many previous studies have considered this class of substrate generally inert. Therefore we qualify that elemental and isotopic signatures of fluvial sediment organic matter should be considered potentially non-conservative when used in tracer studies. Methods applied to this …

Adaptive Tracking Controller For Real-Time Hybrid Simulation, Alejandro Palacio-Betancur

Theses and Dissertations--Civil Engineering

Real-time hybrid simulation (RTHS) is a versatile and cost-effective testing method for studying the performance of structures subjected to dynamic loading. RTHS decomposes a structure into partitioned physical and numerical sub-structures that are coupled together through actuation systems. The sub-structuring approach is particularly attractive for studying large-scale problems since it allows for setting up large-scale structures with thousands of degrees of freedom in numerical simulations while specific components can be studied experimentally.The actuator dynamics generate an inevitable time delay in the overall system that affects the accuracy and stability of the simulation. Therefore, developing robust tracking control methodologies are necessary …

Probabilistic Approach To Water, Sediment, And Nutrient Connectivity For Advancing Watershed Modelling, David Tyler Mahoney

Theses and Dissertations--Civil Engineering

The goal of this dissertation is to represent the spatial and temporal domains of water, sediment, and nutrient flux and pathways within fluvial and watershed settings. To complete this goal, we integrate connectivity theory into watershed model structures to simulate water, sediment, and nutrient movement at the fundamental unit they occur. Fluvial-based sediment and nutrient flux is an important driver of global sediment and nutrient budgets, and the quantification of which serves as an ongoing challenge to limnologists, engineers, and watershed managers. Watershed models have been richly developed over the past century, but are currently restrained by problems related to …

A Modeling Approach To Understanding Glyphosate Transport In The Belize River Watershed, Barbara Anmei Astmann

Theses and Dissertations--Civil Engineering

Glyphosate is the most widely used herbicide worldwide and is often transported from application areas to surface water when solubilized in runoff or sorbed to eroded sediment. There is evidence that suggests both glyphosate and its main metabolite aminomethylphosphonic acid (AMPA) may pose a risk to human health, as well as cause adverse effects in the environment. However, consistent monitoring data is still limited, especially in developing countries. Belize is a developing nation with agriculture being a major sector of its economy and is heavily reliant on glyphosate. The widespread use of glyphosate in Belize may be resulting in glyphosate …

Design And Analysis Of A Pavement Marker Detection System, Timothy L. Johnson Ii

Theses and Dissertations--Civil Engineering

Personal injuries and property damage due to the failure of snow-plowable pavement markers which detach from pavement surfaces has led to the development of new all-plastic pavement markers which are located entirely below the planar surface of the pavement. The new all-plastic design pushes existing solutions used to avoid striping over highway reflectors into obsolescence since current solutions operate using electromagnets to sense the metal housings of snow-plowable pavement markers. A replacement solution is currently sought by the highway maintenance industry and three different marker detection methods were developed and tested on real-world highways with both new and aging pavement …

Variance Decomposition Of Forecasted Water Budget And Sediment Processes Under Changing Climate In Fluvial And Fluviokarst Systems, Nabil Al Aamery

Theses and Dissertations--Civil Engineering

Variance decomposition is the partitioning of different factors affecting the variance structure of a response variable. The present research focuses on future streamflow and sediment transport processes projections as the response variables. The authors propose using numerous climate factors and hydrological modeling factors that can cause any response variable to vary from historic to future conditions in any given watershed system. The climate modeling factors include global climate model, downscaling method, emission scenario, project phase, bias correction. The hydrological modeling factor includes hydrological model parametrization, and meteorological variable inclusion in the analysis. This research uses a wide spectrum of data, …

Reliability Assessment And Optimization Of Water Distribution Systems Explicitly Considering Isolation Valve Locations, Erika Hernandez Hernandez

Theses and Dissertations--Civil Engineering

Water distribution systems have changed the landscape of communities through two services: 1) providing water supply for domestic and industrial use, and 2) providing water required to fight fires. However, a substantial portion of the water infrastructure in the country, as many of other public assets built over 50 years ago, are now reaching the end of their useful life; which combined with rapid growth and changes in demographics have placed water distribution pipe networks at a state that requires revitalization. The aging infrastructure along with the growing threat of natural and man-made disruptions have led water utilities to place …

Image-Based Roadway Assessment Using Convolutional Neural Networks, Weilian Song

Theses and Dissertations--Computer Science

Road crashes are one of the main causes of death in the United States. To reduce the number of accidents, roadway assessment programs take a proactive approach, collecting data and identifying high-risk roads before crashes occur. However, the cost of data acquisition and manual annotation has restricted the effect of these programs. In this thesis, we propose methods to automate the task of roadway safety assessment using deep learning. Specifically, we trained convolutional neural networks on publicly available roadway images to predict safety-related metrics: the star rating score and free-flow speed. Inference speeds for our methods are mere milliseconds, enabling …

Analysis Of The Pile Load Tests At The Us 68/Ky 80 Bridge Over Kentucky Lake, Edward Lawson

Theses and Dissertations--Civil Engineering

Large diameter piles are widely used as foundations to support buildings, bridges, and other structures. As a result, it is critical for the field to have an optimized approach for quality control and efficiency purposes to measure the suggested number of load tests and the required measured capacities driven piles. In this thesis, an analysis of a load test program designed for proposed bridge replacements at Kentucky Lake is performed. It includes a detailed site exploration study with in-situ and laboratory testing. The pile load test program included monitoring of a steel H-pile and steel open ended pipe pile during …

Investigation Of Atmospheric Effects On Vapor Intrusion Processes Using Modelling Approaches, Elham Shirazi

Theses and Dissertations--Civil Engineering

Most people in the United States (US) spend considerable amount of time indoors—about 90% of their time as compared to outdoors, which makes the US population vulnerable to adverse health effects of indoor air contaminants. Volatile organic compound (VOC) concentrations are well-known to be higher in indoor air than outdoor air. One source of VOC concentrations in indoor air that has gained considerable attention in public health and environmental regulatory communities is vapor intrusion. Vapor intrusion is the process by which subsurface vapors enter indoor spaces from contaminated soil and groundwater. It has been documented to cause indoor air contamination …

E-Construction Technologies For Efficient Highway Construction Inspections, Dhaivat Patel

Theses and Dissertations--Civil Engineering

Over recent years, organizations such as the Federal Highway Administration and Departments of Transportation across the United States have showed interest in automating highway construction processes. The addition of e-Construction and other advanced technologies can significantly improve the efficiency and safety of highway paving operations, specifically paving inspections. Activities such as collecting load tickets, tracking pavement lay-down temperatures, and monitoring roller movement are antiquated practices that DOT inspectors perform during paving operations. E-Ticketing, Paver Mounted Thermal Profiling, and Intelligent Compaction were proposed to automate paving inspections and were recently tested in two resurfacing pilot projects in the state of Kentucky. …

Redefining Construction “As-Built” Plans To Meet Current Kentucky Transportation Cabinet Needs, Victoria Lynn Lasley

Theses and Dissertations--Civil Engineering

As-built drawings are the traditional method used by the construction industry to record changes made during construction. As-builts provide valuable information for new design projects as well as rehabilitation and remediation projects. The completeness and accuracy of these plans are essential for transportation industries and their success. While the importance of as-builts is widely recognized, the process of creating them has proven to be difficult. It is a time consuming process and entities often lack the resources necessary to complete accurate and detailed as-builts. After an investigation of current as-built operations within State Transportation Agencies, recommendations have been made to …