Engineering Commons^™

Uncertainty Quantification Of Live Load Effect In Buried Rc Box Culverts, Mohd Firoj

Dissertations and Theses

Although buried and mostly invisible to the traveling public, bridge-sized culverts (i.e., culverts with span around or longer than 20 ft) account for a large proportion of state-managed bridges. As per Oregon Department of Transportation inventory, there are approximately 35,000 culverts in the state highway system. Among them, 10,862 are in poor conditions and need to be analyzed for load rating purposes. The prediction and understanding of live load effects in culverts are crucial to the design, evaluation, and life-cycle maintenance of culverts. These live load effects include maximum bending moments and shear forces at different critical cross sections.

This …

Early-Age Strength And Failure Characteristics Of 3d Printable Polymer Concrete: Numerical Modelling And Experimental Testing, Mohammad Amin Dehghani Najvani

Civil Engineering ETDs

The time-dependent rheological and early-age strength parameters of Polymer concrete (PC) were investigated. PC flow decreased, and the static yield stress and thixotropy increased as the specimen aged, while the dynamic yield stress remained unchanged. The study found that the Herschel-Bulkley model can accurately describe the PC’s rheological behavior over time. The change in cohesion strength and internal friction angle over time was observed using uniaxial unconfined compression and direct shear tests of fresh PC. A time-dependent MohrCoulomb failure criterion was established. Temperature analysis was used to determine the gel time and explain the evolution of the time-dependent early-age strength …

Modeling Of Asphalt Concrete For Cross-Anisotropic Visco-Elasticity And Heterogeneity, Zafrul Hakim Khan

Civil Engineering ETDs

Asphalt Concrete (AC) is a cross-anisotropic viscoelastic material. This study has developed a methodology to backcalculate the cross-anisotropic properties of the AC layer from the Falling Weight Deflectometer (FWD) sensor and pavement response data from embedded sensors inside a pavement section. This study has also developed a two-way coupled Multiscale Finite Element Model (MsFEM) with Phase Field Fracture (PFF) to study the microstructural heterogeneity and damage of the AC layer based on the actual field loadings. A Finite Difference Time Domain (FDTD) and Machine learning-based backcalculation algorithm were developed to determine the layer thickness and dielectric constant from air-coupled Ground …

Analysis Of Loading Rate, Fiber Orientation And Material Composition Through Image Processing And Digital Volume Correlation In High Performance Concrete, Aidan R. Carlson

Electronic Theses and Dissertations

Ultra High Performance Concrete (UHPC) and High Performance concrete (HPC) is characterized by high compressive strength and high toughness. This is achieved through maximizing the particle packing density in the matrix and the use of fibers to reinforce the matrix, increasing the materials toughness. The interactions of fibers and the matrix during loading is quite complex and involves several different energy dissipation mechanisms. The goal of this work and this thesis is to investigate these interactions and identify any changes in material response, and hope that these changes may be useful for the design of UHPC moving forward.

In this …

Examining The Impact Of Centerline Rumble-Strip Installation In Prevention Of Head-On And Opposite Sideswipe Collisions In Maine, Jhan Kevin Gil Marin

Electronic Theses and Dissertations

Among all traffic collisions, lane departure crashes are the leading type of serious traffic crashes in Maine, comprising 72% of state-wide traffic fatalities. To reduce these crashes, Maine Department of Transportation (MaineDOT) installed shoulder and centerline rumble strips on roadways to prevent lane departure crashes in Maine. With a total installed length of 1503 miles of rumble strips, specifically 511 miles of centerline rumble strips in bidirectional and undivided rural two-lane roadways, there is a need to understand the impact of rumble strips in reducing lane departure crashes. In this thesis, observational before-after studies with two methods: comparison group, and …

Cement Stabilization Of Poorly Graded Sand, Lana Grayson Brown Sisung

Theses and Dissertations

Stabilization of poorly graded sand in full-scale applications is challenging. This thesis evaluated cement-stabilized sand and had two objectives: (1) evaluation of stabilized material using the PM device to quantify engineering properties for future comparison to alterative materials and to investigate the effectiveness of the device with sand and (2) investigation of the merits of alternative application of cement to sand to benchmark against other topically applied materials. The PM device was successfully used to recommend 10% cement for field studies with one sand, successfully allowed data collection in laboratory and field applications, and its potential in sand seems promising …

Optimization Of Hydraulic Cylinder Positioning For Wind Tower Hydraulic Erection System, Anbesh Rawal

Master's Theses

Wind produced electricity is a rapidly growing field with wind towers serving as critical components. Conventionally, special cranes are commonly used for wind tower erection. This study explores the use of hydraulic cylinders for small-scale wind tower erection. The thesis aims to find the optimal position of hydraulic cylinder connections in a hydraulic erection system for safe and energy-efficient tower erection and retraction and to enhance the performance and longevity of the system.

Structural analysis was conducted to investigate various hydraulic cylinder positioning configurations, ensuring minimal force exertion while maintaining structural integrity. The study included the selection of locally available …

Enhanced Bioretention Modeling At The Catchment-Scale: An Integrated Drainmod-Urban And Swmm Approach, Ghada Diab

Doctoral Dissertations

Bioretention systems are increasingly being adopted in stormwater management as an effective measure to promote infiltration and restore more natural hydrology in urbanized watersheds. Given the significant financial investment in these practices, reliable bioretention models are necessary to predict the effectiveness of these practices prior to installation. One such model, DRAINMOD-Urban (DM-Urban), was recently developed to produce hydrographs with a high temporal resolution at the site-scale, showing substantial promise during initial testing. However, the dataset used for initial testing was limited, consisting of one bioretention area with minimal occasions of overflow. Additionally, DM-Urban is an input-heavy model and there is …

3d Experimental Studies Of Temperature And Crystallographic Effects On Creep And Strength In Rock Salt, Amirsalar Moslehy

Doctoral Dissertations

Salt domes utilization as storage reservoirs in the energy sector has led to extensive studies on rock salt’s mechanical and geothermal behavior. These important facilities’ safety and serviceability rely on understanding rock salt’s compressive strength and creep behavior under various loading directions, water contents, in-situ stresses, and temperatures. Despite numerous studies on rock salt’s mechanical behavior in the literature, there are still many unanswered questions about rock salt’s behavior. This dissertation was aimed at utilizing state-of-the-art experimental techniques such as 3D synchrotron micro-computed tomography (SMT) and 3D x-ray diffraction (3DXRD) along with hundreds of compression and creep experiments to enhance …

Effect Of Seawater And Temperature Upon Carbon Fiber/Vinyl Ester (Cfve) Composites And Its Constituents, Vivek Chawla

Doctoral Dissertations

An experimental and computational investigation has been carried out to: (1) develop micromechanical characterization techniques for polymeric composites and (2) evaluate the effects of seawater and temperature upon the micro- and macro-response of the carbon fiber vinyl ester composites (CF/VE). Compression properties degradation due to short-term and long-term exposure to seawater is evaluated. A 12-16 % reduction in compression strength is observed due to long-term exposure to seawater, which is attributed to a decrease in interfacial shear strength (IFSS) due to long-term exposure to seawater. The developed Push-out methodology is used to characterize the IFSS. The presented approach consistently yields …

Functional Cementitious Composites With Micro-Sized Particulate Fillers For Additive Construction And Energy-Efficient Buildings, Adam Brooks

Doctoral Dissertations

With a growing energy demand, the development of sustainable and energy efficient building materials is growing rapidly. Numerous researches have focused on low carbon footprint construction materials, high-performance thermal insulations, high-performance façade, and thermal energy storage. Among these, the development of functional cementitious composites has attracted significant attention due to its potential utilities in building energy reduction and decarbonatization efforts. For example, fly ash cenospheres have been used as micro-size lightweight fillers to achieve low density and thermal conductivity. The use of phase change materials (PCM) in concrete has been studied to answer energy demands. While their inclusion into concrete …

Decoding Usage And Adoption Behavior Of The Low-Carbon Transportation Market: An Ai-Driven Exploration, Vuban Chowdhury

Graduate Theses and Dissertations

The transportation sector stands as a significant contributor to greenhouse gas emissions in the United States, with its environmental impact steadily escalating over the past few decades. This has prompted government agencies to facilitate the adoption and usage of low-carbon transportation (LCT) options as alternatives to fossil-fuel-powered transportation. LCTs include modes of transportation that minimize the overall carbon footprint of the transportation sector by relying on energy sources that are environmentally sustainable. These sustainable transportation options have also garnered significant interest in the transportation research community. For government agencies and researchers alike, a comprehensive understanding of the adoption and usage …

Determining The Effect Of The Presence Of Food Deserts On The Number Of Crashes In Census Tracts In Arkansas, Lizbeth Juarez-Bartolo

Graduate Theses and Dissertations

Food deserts, areas with limited access to grocery stores which sell fresh produce, dairy, and meats, are a growing concern in many communities. The presence of a food desert is known to cause great impacts on the physical health of the people residing within them, but there is little to no research on a food desert’s influence on the traffic safety of the location in which it encompasses. Based on previous studies into food deserts, studies suggest that food inaccessibility is mostly felt by rural residents. Since rural residents must travel farther distances on more hazardous rural roadways to access …

Self-Consolidating Concrete Design For Drilled Shaft Structural Applications, Grady S. Caton

Graduate Theses and Dissertations

Self-consolidating concrete (SCC) is a relatively new concrete technology which allows the concrete to be placed without the need for manual or machine vibration. This innovation reduces labor costs, construction times, and can provide a smooth, finished surface. However, this technology is used in the United States primarily in the precast and prestressed concrete industry. The utility of SCC in structural applications, such as areas of dense reinforcement or locations where complex geometry makes consolidation impossible, is also advantageous. In this study, a series of SCC mixtures were developed both with and without fly ash replacement. These mixtures were then …

Comparing In-Situ Liquefaction Triggering Procedures For Sites In Arkansas, Sagar Barua

Graduate Theses and Dissertations

There currently exists a significant amount of uncertainty when designing piles for bridge foundations in liquefiable soil. Currently ARDOT engineers use a Standard Penetration Test (SPT) based liquefaction spreadsheet developed 10 years ago to evaluate liquefaction triggering. Since this spreadsheet was developed, updates to the liquefaction triggering procedures have been published making the spreadsheet out-of-date. Moreover, additional methods of liquefaction evaluation using cone penetration test (CPT) and shear wave velocity (Vs) provide added means of evaluating liquefaction potential. This thesis updates ARDOT's liquefaction triggering evaluation methodology with the newest procedures and incorporates additional empirical liquefaction hazard estimates such as the …

Gravel Conveyance System: An Evaluation On E. Coli Removal Capabilities, Madison Grace

<strong> Theses and Dissertations </strong>

In many rural, low-income communities such as the Black Belt of Alabama, there is a lack of wastewater infrastructure and solutions leaving homeowners non-compliant to state and federal law and with potential health risks on their property. New regulations have allowed for onsite, surface discharge for single family homes that are not connected to a centralized sewer or large flow development. These new regulations also contain strict disinfection criteria for the treated wastewater that will be discharged. A low-cost and low-maintenance treatment system that provides adequate disinfection is necessary to allow homeowners to take advantage of the new opportunity for …

Analysis Of Travel Behavior At International Border Crossings: Application Of Travel Surveys, Jennifer Areli Moreno Escamilla

Open Access Theses & Dissertations

Transportation planning provides an insight into the demand and traffic distribution of existingconditions of a region and helps identify future transportation needs. The results generated from forecasting models influence many decisions on the selection of transportation projects and funding allocations. Thus, forecasting models require up-to-date trip information to represent trip patterns and generate representative traffic demand analysis in a such complex areas as binational regions. The purpose of this study is to provide an analysis on travel survey methodology applied to collect trip information at international border crossings. Based on the results of the survey, an analysis on trip pattern …

Transportation Needs Of Older Adults In Suburban And Rural Areas, Dahai Han

Theses and Dissertations

The fact that the average age of the world's population is increasing, which is more pronounced in developed countries, necessitates the understanding of the challenges faced by older adults in accessing transportation services. With advancing age, individuals may experience age-related changes that can notably affect their driving capabilities, emphasizing the importance of alternative transportation alternatives. This challenge is more evident in suburban and rural settings, where transportation choices are limited, and older adults often find themselves without access to suitable transportation alternatives. Given that mobility plays an essential role in maintaining social connections, accessing healthcare services, and fulfilling daily needs, …

Sustainable Cities: Life-Cycle Cost Analysis Of Integrating Piezoelectric Harvesters Into Roadways, Heba Mohamed Gaber

Theses and Dissertations

Energy is essential in our modern era. Because of the increasing electricity consumption, sustainable and Renewable energy became a necessary global approach to fill the gap of the ongoing energy shortage in addition to the climate change crisis due to using conventional ways for energy production. Renewable energy is a global approach that has achieved great accomplishments during the last decades and is gradually increasing. Energy harvesting is considered one of the main resources for renewable energy. Energy harvesting from the roadways is an ingenious horizon for sustainable, clean, and renewable energy generation. Harvesting energy from the roadways by using …

Evaluating The Impact Of Oyster Reef Breakwaters On Hydrodynamics, Morphodynamics, And Sediment Transport Using Xbeach, Tabassum Islam

<strong> Theses and Dissertations </strong>

Alabama Port is a unique marsh and sandy beach shoreline. Since the 1950s, substantial erosion has occurred along this shoreline due to storms, wind-generated waves, and ship wakes. This research focuses on evaluating the effect of oyster reef breakwaters on wave height attenuation and sediment stabilization through numerical modeling (XBeach) under three different synthetic storm scenarios coupled with three unique sea level rise projections near Alabama Port. This has been accomplished by comparing a with and without project condition using XBeach in a two-dimensional (2D) mode by analyzing wave height, velocity, and cumulative bed-level changes at the study site. The …

Component Approach For A Combined Hurricane Wind And Rainwater Damage And Time Related Expenses Model In Mid/High-Rise Buildings, Zhuoxuan Wei

Theses and Dissertations

This dissertation focuses on mid/high-rise commercial residential buildings (MHRB) vulnerable to wind-driven rainwater ingress during hurricanes. The author developed the WHIP-MHRB model, a new probabilistic vulnerability model funded by the Wind Hazard Infrastructure Performance Center (WHIP-C). This model combines the estimates of rainwater ingress, distribution and propagation, and damage assessments, and time-related expenses (TRE) predictions for MHRB during hurricanes. Embedded within WHIP-MHRB is the WHIP-TRE model, which forecasts repair times, delay times, downtime, and recovery times post-hurricane explicitly.

Furthermore, taking advantage of the new model, this study presents two approaches to address the combined wind and rain vulnerabilities of MHRB …

Development Of Scope Of Services For Procurement Of Professional Consultant Services On Transportation Projects – A Study Of South Carolina Department Of Transportation, Ajay Jadhav

All Dissertations

Project Scoping Process (PSP) is one of the significant steps that starts at the very beginning of the project life cycle. During project initiation phase, project scoping is kicked off which includes documenting a list of project-specific goals, deliverables, tasks, costs, and deadlines. The scoping phase duration depends on the project complexity and involves various stakeholders, establishing team, confirming the project purpose and need, initiating the environmental revie process, determining the level of environmental documentation and permit requirements, conducting survey, identifying project risks and tools to mitigate them, and evaluating public involvement strategies. A well-defined PSP is therefore essential for …

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …

Effect Of Latex Modified Concrete Overlays With Reduced Surface Preparation On The Load Distribution And Flexural Strength Of Channel Girders, Samuel Dodd

All Theses

This thesis investigates the use of a Latex Modified Concrete (LMC) overlay to increase the strength of prestressed channel girders and enhance their ability to distribute load. The research conducted in this thesis involved material testing of several different LMC mixes and flexural testing of an LMC overlay and girder system. The material testing was used to determine a reasonable LMC mix design and surface preparation method to be used for the overlay. Based on material testing it was concluded that a rapid-set mix and pressure washing of the girder surfaces were a reasonable mix design and surface preparation for …

Modular Composite Sandwich Structures For Thermal And Structural Retrofitting Of Existing Buildings, Marc Al Ghazal

Masters Theses

Around 40% of global energy consumption and 30% of worldwide carbon dioxide (CO2) emissions are attributed to buildings. Most of this consumption is dedicated to ensuring thermal comfort. The goal of this research was to develop and field validate retrofit solutions to improve the energy efficiency of buildings. Exterior cladding panels were designed and tested to ensure adequate thermal and structural performance. Sandwich panels (glass fibers reinforced polymer (GFRP) skins and polymeric foam cores) were fabricated using the vacuum assisted resin transfer molding (VARTM) process. Extruded polystyrene (XPS) and polyurethane (PU) foams were compared as core materials through a series …

Probability Distribution Fitting For Censored Data: A Practical Guide For Survival Analysis Of Nbi Data For Concrete Bridge Decks In Oregon, Asmaa Almeshaileh

Dissertations and Theses

Many sophisticated statistical models and analyses have been proposed to analyze datasets derived from the national bridge inventory (NBI). These objectives range from creating an understanding of the factors that drive the deterioration of bridge members to providing agencies with quantitative information for their maintenance and repair decisions. As these models become increasingly sophisticated and difficult to comprehend and implement, practicing engineers and owners are less likely to use them. Often, however, grouping data intuitively, for example, per a select structure type or condition rating and analyzing them using prescriptive statistics such as distribution fitting, does not only lie in …

Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani

LSU Master's Theses

Uncontrolled groundwater exploitation can lead to aquifer depletion, land subsidence, and saltwater intrusion. Effective groundwater management is challenging due to the intricate nature of subsurface hydrogeology and spatiotemporally variable pumping, especially in a multi-aquifer system. To ensure sustainable withdrawal, multi-objective optimization is an effective tool for balancing management goals and drawdown effects. However, running simulation-optimization using detailed groundwater models is computationally expensive, pushing decision-makers to decide based on limited scenarios. In this study, a hydrogeological framework was constructed for the Capital Area, Louisiana, allowing for individual assessment of each unit to better understand each aquifer's condition. Moreover, a surrogate-assisted simulation-optimization …

A Bayesian Network-Based Methodology For Improved Bridge Load Rating And Asset Management, Jeffery Mark Roberts

Dissertations and Theses

From the day a new structure is made available for use, to the day that the structure is no longer able to fulfill an intended purpose, structural safety is a vital interest. Managing a portfolio of structures can be a difficult undertaking for an asset manager, particularly if different types of structures are being maintained. The goal is to manage assets in the most efficient manner which can be influenced by, at a minimum, safety and financial concerns.

A potential tool for an asset manager or owner is the use of Bayesian Networks (BNs). When a BN is used to …

Interdependency Between Water And Road Infrastructures: Cases And Impacts, Shihab Uddin

USF Tampa Graduate Theses and Dissertations

This dissertation studies the interdependency between road and water infrastructures and associated interdependency impact on these two critical infrastructure systems. Critical infrastructures and the interdependency among these infrastructures have gained much attention recently because of its growing complexity, importance, and vulnerability to natural and man-made threats. In response, researchers have spent significant effort to study these infrastructures individually as well as when they are interdependent to understand complex interdependency relationship and to figure out ways to make these infrastructures more reliable, robust, and resilient. However, water and road infrastructure systems have not been studied as vastly as other critical infrastructures …

Integrating The Concept Of Complete Streets Into Pavement Preservation, Sirisha Gangireddy

LSU Master's Theses

This study is motivated by the evident gap in integrating Complete Streets principles into pavement preservation. Complete Streets opportunities, which aim to accommodate all road users, are typically encouraged in all kinds of projects including new construction, reconstruction, preservation, and rehabilitation. While the concept of Complete Streets is understood in terms of new construction (e.g., building sidewalks), its application through pavement preservation programs is not well-developed. To bridge the gap between the Complete Streets and pavement preservation, this study conducted a comprehensive review on how state Department of Transportation (DOTs) are currently incorporating Complete Streets into pavement preservation and identified …