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Civil Engineering

Theses/Dissertations

2024

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Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru May 2024

Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru

Master's Theses

The development of each nation is dependent on its infrastructure, and nations are competing with others in infrastructure, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are cement and asphalt, which pose significant environmental challenges. This thesis explores the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. The study examines the impact of FA and CS percentages and the particle sizes of CS on the compressive strength, …


Effect Of Waste Covid-19 Masks On Compaction Characteristics Of Silty-Clay Soil, Sydney K. Lawson May 2024

Effect Of Waste Covid-19 Masks On Compaction Characteristics Of Silty-Clay Soil, Sydney K. Lawson

Honors College Theses

The present study aims to explore the effect of adding shredded waste Covid-19 masks to silty-clay soil on the soil’s compaction characteristics for beneficial use in embankment, the subgrade of roadways, or backfill. This was accomplished by using two different types of masks: blue surgical masks and KN95 masks. Both mask types were hand shredded into half-inch sections using safety-scissors. The maximum dry density (MDD) and optimum moisture content (OMC) are the two most important compaction characteristics, and they were determined by the Standard Proctor Compaction Test (ASTM D698 / AASHTO T99). The change of both the MDD and OMC …


Selecting Industry 4.0 Technologies For Construction Activities Using Clustering Analysis And Text Mining, Benyamin Sadeghi May 2024

Selecting Industry 4.0 Technologies For Construction Activities Using Clustering Analysis And Text Mining, Benyamin Sadeghi

Theses and Dissertations

Construction 4.0, which involves the application of Industry 4.0 technologies in construction activities, promises to revolutionize the construction industry by improving productivity, enhancing safety, promoting sustainability, and strengthening quality in the age of the Information Revolution. Industry 4.0 technologies such as Artificial Intelligence (AI), robotics, and the Internet of Things (IoT), have the potential to radically transform the construction industry in the 21st century. Construction activities constitute approximately 4.3% of the US gross domestic product-GDP and account for creating 7.5 million jobs. Although productivity has significantly increased in other industries, progress has been slow in the construction sector. One contributing …


Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley May 2024

Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley

Civil Engineering ETDs

Meteorological, hydrological, and biogeochemical processes naturally control stream ecosystems. These processes define the frequency and distribution of precipitation and the supply and demand of solutes and particles to support aquatic food chains through space and time. Studies have also found that stream ecosystems are also controlled by anthropogenic activities, which occur on a much shorter timescale. These anthropogenic activities affect stream ecosystems' structure and function from local to planetary changes to the environment. It is essential for scientists and engineers to understand the relationships between naturally occurring processes and those created by human activities for a better interpretation of stream …


An Audio-Based Emotion Monitoring System For Enhancing Construction Worker Safety, Mengjun Wang May 2024

An Audio-Based Emotion Monitoring System For Enhancing Construction Worker Safety, Mengjun Wang

Masters Theses

The high suicide rate among construction workers in the U.S. is a concerning issue. For every 100,000 workers in this field, 53.3 are reported to commit suicide, compared to the national average of 12.93. This statistic highlights the importance of addressing the mental well-being of construction workers, which directly impacts their performance and safety on the job. In this research, an audio-based system is proposed to monitor the emotions of construction workers in real-time, aiming to enhance their safety and address potential concerns proactively. The system involves a novel stimulus mechanism that encourages workers to interact with an AI, which …


Investigation Into The Effect Of Mixture Composition On Setting Time Of Magnesium Phosphate Cement, Autumn Broglen May 2024

Investigation Into The Effect Of Mixture Composition On Setting Time Of Magnesium Phosphate Cement, Autumn Broglen

Civil Engineering Undergraduate Honors Theses

Magnesium phosphate cement (MPC) is a cementitious material that is formed through an acid-base reaction between magnesia and phosphate. This reaction occurs rapidly, making MPC an appealing choice for rapid repair applications. The purpose of this project is to investigate the impact of different proportions of class F fly ash, set retarder consisting of a mixture of boric acid and dextrose, magnesium to phosphate ratio, and water/cement ratio on the initial setting time of MPC paste. Different mixtures of MPC paste were developed to vary the proportions of each constituent, and setting time of each mixture was determined using the …


Effect Of Swirl Ratio On Simulated Vortech Chamber Vortex Parameters, Samuel Kolar May 2024

Effect Of Swirl Ratio On Simulated Vortech Chamber Vortex Parameters, Samuel Kolar

Civil Engineering Undergraduate Honors Theses

A numerical simulator can use computational fluid dynamics (CFD) to model an experimental tornado-simulating chamber at Texas Tech University (known as VorTECH). Previous studies evaluating this particular CFD model have produced results that compare the touchdown swirl ratio (STD), core radius (rc), maximum tangential velocity at touchdown (Vtmax @ STD), and height of the maximum tangential velocity (zc) reasonably well with experimental data from the VorTECH facility. The effects of swirl ratio beyond STD on important vortex parameters including rc, Vtmax, z …


Development And Evaluation Of An Arsenic Transport Model For The Maurice River Watershed, Christina Eddleman May 2024

Development And Evaluation Of An Arsenic Transport Model For The Maurice River Watershed, Christina Eddleman

All Theses

For many Superfund sites across the United States, arsenic is one of the most common contaminants of concern that must be cleaned up to protect human and environmental health. Past research and health studies have documented the harmful effects of inorganic arsenic on humans and the environment but selecting an appropriate remediation plan depends on several site-specific factors at each Superfund site. To assist in determining an appropriate remediation plan, sediment and contaminant transport models have been used to simulate the transport of arsenic and other contaminants of concern at contaminated sites to, e.g., make relative comparisons of the efficacy …


Engineering Sustainable Bridge Deck Rehabilitation: Evaluating Mechanical And Electro-Chemical Properties Of Rapid-Set Patching Materials And Their Influence On Repair Durability, James Roberts May 2024

Engineering Sustainable Bridge Deck Rehabilitation: Evaluating Mechanical And Electro-Chemical Properties Of Rapid-Set Patching Materials And Their Influence On Repair Durability, James Roberts

All Theses

As the state of the US infrastructure continues to deteriorate over time, a prominent issue especially in the field of reinforced concrete structures has been the ability to properly rehabilitate and extend the design service life of these structures. A majority of our existing reinforced concrete bridges were built in the construction boom during the 60’s, 70’s and 80’s, and were originally designed with a service life of approximately 50 years, thus showing that many structures are close to or have already exceeded their intended service life. Additionally, with a poor history of government infrastructure funding, it is seen to …


Quantifying Hurricane Effects On Housing: Evaluating Damage, Loss, And Shelter Demands Using Historical And Simulated Storm Tracks, Adish Deep Shakya May 2024

Quantifying Hurricane Effects On Housing: Evaluating Damage, Loss, And Shelter Demands Using Historical And Simulated Storm Tracks, Adish Deep Shakya

All Theses

This research introduces an advanced framework which employs parametric wind field models for peak wind speeds, and building fragility curves, loss functions, and demographic data to estimate for estimating housing damage and loss. The uninhabitable units immediate displaced households, short-term and long-term shelter need households are determined. with a particular focus on those eligible for FEMA assistance. The framework's validity is reinforced by a high correlation in the analysis of recent hurricane events between estimated numbers of displaced households and actual FEMA aid recipients, where FEMA aids about 20-60% of the predicted long-term displaced households. A novel application of the …


Using Genetic Algorithm And Geographic Information System For Equity-Driven Transportation Planning And Analysis, Emiliano Del Rio Reyes May 2024

Using Genetic Algorithm And Geographic Information System For Equity-Driven Transportation Planning And Analysis, Emiliano Del Rio Reyes

Open Access Theses & Dissertations

Efforts to address equitable access in public transit planning have gained momentum, spurred by incentives for Metropolitan Planning Organizations (MPOs) and State Departments of Transportation (DOTs). However, traditional strategies often fall short of meeting the needs of disadvantaged communities, particularly in underserved areas. This study presents a pioneering methodology leveraging Genetic Algorithms (GA) and Geographic Information Systems (GIS) to optimize bus stop placement, aiming to enhance equitable access in public transit systems. Focusing on Route 16 of Sun Metro in El Paso, Texasâ??a critical feeder route linking the Westside Transit Center to Upper Valley neighborhoodsâ??the research commences with a comprehensive …


Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil May 2024

Routing Opportunities For Commercial Crossings Between El Paso And Juarez, Marek Musil

Open Access Theses & Dissertations

This thesis explores the topic of commercial movements between the El Paso and Ciudad Juarez road networks and the implications of the possible changes in their routing. This area houses several ports of entry, which present one of the busiest commercial and personal border crossings in the whole nation. The primary focus was to evaluate the recently proposed reconstruction scenario of removing trucks from the Bridge of the Americas and study the impacts on the flows throughout the other ports. The chosen tool to support the analysis is a mesoscopic simulation software called DynusT, which is capable of modeling the …


Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek May 2024

Smart Public Transportation And Mobility Hub Design In El Paso, Jiri Vojtisek

Open Access Theses & Dissertations

This thesis explores the potential of a Smart Public Transportation concept and mobility hub design as tools to mitigate the growing trend of transportation issues, such as traffic congestion, reliance on privately owned vehicles, or unattractive public transportation. Consequently, residentsâ?? lives are negatively affected by excessive noise, air pollution, and travel delays, leading to increased safety risks, lost productivity, and a lower quality of life. Considering these challenges, the study begins by analyzing the current state of public transportation in El Paso. Next, it introduces a toolkit from the Smart City concept, followed by case studies of best practices of …


Analytical And Experimental Studies To Support Codification Of Lightweight Grout For Masonry Design, Cooper Banks May 2024

Analytical And Experimental Studies To Support Codification Of Lightweight Grout For Masonry Design, Cooper Banks

All Theses

Lightweight (LW) aggregates have many potential benefits in masonry construction including minimizing mass, improving thermal performance, and reducing the potential for shrinkage cracking via internal curing. The current masonry design standard, TMS 402/602-22, permits lightweight aggregate in the production of concrete masonry units (CMU), but there has been insufficient testing of masonry assemblies to permit designing with LW grout. Shrestha et al. characterized LW grouts bond to reinforcement, shear strength, tension and shear pullout behavior of anchors and proposed possible reduction factors for design. Hiner characterized the flexural bond strength LW grouted masonry assemblies and proposed possible reduction factors for …


Assessment Of Engineering Performance And Environmental Impacts Of High Reclaimed Asphalt Pavement (Rap) Asphalt Mixtures In Flexible Pavements, Ibrahim A.I.E. Elnaml Apr 2024

Assessment Of Engineering Performance And Environmental Impacts Of High Reclaimed Asphalt Pavement (Rap) Asphalt Mixtures In Flexible Pavements, Ibrahim A.I.E. Elnaml

LSU Doctoral Dissertations

Due to the critical role of asphalt pavements in national infrastructure development, there is a pressing need to investigate more sustainable materials and approaches. The use of natural aggregates and asphalt binders in asphalt pavement presents sustainability challenges due to the depletion of finite resources. Recycling Asphalt Pavement (RAP) offers a promising sustainable solution by substituting virgin aggregates and asphalt binders with recycled ones. However, increasing RAP contents in asphalt mixtures (>25%) can lead to premature cracking, insufficient durability, and limited longevity due to the presence of aged RAP-asphalt binder. To address these concerns, the application of novel recycling …


Stability And Strength Of Glass Frp Beam-Columns With Biaxial Bending And Torsion Including Shear And Warping Deformations, Emad M. Amin Apr 2024

Stability And Strength Of Glass Frp Beam-Columns With Biaxial Bending And Torsion Including Shear And Warping Deformations, Emad M. Amin

Civil & Environmental Engineering Theses & Dissertations

Presented herein is a study of the stability and strength of pultruded glass fiber reinforced polymer (Glass FRP) beam-columns with an I-shaped cross section subjected to biaxial bending and torsion including shear and warping deformations. Three coupled differential equations of equilibrium including second-order effects and geometric imperfections are formulated and solved using a finite-difference scheme. Laboratory experiments are also conducted on glass FRP members with applied torsion; axial load; combined axial load with biaxial bending; and combined axial load, biaxial bending and torsional moment, respectively, for comparison to the theoretical predictions. The theoretical results agreed well with the experiments for …


Dynamic Soil-Structure Response And Failure Of Wood Utility Poles Under Hurricane-Force Wind And Non-Linear Cable Loads, Ramani Ayakannu Apr 2024

Dynamic Soil-Structure Response And Failure Of Wood Utility Poles Under Hurricane-Force Wind And Non-Linear Cable Loads, Ramani Ayakannu

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents the outcome of a study of the dynamic soil-structure interaction response of tapered wood utility poles embedded in various foundation soils subject to quasi-static and dynamic wind loads. The study includes the effects of nonlinear soil behavior with varying quantities of moisture and nonlinear cable tension loads on a class H1 wood pole. The natural frequency response of the pole is determined using a finite element formulation. The dynamic response in the presence of wind-induced forcing function is studied using a SAP2000 finite element scheme with wind speeds up to 220 mph. The natural frequency of the …


Quasi-Static And Impact Load Response Of Bfrp-Reinforced Concrete Beams And Post-Terrorist-Attack Sub-Assemblages, José Luis Carrasquillo Apr 2024

Quasi-Static And Impact Load Response Of Bfrp-Reinforced Concrete Beams And Post-Terrorist-Attack Sub-Assemblages, José Luis Carrasquillo

Civil & Environmental Engineering Theses & Dissertations

This dissertation presents the outcome of a theoretical and experimental study of Basalt Fiber Reinforced Polymer (BFRP) reinforced concrete beams and post-terrorist-attack subassemblages subjected to either quasi-static or impact load. Both BFRP reinforcement as well as BFRP fabric are used in this investigation. The sub-assemblage consists of an otherwise two-span beam converted to a fixed-end single-span one owing to the loss of a middle column blasted off during the terrorist attack. The simply supported beams are subjected to a midspan quasistatic or an impact load. However, each sub-assemblage is subjected to a quasi-static load up to collapse to simulate the …


Combine Effects Of Heavy Storm, Sea Level Rise, And Wind-Induced Surge On Flooding In A Low-Gradient Coastal Watershed In Eastern Virginia, Rutvik Rajendrabhai Patel Apr 2024

Combine Effects Of Heavy Storm, Sea Level Rise, And Wind-Induced Surge On Flooding In A Low-Gradient Coastal Watershed In Eastern Virginia, Rutvik Rajendrabhai Patel

Civil & Environmental Engineering Theses & Dissertations

This dissertation examines and presents mechanisms of flooding in a low-gradient coastal watershed, located in Virginia Beach, Virginia, USA. The watershed comprises the North Landing River watershed and the West Neck Creek watershed, both characterized by a low topographic gradient. The analysis relied on examining simulations generated using one-dimensional and two-dimensional HEC-RAS models. These models were developed using a 1-m digital elevation model (DEM) obtained from the U.S. Geological Survey (USGS). To calibrate and validate the models, unsteady flows resulting from historical hurricanes (e.g., Matthew, Sandy, and Isabel), southern winds, and/or rising sea levels were utilized. Some flows were caused …


Thermo-Elasto-Plastic Stability Of Biaxially Loaded Hollow Rectangular Section Steel Beam-Columns With Applied Torsion, George Adomako Kumi Apr 2024

Thermo-Elasto-Plastic Stability Of Biaxially Loaded Hollow Rectangular Section Steel Beam-Columns With Applied Torsion, George Adomako Kumi

Civil & Environmental Engineering Theses & Dissertations

Presented herein is an experimental and theoretical study of biaxially loaded hollow rectangular section steel beam-columns with applied torsion at elevated temperatures. The theoretical analysis is based on a system of simultaneous materially nonlinear differential equations of equilibrium for which an iterative semi-analytic solution approach is formulated. Although the primary goal of this research is to study the influence of elevated temperatures on the steel member with the complex loading, rigorous analysis is also conducted of the member at ambient temperature for comparison. The experimental part of the study involves conducting tests on the members at both ambient and high …


Safety Investigation Of Crash Rates During Hurricane Evacuations, Amelia K. Lawson Mar 2024

Safety Investigation Of Crash Rates During Hurricane Evacuations, Amelia K. Lawson

Doctoral Dissertations and Master's Theses

This study aimed to investigate crash rates across four distinct periods—evacuation, re-entry, emergency, and non-emergency—during Hurricanes Matthew (2016), Irma (2017), and Michael (2018). A notable gap in existing research pertains to understanding crash rates during these critical phases of hurricane events. By addressing this gap, this research contributes to a deeper comprehension of evacuation transportation safety. The methodology employed ArcMap to construct an interactive map for data collection, encompassing key variables such as the number of crashes, traffic volumes, duration of each period under analysis, and roadway segment lengths for each hurricane. Evaluating the crash rate per million vehicular miles …


Numerical Study Of Cone Penetration In Calcareous Sands: Investigating Cone Tip Resistance Correction Factors For Crushable Soils, Stephanie Michelle Hyder Mar 2024

Numerical Study Of Cone Penetration In Calcareous Sands: Investigating Cone Tip Resistance Correction Factors For Crushable Soils, Stephanie Michelle Hyder

Dissertations and Theses

The cone penetration test (CPT) is used to characterize the behavior and properties of soils, including the susceptibility to earthquake liquefaction triggering. The cone tip resistance relates to liquefaction susceptibility through relative density, where relative density is closely related to both cone tip resistance and liquefaction susceptibility. Currently, published methods of estimating liquefaction potential (i.e., cyclic resistance ratio) are based on silica sands and do not properly characterize calcareous sands. The measured cone tip resistance in calcareous sands is lower than in silica sands at the same relative density; this difference is generally attributed to the higher compressibility of calcareous …


Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied Feb 2024

Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied

Theses and Dissertations

Accurate cost estimation is pivotal for the success of construction projects, yet the industry grapples with challenges related to cost overruns. Uncertainties and unforeseen variables often introduce discrepancies, particularly during the planning phase. Economic changes, considered uncontrollable risks, significantly influence these fluctuations. Various research endeavors have quantified the impact of economic conditions on construction costs, emphasizing the correlation between economic indicators and project expenses. Addressing these challenges, the Construction Cost Index (CCI), a tool introduced by Engineering News Record (ENR), accurately delineates the correlation between economic changes and construction costs. Despite its global efficacy, an Egyptian Construction Cost Index is …


Containerization Of Seafarers In The International Shipping Industry: Contemporary Seamanship, Maritime Social Infrastructures, And Mobility Politics Of Global Logistics, Liang Wu Feb 2024

Containerization Of Seafarers In The International Shipping Industry: Contemporary Seamanship, Maritime Social Infrastructures, And Mobility Politics Of Global Logistics, Liang Wu

Dissertations, Theses, and Capstone Projects

This dissertation discusses the mobility politics of container shipping and argues that technological development, political-economic order, and social infrastructure co-produce one another. Containerization, the use of standardized containers to carry cargo across modes of transportation that is said to have revolutionized and globalized international trade since the late 1950s, has served to expand and extend the power of international coalitions of states and corporations to control the movements of commodities (shipments) and labor (seafarers). The advent and development of containerization was driven by a sociotechnical imaginary and international social contract of seamless shipping and cargo flows. In practice, this liberal, …


Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali Jan 2024

Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali

Theses and Dissertations

The study aims to evaluate the impact of warm mix additives (WMA) on the rheological and performance properties of asphalt binders and mixtures. For this purpose, PG 76-28 and PG 58-28 were obtained with one organic (Sasobit Redux) and three chemical WMA (Rediset, Evotherm, and Zycotherm). All WMA-modified asphalt binders were aged at three different aging levels. Laboratory tests such as performance grade (PG), critical temperature differential (ΔTc), asphalt binder cracking device (ABCD), linear amplitude sweep test (LAS), and Fourier transform infrared spectroscopy (FTIR) were performed. In addition to the binder testing plan, this study also evaluated the impact of …


Floating Offshore Wind Turbine Analysis And Discovery, Payton Maddaloni Jan 2024

Floating Offshore Wind Turbine Analysis And Discovery, Payton Maddaloni

Honors Theses and Capstones

No abstract provided.


Effect Of Admixtures On Rapid Hardening, Self-Consolidating Concrete, Haley Johnson Jan 2024

Effect Of Admixtures On Rapid Hardening, Self-Consolidating Concrete, Haley Johnson

Theses and Dissertations--Civil Engineering

Self-consolidating, rapid-hardening concrete is a sought-after product in the market now, however the effects of admixtures on fresh and hardened concrete rheology are still uncertain. This study aims to create a self-consolidating concrete (SCC) using calcium sulfoaluminate (CSA) cement for its rapid-hardening properties, and tests two set time retarders and two viscosity-modifying admixtures (VMAs) to determine how they affect the properties of concrete. The properties studied in this thesis are workability, viscosity, set times, air content, compressive strength, and freeze-thaw resistance of self-consolidating concrete. It was found that tartaric acid creates a very workable SCC with consistent results regardless of …


Impact Of Augmented Documentation Workflows On Transportation Agency Asphalt Paving Operations: A Qualitative And Quantitative Study, Josh Withrow Jan 2024

Impact Of Augmented Documentation Workflows On Transportation Agency Asphalt Paving Operations: A Qualitative And Quantitative Study, Josh Withrow

Theses and Dissertations--Civil Engineering

e-Ticketing was an intriguing technology to many state transportation agencies (STAs) pre-COVID-19 pandemic but gained significant attention upon arrival of the pandemic due to the contactless nature of the technology. Research completed prior to the pandemic into e-ticketing for asphalt paving primarily identified qualitative benefits and concerns. However, minimal academic literature exists in the post-pandemic era discussing the additional e-ticketing benefits not previously captured which resulted in increased implementation by STAs. This research seeks to address this gap by gathering information from state members of the American Association of State Highway and Transportation Officials Committee on Construction (AASHTO COC), employees …


Estimation Of Mechanical Behavior Of Unsaturated Soils From A Soil-Water Characteristic Curve, Lucas Acheampong Jan 2024

Estimation Of Mechanical Behavior Of Unsaturated Soils From A Soil-Water Characteristic Curve, Lucas Acheampong

Theses and Dissertations--Civil Engineering

The small-strain shear modulus and shear strength are two crucial mechanical behaviors used in the design of geotechnical structures and in the analyses of earth materials subjected to static and dynamic loadings. Traditional testing methods for these parameters are expensive and time-consuming. This research aimed to address these challenges by developing a model based on the inverse relationship between mechanical behavior of unsaturated soils and the soil-water characteristic curve (SWCC). The proposed model integrates a scaling function to align the SWCC with the mechanical property curve. Empirical relationships were established for the scaling function, specifically aligning with the air-entry value …


Geophysical Method Used For The Determination And Prediction Of Soil Strength And Stiffness Parameters, Dabo Adama Jan 2024

Geophysical Method Used For The Determination And Prediction Of Soil Strength And Stiffness Parameters, Dabo Adama

Theses and Dissertations--Civil Engineering

This paper presents the results of an effort to use geophysical measurements such as seismic wave velocities and electrical resistivities to calculate airfield design parameters. The study converts all geophysical measurements to equivalent California Bearing Ratio (CBR) values, comparing CBR values estimated from DCP penetration resistance with CBR values estimated from shear wave velocity and electrical resistivity values. Relationships linking the geophysical measurements to CBR estimates were established using laboratory data and applied to field in-situ measurements. The elastic modulus (E) is the stiffness parameter involved in predicting soil strength and stiffness. This research aims to relate electrical conductivity and …