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Full-Text Articles in Structural Engineering

Software Literacy In Construction, Aidan Cazares Jan 2025

Software Literacy In Construction, Aidan Cazares

Williams Honors College, Honors Research Projects

The construction industry increasingly relies on software like Bluebeam Revu for their quantity takeoff, document management, and collaboration needs. This project will outline pertinent information obtained through their Bluebeam professional training program and reflect it with a detailed estimate of a real life construct project.


Structural Analysis And Design Methodologies Of Roller Coasters, Benjamin Komar Jan 2025

Structural Analysis And Design Methodologies Of Roller Coasters, Benjamin Komar

Williams Honors College, Honors Research Projects

This project explores the structural analysis behind the design of roller coaster tracks and supports as practiced by modern engineers. It also examines various roller coaster design methods currently in use. This research will be used to craft a detailed explanation of the roller coaster design process. Additionally, a 3D model of a roller coaster was developed based on the researched design procedures, featuring three track sections with different loading conditions to create a supporting structure for 2D truss analysis. The results of the truss analysis were then compared to those obtained using RISA-3D, a finite element structural design software.


Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat Jan 2025

Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage …


Class-Wise Histogram Matching-Based Domain Adaptation In Deep Learning-Based Bridge Element Segmentation, Tarutal Ghosh Mondal, Zhenhua Shi, Haibin Zhang, Genda Chen Jan 2025

Class-Wise Histogram Matching-Based Domain Adaptation In Deep Learning-Based Bridge Element Segmentation, Tarutal Ghosh Mondal, Zhenhua Shi, Haibin Zhang, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study focused on the problem of domain shift in deep learning-based bridge element segmentation. The impracticability of accounting for all possible variabilities vis-à-vis structural shape, size, color, texture, illumination, and other operational conditions in the training process leads to the deterioration in the model performance when applied to test data from novel unseen domains. In such situations, rebuilding the model with labeled training data from the target domain becomes prohibitively expensive and time-consuming in many practical cases. Recent advancements in unsupervised domain adaptation techniques are known to provide viable solutions to this problem. However, it was observed in this …


Influence Of Deck Area And Average Daily Traffic On The Deterioration Of Bridge Superstructures., Faysal Ahamed Jan 2025

Influence Of Deck Area And Average Daily Traffic On The Deterioration Of Bridge Superstructures., Faysal Ahamed

Graduate Theses, Dissertations, and Problem Reports (ETD)

State Departments of Transportation (DOTs) are responsible for maintaining approximately 623,000 bridges across the United States. Effective bridge management requires a comprehensive understanding of the factors influencing structural deterioration. Numerous studies have explored the effects of average daily traffic (ADT) and deck area (DA) on bridge deck deterioration. Given the interdependence between bridge decks and superstructures, it is plausible that ADT and DA significantly influence superstructure condition ratings and deterioration trends. However, their impact on superstructures remains insufficiently studied. In addition, existing studies primarily focus on overall bridge deterioration without adequately differentiating between superstructure designs and materials and maintenance authorities. …


Comparative Analysis Of Lidar And Close-Range Photogrammetry Techniques For Inspection Of Mse Walls In Two Georgia Bridges, Md. Mehrab Hossain Jan 2025

Comparative Analysis Of Lidar And Close-Range Photogrammetry Techniques For Inspection Of Mse Walls In Two Georgia Bridges, Md. Mehrab Hossain

College of Graduate Studies: Theses & Dissertations

Mechanically Stabilized Earth (MSE) retaining walls are durable, settlement tolerant, easy to install, and present cost-effectiveness, in highway bridges. Nevertheless, the cost of repairing MSE walls is high, and it is crucial to have an accurate, quantitative, and scalable inspection method for early detection of potential problems. This study aims to analyze and evaluate undesired displacements that may affect these walls over time. For this, two remote-sensing technologies are considered: Light Detection and Ranging (LiDAR) and 3D Close Range Photogrammetry (CRP). Their performances are compared against an accurate Robotic Total Station (RTS) device, serving as the benchmarking instrument. This work …


Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker Jan 2025

Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker

College of Graduate Studies: Theses & Dissertations

This study seeks to investigate a testing methodology that utilizes accelerated testing methods (ATM) in conjunction with nondestructive testing methods (NDT) to assess destructive ion attacks on concrete. Through the testing of concrete samples, the impacts of chloride and sulfate ions on concrete will be tested by subjecting concrete to cyclic testing in an artificial climate environment. Electrical resistivity (ER) and ultrasonic pulse velocity (UPV) testing will evaluate the impact of the accelerated testing on the migration of destructive ions within the pore structure of the tested concrete. Based on this investigation, comparisons between accelerated, non-accelerated, and control samples will …


Unmanned Vehicle Having Flight Configuration And Surface Traverse Configuration, Genda Chen, Alec Reven, Bo Shang, Zenhua Shi, Liujun Li, Boyang Li Jan 2025

Unmanned Vehicle Having Flight Configuration And Surface Traverse Configuration, Genda Chen, Alec Reven, Bo Shang, Zenhua Shi, Liujun Li, Boyang Li

Patents

An unmanned vehicle includes a body, at least one power source coupled to the body, a flight propulsion system coupled to the at least one power source and configured to propel the unmanned vehicle through air, and a surface propulsion system coupled to the at least one power source and configured to propel the unmanned vehicle along a surface. The unmanned vehicle is configured to switch between a flight configuration in which the unmanned vehicle is propelled through air via the flight propulsion system, and a surface traverse configuration in which the unmanned vehicle is propelled along the surface via …


Reuse Of Calcium Carbonate (Caco3) Recovered From Discarded Carpets As Filler In Fiber-Reinforced Polymer (Frp) Composites, Roshan Devkota Jan 2025

Reuse Of Calcium Carbonate (Caco3) Recovered From Discarded Carpets As Filler In Fiber-Reinforced Polymer (Frp) Composites, Roshan Devkota

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over four billion pounds of carpet are discarded annually in the United States, making carpet waste a significant environmental concern. Calcium carbonate (CaCo₃) constitutes up to 45% of the mass of most synthetic carpets. Reusing this CaCo₃ as a filler in the rapidly growing fiber-reinforced polymer (FRP) industry, which is projected to reach USD 10.38 billion, presents a low-cost, practical approach to developing a market-based solution to post-consumer carpet waste.

This study investigates the reuse of CaCo₃ recovered from discarded carpet backing as a filler in FRP composites, focusing on its mechanical viability in comparison to virgin CaCo₃. The methodology …


Mitigating Frost Heave And Thaw Weakening In Roads Using Wicking Geotextile, Javad Galinmoghadam Jan 2025

Mitigating Frost Heave And Thaw Weakening In Roads Using Wicking Geotextile, Javad Galinmoghadam

Doctoral Dissertations

"Excess water is known to be the primary cause of soil and foundation problems. In cold regions, water-related problems are exacerbated by seasonal freezing and thawing cycles. Frost heave and thaw weakening is the leading cause of premature pavement failure and consume considerable budgets of the Department of Transportations in cold regions. The first step to designing mitigation measures is the ability to predict frost heave under different conditions. This study aims to introduce a new method for quantifying frost heave using a prediction model based on the state surface approach. This proposed model addressed many inconsistencies and limitations of …


Effects Of Peel Angle And Strain Rate On The Bond Between Frcm Composite And Concrete Substrate, Lucas Robert Gervais Jan 2025

Effects Of Peel Angle And Strain Rate On The Bond Between Frcm Composite And Concrete Substrate, Lucas Robert Gervais

Electronic Theses and Dissertations

Fiber-reinforced cementitious matrix (FRCM) composites have gained increasing attention for the rehabilitation and strengthening of concrete and masonry structures due to their favorable mechanical properties, compatibility with existing substrates, and ease of application. The effectiveness of any strengthening procedure depends on the quality of the bond between the external reinforcement and the substrate, ensuring efficient stress transfer and enabling the system to reach its ultimate capacity without premature debonding. While research has focused on the bond performance of FRCM systems under pure shear loading and quasi-static, low strain rate conditions, the effects of mixed-mode loading and high strain rates representative …


Experimental Insights Into Friction Losses Of Post-Tensioned Precast Full-Scale Girders, Mostafa Serry Dec 2024

Experimental Insights Into Friction Losses Of Post-Tensioned Precast Full-Scale Girders, Mostafa Serry

Theses and Dissertations

The use of post-tensioning in construction has revolutionized the construction industry and made way for several construction and structural applications that were unattainable before. One of the most important topics that are synonymous with the use of post-tensioning is the matter of accurately calculating the short-term and long-term losses that arise in pre-stress. One of the prominent types of losses is the friction losses that occur during the jacking of the concrete elements due to its impact on structural integrity and longevity.

The thesis examines this critical aspect of friction losses in post-tensioned concrete structures. The study focuses on full-scale, …


The State Of The City's Bridges, Leo G. Miranda Dec 2024

The State Of The City's Bridges, Leo G. Miranda

Capstones

An analysis by NYCity News Service of 2024 federal bridge inspection found that 118 segments of city bridges are in poor condition, around 8% of all bridges citywide. Among these are segments of major highways and bridges like the Brooklyn Queens Expressway, FDR Drive, Harlem River Drive, Grand Central Parkway and even a part of the iconic Brooklyn Bridge. On a single stretch of highway, where the Grand Central Parkway and the Whitestone Expressway meet in Queens, there are seven parts of highway or ramps in poor condition.

Bridge segments can be any raised roadway that passes over another parkway, …


Enhancing Civil Infrastructure Performance Through Lidar-Based Dynamic Monitoring And Phased-Construction Bridges, Khalid Hossam Alkady Dec 2024

Enhancing Civil Infrastructure Performance Through Lidar-Based Dynamic Monitoring And Phased-Construction Bridges, Khalid Hossam Alkady

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

This dissertation aims to enhance the performance and structural integrity of civil infrastructure systems through two primary goals. The first goal is to develop and rigorously validate end-to-end frameworks for full-field monitoring of the dynamic response of civil structures via Ground-based Lidar (GBL) scanners. GBL can be employed to sample point clouds at a high sampling rate for dynamic data collection, which addresses the limitations of using contact-based sensors in structural health monitoring (SHM) applications used for early-detection of structural damage.

The second goal of this dissertation concerns the challenges associated with constructing bridges in phases, so they can remain …


Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong Dec 2024

Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong

Architectural Engineering: Graduate Reports

The seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE. Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and …


Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk Dec 2024

Fitting Quality Of Nmr Relaxation Data To Differentiate Asphalt Binders, Rebecca M. Herndon, Kevin Lai, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binder performance grades (PGs) are important metrics in designing pavements for effective transportation infrastructure. the PG system relies on the binder's stiffness and is determined through energy- and time-intensive physical testing. Physical properties, like stiffness, can also be determined by spin–lattice NMR relaxometry, a non-destructive chemical method. NMR relaxometry can quantify the molecular mobility of materials by determining relaxation times from exponential decays of excited nuclear magnetization. While relaxation times have been used to determine physical properties of materials, a quantitative relation to the PG grades of asphalt binder is yet to be established. in this study, T1 NMR …


Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee Dec 2024

Deep Learning Vision-Based Bridge Inspection With Resource-Constrained Unmanned Aircraft Systems, Ji Young Lee

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

Bridge inspection is critical for ensuring structural integrity, extending the service life of infrastructure, and minimizing maintenance costs. As bridges age and endure increasing loads, regular inspections help detect early signs of wear, such as cracks or corrosion, that could impact safety and performance. However, traditional inspection methods are labor-intensive, requiring significant time, specialized equipment, and manual access to challenging areas, which can lead to costly disruptions. Additionally, reliance on human inspectors introduces subjectivity, with assessments varying by individual expertise. These factors highlight the inefficiencies and safety risks in current inspection practices, underscoring the need for more objective, efficient solutions. …


Anti-Corrosion Performance Of Magnesium Potassium Phosphate Cement Coating On Steel Reinforcement: The Effect Of Boric Acid, Fan Zhang, Jihui Qin, Kangyi Cai, John J. Myers, Hongyan Ma Nov 2024

Anti-Corrosion Performance Of Magnesium Potassium Phosphate Cement Coating On Steel Reinforcement: The Effect Of Boric Acid, Fan Zhang, Jihui Qin, Kangyi Cai, John J. Myers, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

It has recently been found that magnesium potassium phosphate cement (MKPC) paste coating applied on the surface of steel reinforcement can effectively retard the onset of corrosion and suppress corrosion reactions. However, the fast-setting nature of MKPC—which is a merit in repair—can be problematic in a practical engineering process of coating the steel reinforcement with MKPC paste. To address this problem, boric acid (H3BO3) was added as a retarder in an MKPC formulation to prolong the setting time. This work investigated the impact of boric acid (at 5% by weight of MgO) on the anti-corrosion performance …


The Influence Of Planning And Architectural Styles On The Sustainability Of The City Of Kumasi, Ghana, Elom Ayeke Oct 2024

The Influence Of Planning And Architectural Styles On The Sustainability Of The City Of Kumasi, Ghana, Elom Ayeke

Tanzania Journal of Engineering and Technology (TJET)

The city of Kumasi that was once dubbed the ‘Garden City of West Africa’ was founded in the late 17th century and served as the seat of government for the medieval Greater Asante Union. It later served as a commercial hub for the British Colony after undergoing massive transformation in the first two decades of the 19th century. Post-independence, the city went through various urban planning projects that mostly targeted social development. The architecture of Kumasi has also been changing through different periods of its history. This article examines the relationship between the evolution of the city of Kumasi through …


Relationship Between Historic Evolution, Urbanization And Mobility In Ibadan, Nigeria, Aisha Adams Oct 2024

Relationship Between Historic Evolution, Urbanization And Mobility In Ibadan, Nigeria, Aisha Adams

Tanzania Journal of Engineering and Technology (TJET)

Ibadan is said to be the biggest indigenous city in Nigeria with a population of about 4.04 million, making it the third largest city in the country after Lagos and Kano. Since its founding in 1829, Ibadan has experienced urban evolution that is mostly unguided. With its high fertility rate, population growth and rural-to-urban migration, Ibadan has experienced significant urban sprawl that has resulted in challenges in urban mobility especially to the lower-income earners. This study looks at the relationship between urban planning, urbanization and mobility in the city of Ibadan. The study found that lack of integrated land use …


Urbanization And Urban Sprawl In The Post-Colonial Era Douala City, Cameroon, Sylvia Munisi Oct 2024

Urbanization And Urban Sprawl In The Post-Colonial Era Douala City, Cameroon, Sylvia Munisi

Tanzania Journal of Engineering and Technology (TJET)

The history of the port city of Douala spans pre-colonial period, colonial period of the Germans and French occupation, the post-colonial era and the contemporary situation with continuous occupancy of the coastal environment. This article looks at the relationship between the history of the city of Douala to the resulting urban situation focusing on governance structure as well as rapid urbanization. The findings show that governance structure allowing for a duality of modern political system and traditional cultural system of kingships and chiefdoms has an effect to the resulting urban sprawl. Moreover, rapid urbanization under this condition has an overall …


The Use Of Locally Available Materials Towards Urban Planning For Sustainable Construction: The Case Of Gondar-Ethiopia, Kidist Dereje Oct 2024

The Use Of Locally Available Materials Towards Urban Planning For Sustainable Construction: The Case Of Gondar-Ethiopia, Kidist Dereje

Tanzania Journal of Engineering and Technology (TJET)

The city of Gondar in northern Ethiopia has a rich history that is connected to urban planning and construction. From the era of the Fasiledes that built masonry castles, Italian colonialism that zoned the city on racial boundaries and the post-colonial planning that wanted a more global standard, Gondar has been subjected to different planning and construction methods. This evolution however, has brought about challenges related to the sustainability of the construction industry and the communities within the city. This paper analyses the relationship between urban planning and use of local construction materials to attain sustainable development of the city. …


Transport Mobility Analysis For Informal Settlements In Dar Es Salaam, Tanzania, Fatma Kassim Mohamed Oct 2024

Transport Mobility Analysis For Informal Settlements In Dar Es Salaam, Tanzania, Fatma Kassim Mohamed

Tanzania Journal of Engineering and Technology (TJET)

Dar es Salaam is one of the world’s fastest growing cities and is expected to be the third largest by 2100 with a population of 76 million. Dar es Salaam city is made of multiple neighbourhoods that are very diverse in terms of socio-economic status, gender, age and prevalent activities. One of the biggest challenges facing the city of Dar es Salaam is urban sprawl due to informal settlements that in turn leads to very long travel time and hinders equal mobility and accessibility of labour and goods. This study found that the current mobility vision for Dar es Salaam …


Investigating The Relationship Between History, Urbanization And Wealth Gap In Johannesburg, South Africa, Abdallah F. Kaamah Oct 2024

Investigating The Relationship Between History, Urbanization And Wealth Gap In Johannesburg, South Africa, Abdallah F. Kaamah

Tanzania Journal of Engineering and Technology (TJET)

The city of Johannesburg is the largest city in South Africa and named as one of the economic drivers of the country. However, the city has the widest wealth gap in the country. This article examines the relationship between historical occurrences, urbanization, and the resulted wealth disparity in Johannesburg and look at the mitigation measures. The findings point to the wealth disparity in the city as a multifaceted problem influenced by historical, urbanization, and political variables. Comprehensive and multifaceted policy initiatives are required to address the structural causes of inequality and the urgent needs of vulnerable populations to close the …


Influence Of Concrete Jacketing On The Performance Of Steel Columns Under Blast Induced Progressive Collapse, Hanan Eltobgy Prof., Mohamed Saeed Refaey Dr., Mohamed Ahmed Aboshok Dr., Ahmed Emadel-Din Abdel-Aal Eng. Oct 2024

Influence Of Concrete Jacketing On The Performance Of Steel Columns Under Blast Induced Progressive Collapse, Hanan Eltobgy Prof., Mohamed Saeed Refaey Dr., Mohamed Ahmed Aboshok Dr., Ahmed Emadel-Din Abdel-Aal Eng.

Journal of Engineering Research

This study investigates the influence of concrete jacketing on the performance of steel columns subjected to blast loading, which can lead to progressive collapse. Using Finite Element Method (FEM) simulations, the research evaluates concrete-encased steel columns with different concrete cover thicknesses to measure their resistance to lateral displacements induced by blasts. Findings reveal that increasing the thickness of the concrete cover markedly improves the column's ability to withstand such loads. The study also highlights that steel has better energy dissipation properties than concrete. It examines how the combined challenges of progressive collapse and blast loading influence the overall structural response …


Experimental Investigation Of Light-Weight Concrete-Filled Stainless Steel Tube Composite Long Columns, Nadia Fath Alla, Kamel Kandeel, Mahmoud El-Nagar Oct 2024

Experimental Investigation Of Light-Weight Concrete-Filled Stainless Steel Tube Composite Long Columns, Nadia Fath Alla, Kamel Kandeel, Mahmoud El-Nagar

Journal of Engineering Research

The main target of this study is to investigate the behavior and performance of long composite circular stainless steel columns filled with light-weight concrete. An experimental study was carried out on four specimens, two of them are long composite circular stainless steel columns with length 1400 mm, diameter 100 mm and thickness of stainless steel tube 2 mm filled with light-weight and normal concrete with strengths 12 and 26 mpa respectively, which denoted by C1400/12 and C1400/26. The other two specimens are short composite circular stainless steel columns with length 500 mm, diameter 100 mm and thickness of stainless steel …


Seismic Resilience Of Timber Homes, Melia R. Costa Oct 2024

Seismic Resilience Of Timber Homes, Melia R. Costa

College of Engineering Summer Undergraduate Research Program

The vast majority of residential buildings in California are wood-frame structures. A home is typically a very large investment for families, and damage to the home can be detrimental to a family’s economic success. Thus, reducing the economic impacts of an earthquake on residential timber housing is crucial. A full scale, two-story section of a residential timber house is in construction in the Parson’s Geotechnical and Earthquake Engineering Laboratory on the Cal Poly campus in San Luis Obispo, California. Once built it will be put through earthquake simulation tests on a shake table with various magnitudes of seismic activity. Next, …


Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk Sep 2024

Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt pavements make up a majority of the essential transportation systems in the US. Asphalt mixtures age and degrade over time, reducing the pavement performance. Pavement performance critically depends on the aging of asphalt binder. The aging of asphalt binder during construction is traditionally modeled by rolling thin film oven (RTFO) testing, while aging during service life is modeled by pressure aging vessel (PAV) testing. Comparing these models to the aging of binders in actual pavements is limited because, to be used for current testing, binders must be separated from the pavement's aggregate by solvent extraction. Solvent extraction will, at …


Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk Sep 2024

Asphalt-Binder Mixtures Evaluated By T1 Nmr Relaxometry, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt pavements make up a majority of the essential transportation systems in the US. Asphalt mixtures age and degrade over time, reducing the pavement performance. Pavement performance critically depends on the aging of asphalt binder. the aging of asphalt binder during construction is traditionally modeled by rolling thin film oven (RTFO) testing, while aging during service life is modeled by pressure aging vessel (PAV) testing. Comparing these models to the aging of binders in actual pavements is limited because, to be used for current testing, binders must be separated from the pavement's aggregate by solvent extraction. Solvent extraction will, at …


Nuclear Magnetic Resonance (Nmr) Assessment Of Bio And Crude Oil-Based Rejuvenation, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk Sep 2024

Nuclear Magnetic Resonance (Nmr) Assessment Of Bio And Crude Oil-Based Rejuvenation, Rebecca M. Herndon, Jay Balasubramanian, Magdy Abdelrahman, Klaus Woelk

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Asphalt binders in pavements lose their stability through aging and eventually fail in the field. Using nuclear magnetic resonance (NMR) to monitor the primary longitudinal relaxation time of asphalt samples and the ratio of material that carries this primary relaxation time has been shown to indicate the impact of ultraviolet (UV) radiation on the aging of asphalt pavements. Longitudinal NMR relaxation was used to investigate two types of proposed asphalt rejuvenators, a bio-oil-based rejuvenator and a crude-oil-based rejuvenator. Two different binders with the performance grades (PG) 64-22 and 76-22 were considered for their interactions with the rejuvenators. After 72 h …