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Articles 841 - 870 of 7869

Full-Text Articles in Civil and Environmental Engineering

Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen Jul 2020

Synthesis And Characterization Of Free-Stand Graphene/Silver Nanowire/Graphene Nano Composite As Transparent Conductive Film With Enhanced Stiffness, Chuanrui Guo, Yanxiao Li, Yanping Zhu, Chenglin Wu, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As-grown graphene via chemical vapor deposition (CVD) has potential defects, cracks, and disordered grain boundaries induced by the synthesis and transfer process. Graphene/silver nanowire/graphene (Gr/AgNW/Gr) sandwich composite has been proposed to overcome these drawbacks significantly as the AgNW network can provide extra connections on graphene layers to enhance the stiffness and electrical conductivity. However, the existing substrate (polyethylene terephthalate (PET), glass, silicon, and so on) for composite production limits its application and mechanics behavior study. In this work, a vacuum annealing method is proposed and validated to synthesize the free-stand Gr/AgNW/Gr nanocomposite film on transmission electron microscopy (TEM) grids. AgNW …

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A Data-Driven Approach For Winter Precipitation Classification Using Weather Radar And Nwp Data, Bong Chul Seo Jul 2020

A Data-Driven Approach For Winter Precipitation Classification Using Weather Radar And Nwp Data, Bong Chul Seo

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study describes a framework that provides qualitative weather information on winter precipitation types using a data-driven approach. The framework incorporates the data retrieved from weather radars and the numerical weather prediction (NWP) model to account for relevant precipitation microphysics. To enable multimodel-based ensemble classification, we selected six supervised machine learning models: k-nearest neighbors, logistic regression, support vector machine, decision tree, random forest, and multi-layer perceptron. Our model training and cross-validation results based on Monte Carlo Simulation (MCS) showed that all the models performed better than our baseline method, which applies two thresholds (surface temperature and atmospheric layer thickness) for …

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Random Packing Material In Disinfection Contactors: Effects On Final Drinking Water Quality, Jessica L. Baker, Susan K. De Long, Subhas K. Venayagamoorthy Jul 2020

Random Packing Material In Disinfection Contactors: Effects On Final Drinking Water Quality, Jessica L. Baker, Susan K. De Long, Subhas K. Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the concern about biofilm growth on random packing material (RPM) used to enhance the hydraulic disinfection efficiency of a chlorine contactor. The inflow, outflow, and RPM were monitored for heterotrophic bacteria (via heterotrophic plate counts) and Pseudomonas aeruginosa as indicators of bacteriological water quality and the presence of biofilm. The results of this study show that there was no substantial biofilm growth in a lab-scale chlorine contactor and no substantial increase in bacterial counts for the bulk outflow over a 10-week period. Thus, the potential for excessive biofilm growth should not be considered a barrier concerning the …

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The Ethical Challenges Of Antimicrobial Resistance For Nurse Practitioners, Sarah Oerther, Daniel B. Oerther Jul 2020

The Ethical Challenges Of Antimicrobial Resistance For Nurse Practitioners, Sarah Oerther, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Antimicrobial resistance (AMR) is one of the most challenging worldwide health threats facing modern medicine (Centers for Disease Control, 2018; Logan & Bonomo, 2016; World Health Organization, 2018; Zerr et al., 2014). According to the World Health Organization (2018), when antimicrobial drugs are no longer effective at killing infections caused by bacteria, fungi, parasites and viruses, this is called AMR. AMR leads to drug-resistant infections (World Health Organization, 2018). Nurse practitioners need to be leaders in mitigating risks associated with antimicrobial use, including ethical dilemmas surrounding AMR (Centers for Disease Control, 2018; Logan & Bonomo, 2016; World Health Organization, 2018; …

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Final Report - Bridge Resilience Assessment With Inspire Data, Iris Tien, Yijian Zhang Jun 2020

Final Report - Bridge Resilience Assessment With Inspire Data, Iris Tien, Yijian Zhang

Project RR-1

This project proposed a methodology to assess the impact of corrosion on the performance of bridges. The combined analytical and numerical modeling of shear-critical and lap-spliced columns is detailed, and outcomes are verified with previous experimental test data. The impact of corrosion on risk is assessed through conducting fragility analyses. Results quantify the increase in failure probabilities of these structures, measured by increasing probabilities of exceeding defined damage states, with increasing levels of corrosion. Corrosion is found to have a larger impact on increasing probabilities of exceeding more severe damage states. Twenty percent mass loss of reinforcement increases the probability …

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Mobile Manipulating Drones, Paul Oh Jun 2020

Mobile Manipulating Drones, Paul Oh

INSPIRE Archived Webinars

In the past few years, robotic limbs have been attached to rotorcraft drones to perform aerial manipulation. Unlike simple object pick-and-place, such mobile-manipulating drones are dexterous to perform tasks like valve-turning, hatch-opening, and tool-handling. This is a paradigm shift where such drones actively interact with their environment rather than just passively surveil. Aerial manipulation is challenging because such interaction yields reaction forces and torques that destabilize the drone. This talk will provide an overview of aerial manipulation and showcase examples that could serve in infrastructure inspection, maintenance, and repair.

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Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha Jun 2020

Prediction Of Flotation Efficiency Of Metal Sulfides Using An Original Hybrid Machine Learning Model, Rachel Cook, Keitumetse Cathrine Monyake, Muhammad Badar Hayat, Aditya Kumar, Lana Alagha

Materials Science and Engineering Faculty Research & Creative Works

Froth flotation process is extensively used for selective separation of base metal sulfides from uneconomic mineral resources. Reliable prediction of process outcomes (metal recovery and grade) is vital to ensure peak performance. This work employs an innovative hybrid machine learning (ML) model—constructed by combining the random forest model and the firefly algorithm—to predict froth flotation efficiency of galena and chalcopyrite in relation to various experimental process parameters. The hybrid model's prediction performance was rigorously evaluated and compared against four different standalone ML models. The outcomes of this study illustrate that the hybrid ML model has the prediction ability to process …

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Utility Of Vertically Integrated Liquid Water Content For Radar-Rainfall Estimation: Quality Control And Precipitation Type Classification, Bong Chul Seo, Witold F. Krajewski, Youcun Qi May 2020

Utility Of Vertically Integrated Liquid Water Content For Radar-Rainfall Estimation: Quality Control And Precipitation Type Classification, Bong Chul Seo, Witold F. Krajewski, Youcun Qi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study proposes a new estimation method for vertically integrated liquid water content (VIL) using radar reflectivity volume data and temperature sounding retrieved from the numerical weather model analysis. This method addresses uncertainty factors in conventional VIL estimation associated with the effects from the bright band (BB) and radar beam geometry near the radar site. The new VIL is then used for precipitation classification (convective/stratiform) and wind turbine clutter detection in the hope that the estimated VIL indicating vertical activities or development of precipitation systems will account for the two independent subjects together, in opposite ways. The non-precipitation radar echoes …

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A System-Of-Systems Model To Simulate The Complex Emergent Behavior Of Vehicle Traffic On An Urban Transportation Infrastructure Network, Rayan Assaad, Cihan H. Dagli, Islam H. El-Adaway May 2020

A System-Of-Systems Model To Simulate The Complex Emergent Behavior Of Vehicle Traffic On An Urban Transportation Infrastructure Network, Rayan Assaad, Cihan H. Dagli, Islam H. El-Adaway

Engineering Management and Systems Engineering Faculty Research & Creative Works

Transportation agencies face escalating challenges in forecasting the traffic demand. Traditional prediction methods focused on individual transportation sectors and failed to study the inter-dependencies between the different transportation systems. Hence, there is a need for more advanced and holistic modeling techniques. To this end, this paper models and analyses an urban transportation system-of-systems incorporating seven various systems: population and GDP, CO2 emission, gasoline price and total vehicle trips, traffic demand, public and private transportation, transportation investment, and traffic congestion. Accordingly, this research simulates transportation networks as a collection of task-oriented systems that combine their resources to form a complex …

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A System Dynamics Approach For Study Of Population Growth And The Residential Housing Market In The Us, Gasser Galal Ali, Islam H. El-Adaway, Cihan H. Dagli May 2020

A System Dynamics Approach For Study Of Population Growth And The Residential Housing Market In The Us, Gasser Galal Ali, Islam H. El-Adaway, Cihan H. Dagli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The US Consensus bureau estimated the total construction spending at 1,320,305 Million Dollars, in February 2020, with an increase of 1.1% since last February. The construction market is large, and risky. Prediction of the market behavior, for several years ahead, is needed in order to take strategic investment decision for long and expensive projects. The goal of this research is to study the relationship between population growth and the housing market. To that end, a system dynamics model is developed. System dynamics is a top-down approach that starts with the high-level behavior of a complex system to simulate the behavior …

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A System Dynamics Model For Construction Safety Behavior, Mohamad Abdul Nabi, Islam H. El-Adaway, Cihan H. Dagli May 2020

A System Dynamics Model For Construction Safety Behavior, Mohamad Abdul Nabi, Islam H. El-Adaway, Cihan H. Dagli

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Construction Industry has always been reputed by its high incident rates and poor safety performance. Construction accidents are, in most cases, resulted from the unsafe behaviors of construction workers on site. The study of workers' behavior is crucial in order to understand the causation of unsafe behaviors. Therefore, the objective of this paper is to simulate construction safety behavior in order to predict the number of safety incidents and better understand their causation factors. The simulation model illustrates how construction system influences construction labors on site in terms of unsafe behavior. The standard leading indicators of safety performance are first …

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An Agent-Based Model To Study Competitive Construction Bidding And The Winner's Curse, Amr Elsayegh, Cihan H. Dagli, Islam H. El-Adaway May 2020

An Agent-Based Model To Study Competitive Construction Bidding And The Winner's Curse, Amr Elsayegh, Cihan H. Dagli, Islam H. El-Adaway

Engineering Management and Systems Engineering Faculty Research & Creative Works

Reverse auction theory is the basis for competitive construction bidding process. The lowest bid method is utilized for selecting contractors in public projects. The winning contractor having the lowest bid value could be cursed when the submitted bid value results in negative profits. This is caused by many factors such as the contractor's estimation accuracy and markup. This is addressed in this paper by providing a model simulating the construction competitive bidding and the occurrence of the winner's curse. To this end, the authors show the extent to which the winner's curse affects the status of contracting companies. The objectives …

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Experimental And Numerical Comparison Of Flexural Capacity Of Light Gage Cold Formed Steel Roof Deck, Christopher H. Raeel, Dawid Gwozdz May 2020

Experimental And Numerical Comparison Of Flexural Capacity Of Light Gage Cold Formed Steel Roof Deck, Christopher H. Raeel, Dawid Gwozdz

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

This paper presents an analysis of experimental data and compares it to two numerical analysis methods of light gage cold formed steel roof deck. The flexural capacity was determined upon the first failure mode of the light gage cold formed steel roof deck. A comparison of the experimental data was made to both the effective width method and the direct strength method. The objective of the comparison was to have a physical test provide the actual behavior of the light gage cold formed steel roof deck and grade how well the numerical analysis, effective width and direct strength methods, compare …

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Antimicrobial Resistance Needs To Be Combated At Primary Levels Of Prevention By Nurses, Sarah Oerther, Daniel B. Oerther May 2020

Antimicrobial Resistance Needs To Be Combated At Primary Levels Of Prevention By Nurses, Sarah Oerther, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

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Spherical Cavity Expansion Approach For The Study Of Rigid-Penetrator’S Impact Problems, Mario Buchely, Alejandro Marañon May 2020

Spherical Cavity Expansion Approach For The Study Of Rigid-Penetrator’S Impact Problems, Mario Buchely, Alejandro Marañon

Materials Science and Engineering Faculty Research & Creative Works

In recent years, Spherical Cavity Expansion (SCE) theory has been extensively utilized to model dynamic deformation processes related to indentation and penetration problems in many fields. In this review, the SCE theory is introduced by explaining the different mathematical features of this theory, its solution, and a potential application to model the penetration of a rigid penetrator into a deformable target. First, a chronologically literature review of the most common models used to study this kind of penetration problems is introduced, focusing on the SCE theory. Then, the engineering model of penetration is presented using the SCE approach. The model …

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Final Report - Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen, Haibin Zhang, Zhaochao Li Apr 2020

Final Report - Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen, Haibin Zhang, Zhaochao Li

Project SN-1

This project proposed an unmanned aerial vehicle (UAV)-based method to measure the change in magnetic field as a result of the movement of a smart rock to monitor the maximum depth of bridge scour. A high resolution 3-axis magnetometer and global positioning system (GPS) unit were installed on the UAV to obtain the magnetic field intensity and its corresponding coordinate. The optimization algorithm for the localization of smart rock was demonstrated and adopted. The impact factors on accurate smart rock positioning were experimentally investigated. Utilizing finite element method, the influence of steel reinforcing bars on the distribution of ambient magnetic …

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Final Report - In-Line Long Period Grating And Brillouin Scattering Fiber Optic Sensors For Strain, Temperature, Chloride Concentration, And Steel Mass Loss Measurement In Bridge Applications, Genda Chen, Chuanrai Guo Apr 2020

Final Report - In-Line Long Period Grating And Brillouin Scattering Fiber Optic Sensors For Strain, Temperature, Chloride Concentration, And Steel Mass Loss Measurement In Bridge Applications, Genda Chen, Chuanrai Guo

Project SN-3

This project developed an in-line grating and scattering fiber optic sensing system for strain, temperature, and steel mass loss measurement in bridge applications. Long period fiber gratings (LPFG) sensors are responsive to thermal and mechanical deformation, and the refractive index change of their surrounding medium. Brillouin scattering sensors are responsive to temperature and strain along an optical fiber. A CO2 laser aided fiber grating system was assembled for LPFG fabrication. To enable mass loss measurement, a low pressure chemical vapor deposition (LPCVD) system was built to synthesize a graphene/silver nanowire composite film as flexible transparent electrode for the electroplating of …

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The Challenge Of Calculating U-Factors For Cold-Formed Steel C-Shape Wall Assemblies Using Framing Factors, American Iron And Steel Institute Apr 2020

The Challenge Of Calculating U-Factors For Cold-Formed Steel C-Shape Wall Assemblies Using Framing Factors, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

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Development Of A U-Factor Calculation Procedure For Cold-Formed Steel C-Shaped Clear Wall Assemblies, American Iron And Steel Institute Apr 2020

Development Of A U-Factor Calculation Procedure For Cold-Formed Steel C-Shaped Clear Wall Assemblies, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

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Using Scrap Tires As An Aggregate In Chip Seal - Phase Ii, Alireza Pourhassan, Ahmed Gheni, Mohamed Elgawady Apr 2020

Using Scrap Tires As An Aggregate In Chip Seal - Phase Ii, Alireza Pourhassan, Ahmed Gheni, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Technical Reports

Chip seals are one of the most cost and performance effective pavement preservation treatments commonly used in the United States. An eco-friendly chip seal pavement, in which the natural aggregate was replaced by crumb rubber obtained from scrap tires, was recently developed by the research team at Missouri S&T, creating rubberized chip seal. This project investigated and optimized the performance of rubberized chip seal under different scenarios. During this project, laboratory chip seal specimens with different sizes were prepared and tested under simulated traffic loads with different loading parameters and environmental conditions. Also, the feasibility of the implementation and performance …

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Identifying Opportunities For Educators To Pursue Collaboration At The Interface Of Nursing And Engineering -- And A Word Of Caution, Daniel B. Oerther, Patricia Yoder-Wise, Beverly Malone Apr 2020

Identifying Opportunities For Educators To Pursue Collaboration At The Interface Of Nursing And Engineering -- And A Word Of Caution, Daniel B. Oerther, Patricia Yoder-Wise, Beverly Malone

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

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Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat Apr 2020

Correction To: Recommendations Of Rilem Tc 260-Rsc For Using Superabsorbent Polymers (Sap) For Improving Freeze–Thaw Resistance Of Cement-Based Materials (Materials And Structures, (2019), 52, 4, (75), 10.1617/S11527-019-1375-4), Viktor Mechtcherine, Christof Schröfl, Michaela Reichardt, Agnieszka J. Klemm, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Agnieszka J. Klemm is affiliated to Glasgow Caledonian University, Glasgow, UK.

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Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys Apr 2020

Estimation Of Lubrication Layer Thickness And Composition Through Reverse Engineering Of Interface Rheometry Tests, Alexis Salinas, Dimitri Feys

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

During concrete pumping, a lubrication layer is formed near the pipe wall. Extensive research has been performed on measuring and modeling the properties of this layer and using these values to predict pumping pressures. However, there are numerous discussions in the literature about the composition and thickness of this layer: can it be considered mortar, a micromortar, or is it cement paste? In this paper, possible solutions for the thickness and composition of the lubrication layer are derived from interface rheometry tests. It is assumed that the lubrication layer is composed of one or more concentric layers of paste or …

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Final Report - Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh, Blake Hament, Dongbin Kim Mar 2020

Final Report - Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh, Blake Hament, Dongbin Kim

Project AS-1

A parallel mechanism and smart gripper were designed and mounted on a rotorcraft drone to act as a robotic arm and hand. This empowers the drone to perform aerial manipulation and execute bridge maintenance. Hosing, drilling, and epoxying serve as case studies to test-and-evaluation and verify-and-validate the design. The approach, tasks, and findings are presented and show that the case studies are realizable. Conclusions and recommendations point to employing haptics-based human-in-the-loop approaches that can increase the scope of repair work involved in bridge maintenance

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Final Report - Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil K. Agrawal, Jizhong Xiao Mar 2020

Final Report - Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil K. Agrawal, Jizhong Xiao

Project IM-2

Impact sounding has been recognized as an effective technique to detect delamination in concrete structures, such as concrete decks. An enormous amount of sounding data can be generated/collected by the autonomous inspection systems equipped with impactors and microphones. However, the main challenge in the practical application of this technology is the development of advanced data analysis approaches for identifying defects from impact sounding data. In this study, the empirical mode decomposition (EMD) analysis and power-spectral density (PSD) analysis are combined to extract useful features of sounding data generated by the impact hammer. It has been found that the EMD method …

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Non-Contact Air-Coupled Sensing For Rapid Evaluation Of Bridge Decks, Jinying Zhu Mar 2020

Non-Contact Air-Coupled Sensing For Rapid Evaluation Of Bridge Decks, Jinying Zhu

INSPIRE Archived Webinars

Elastic wave-based non-destructive testing (NDT) methods are commonly used for evaluation of civil engineering infrastructure, including bridges, dams and buildings. However, most of these methods require coupling (direct contact) between sensors and the test surface, which significantly restricts the testing speed and consistency, especially for large scale concrete structures in civil engineering. The air-coupled sensing technology was developed by Dr. Jinying Zhu as a solution for rapid scanning of concrete infrastructure. In this webinar, Dr. Zhu will review the development of air-coupled sensing technique for civil engineering applications, including fundamental theory and field application of air-coupled sensing on concrete structures. …

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Interfacial Shear Bond Strength Between Steel H-Piles And Polymer Concrete Jackets, Mohanad M. Abdulazeez, Kyle Brown, Mohamed Elgawady Mar 2020

Interfacial Shear Bond Strength Between Steel H-Piles And Polymer Concrete Jackets, Mohanad M. Abdulazeez, Kyle Brown, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Steel H-piles have been used widely in bridge construction throughout the U.S. because of their relatively large load-carrying capacity while occupying a small area. However, many H-piles suffer from corrosion, which may lead to abrupt collapse. A cost-effective repair technique, including encasing the corroded region of the steel pile into a concrete jacket, which acts as an alternative load path for the applied axial load, has been used by several state Departments of Transportation. Methyl methacrylate polymer concrete (MMA-PC) is a type of concrete that is commonly used as a repair material. However, there is limited research on the assessment …

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Understanding Transport Of An Elastic, Spherical Particle Through A Confining Channel, Shuaijun Li, Honghui Yu, Tai-De Li, Zi Chen, Wen Deng, Alimohammad Anbari, Jing Fan Mar 2020

Understanding Transport Of An Elastic, Spherical Particle Through A Confining Channel, Shuaijun Li, Honghui Yu, Tai-De Li, Zi Chen, Wen Deng, Alimohammad Anbari, Jing Fan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The transport of soft particles through narrow channels or pores is ubiquitous in biological systems and industrial processes. On many occasions, the particles deform and temporarily block the channel, inducing a built-up pressure. This pressure buildup often has a profound effect on the behavior of the respective system; yet, it is difficult to be characterized. In this work, we establish a quantitative correlation between the built-up pressure and the material and geometry properties through experiments and mechanics analysis. We fabricate microgels with a controlled diameter and elastic modulus by microfluidics. We then force them to individually pass through a constrictive …

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Corrosion-Induced Mass Loss Measurement Under Strain Conditions Through Gr/Agnw-Based, Fe-C Coated Lpfg Sensors, Chuanrui Guo, Liang Fan, Genda Chen Mar 2020

Corrosion-Induced Mass Loss Measurement Under Strain Conditions Through Gr/Agnw-Based, Fe-C Coated Lpfg Sensors, Chuanrui Guo, Liang Fan, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this study, graphene/silver nanowire (Gr/AgNW)-based, Fe-C coated long period fiber gratings (LPFG) sensors were tested up to 72 hours in 3.5 w.t% NaCl solution for corrosion-induced mass loss measurement under four strain levels: 0, 500, 1000 and 1500 µ∈. The crack and interfacial bonding behaviors of laminate Fe-C and Gr/AgNW layer structures were characterized using Scanning Electron Microscopy (SEM) and electrical resistance measurement. Both optical transmission spectra and electrical impedance spectroscopy (EIS) data were simultaneously measured from each sensor. Under increasing strains, transverse cracks appeared first and were followed by longitudinal cracks on the laminate layer structures. The spacing …

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Dislocation-Oxide Interaction In Y2o3 Embedded Fe: A Molecular Dynamics Simulation Study, M. Mustafa Azeem, Qingyu Wang, Zhongyu Li, Yue Zhang Feb 2020

Dislocation-Oxide Interaction In Y2o3 Embedded Fe: A Molecular Dynamics Simulation Study, M. Mustafa Azeem, Qingyu Wang, Zhongyu Li, Yue Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Oxide dispersed strengthened (ODS) steel is an important candidate for Gen-IV reactors. Oxide embedded in Fe can help to trap irradiation defects and enhances the strength of steel. It was observed in this study that the size of oxide has a profound impact on the depinning mechanism. For smaller sizes, the oxide acts as a void; thus, letting the dislocation bypass without any shear. On the other hand, oxides larger than 2 nm generate new dislocation segments around themselves. The depinning is similar to that of Orowan mechanism and the strengthening effect is likely to be greater for larger oxides. …

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