Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Missouri University of Science and Technology

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 991 - 1020 of 21777

Full-Text Articles in Engineering

The Effectiveness Of Waste Tire Pyrolysis Oils (Wtpos) As Rejuvenating Agents For Asphalt Materials, Ahmed S. El-Ashwah, Magdy Abdelrahman Aug 2024

The Effectiveness Of Waste Tire Pyrolysis Oils (Wtpos) As Rejuvenating Agents For Asphalt Materials, Ahmed S. El-Ashwah, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The continuous increase in solid waste materials, such as waste tires, underscores the critical importance of recycling them to mitigate environmental impact and promote sustainable resource management. This research study evaluated the effectiveness of utilizing waste tire pyrolysis oils (WTPOs) as recycling agents for asphalt materials. The chemical composition and thermal behavior of WTPO were analyzed using Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). Mechanically, the prepared WTPO binders were assessed by measuring dynamic viscosity and changes in high- and intermediate-temperature performance grades. Additionally, the cracking susceptibility of the binders was evaluated using the Glover-Rowe (G-R) parameter. The …


Quantifying The Impact Of Technology Utilization On Schedule And Cost Performance In Construction Projects, Fareed Salih, Islam H. El-Adaway Aug 2024

Quantifying The Impact Of Technology Utilization On Schedule And Cost Performance In Construction Projects, Fareed Salih, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

There Has Been a Plethora of Research on the Performance of Schedule and Cost in Construction Projects. However, Current Research Falls Short in Investigating the Combined Contribution of Different Construction Technologies on Project Performance Metrics. Specifically, None of the Previous Efforts Have Used Integrated Earned Value Management (EVM) Parameters and Utilized Construction Technologies to Assess Project Schedule and Cost Performance. This Paper Fills This Knowledge Gap. to This End, a Multistep Research Methodology Was Employed to (1) Explore the Utilization Ratings of 13 Construction Technologies based on Data Collected from 52 Industry Experts; (2) Rank These Technologies in Terms of …


Rheology Modification Of Flowable Mortar With Co2, Sean Monkman, Soo Duck Hwang, Kamal Khayat Aug 2024

Rheology Modification Of Flowable Mortar With Co2, Sean Monkman, Soo Duck Hwang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Rheological Properties of Mortar Samples with Different Additions of CO2 during Mixing Were Determined. Flowable Cement-Based Mortars at Three Different W/c (0.55, 0.45 and 0.35) Were Produced and the Effects of CO2 Gas Were Examined on the Fresh Properties of Slump Flow, Yield Stress and Plastic Viscosity. According to the Experimental Results, the Mortar Yield Stress and Plastic Viscosity Increased Faster over Time Than in a Reference System with the Increasing Addition of CO2 and Greater Effects Were Seen at the Lowest W/c of 0.35 Than at the Others. the Impact of the CO2 on …


Accelerating The Circular Economy Transition: A Construction Value Chain-Structured Portfolio Of Strategies And Implementation Insights, Radwa Eissa, Islam H. El-Adaway Aug 2024

Accelerating The Circular Economy Transition: A Construction Value Chain-Structured Portfolio Of Strategies And Implementation Insights, Radwa Eissa, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Despite the Increasing Recognition of the Potential of Circular Economy (CE) Strategies, their Effective Application to Decarbonize the Construction Value Chain Faces Multiple Challenges. Ambiguity Surrounding CE, stemming from a Lack of Clarity on Actionable Strategies, is a Common Concern. Existing Studies Lack a Holistic Approach for Systematically Integrating CE Principles throughout the Construction Value Chain, resulting in a Scarcity of Information on How to Practically Adopt CE within Projects. This Research Aims to Accelerate CE Adoption by Creating a Value Chain-Structured Portfolio of CE Strategies and Analyzing the Implementation of Such Strategies in Actual Projects. to This End, a …


Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer Aug 2024

Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. the purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. the automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …


Tellurium Enrichment In Copper Tailings: A Mineralogical And Processing Study, José L. Corchado-Albelo, Lana Alagha Aug 2024

Tellurium Enrichment In Copper Tailings: A Mineralogical And Processing Study, José L. Corchado-Albelo, Lana Alagha

Mining Engineering Faculty Research & Creative Works

As the global demand for tellurium (Te) increases, it is crucial to develop efficient recovery methods that consider existing supply streams. This research combines gravity separation and froth flotation processes to enhance the recovery of Te minerals from tailings produced during the beneficiation of copper porphyry ores. Prior to processing, a systematic and comprehensive characterization study of copper tailing (CT) samples was conducted to examine the deportment of Te minerals in different mineral phases and to understand their locking and liberation behavior. Characterization techniques included inductively coupled plasma mass spectrometry (ICP-MS) and TESCAN's integrated mineral analysis (TIMA). Copper tailing characterization …


Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer Aug 2024

Meteorological Data Mining And Synthesis For Supplementing On-Site Data For Regulatory Compliance, Ben Sonpon, Shoaib Usman, Joseph Smith, Sarah Kovaleski, Jason Wibbenmeyer

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Many regulatory requirements add significant delay in the licensing of new nuclear power stations. One area of particular interest is the environmental impact of potential atmospheric release. The purpose of this research is to demonstrate effectiveness of meteorological data mining and synthesis from offsite locations to reduce need for onsite data, hence allowing rapid licensing. The automated procedures tested for data mining and extraction of meteorological data from multiple offsite sources and the data analytic tool developed for data fusion are presented here. Three important meteorological parameters from regulatory compliance are considered for this analysis: wind velocity, wind direction, and …


Design And Development Of Uio-67-Coated Pim-1-Based Composites And Demonstration Of Their Detoxification Performance, Sukanta K. Mondal, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei Aug 2024

Design And Development Of Uio-67-Coated Pim-1-Based Composites And Demonstration Of Their Detoxification Performance, Sukanta K. Mondal, Peter O. Aina, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Polymer-supported MOF composites have emerged as versatile candidates for various separation and catalytic applications. In this study, we demonstrate design and development of UiO-67-coated Ce(OH)4@PIM-1 composites via dip-coating, drop-casting, solid-phase coating, and supramolecular assembly, and assess their preparation-structure-performance relations. The catalytic performance of the composites was investigated through hydrolysis of dimethyl 4-nitrophenyl phosphate (DMNP), as a nerve agent simulant. The findings revealed that while dip-coating method was unable to achieve a thick and uniform coverage of the MOF layer on the Ce(OH)4@PIM-1, the supramolecular assembly gave rise to 16 wt.% MOF loading and the composite prepared …


Examination And Improvement Of The Taguchi-Based Nanofluids Impact On Co2 Absorption Using Al2o3 Nanoparticles, Safa Waleed Shakir, Saif Saleh Hussein, Shaymaa Hasan Khazaal, Hyder Akram Al-Naseri, Ahmed Mohammed Ahmed, Rana Najah Hachim, Muthanna Hikmat Al-Dahhan Aug 2024

Examination And Improvement Of The Taguchi-Based Nanofluids Impact On Co2 Absorption Using Al2o3 Nanoparticles, Safa Waleed Shakir, Saif Saleh Hussein, Shaymaa Hasan Khazaal, Hyder Akram Al-Naseri, Ahmed Mohammed Ahmed, Rana Najah Hachim, Muthanna Hikmat Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study, a batch absorption reactor was used to evaluate the nanofluid of a binary aqueous solution of monoethanolamine and 2-amino-2-methyl-1-propanol (MEA/AMP) with nanoparticles of aluminium oxide (Al2O3) as a solvent used to remove carbon dioxide (CO2) from simulated flue gas. Furthermore, the application of the Taguchi experiment design method determined the optimal conditions for the absorption process. This research focuses on the CO2 absorption process and the optimal conditions related to nanoparticle addition. The main effects of using nanofluid were investigated. The concentration of nanoparticles, nanoparticle size, and stirrer speeds were …


Heat Treatment Post-Processing For The Improved Mechanical Properties Of Scalmalloy® Processed Via Directed Energy Deposition, Rachel Boillat-Newport, Sriram Praneeth Isanaka, Frank Liou Aug 2024

Heat Treatment Post-Processing For The Improved Mechanical Properties Of Scalmalloy® Processed Via Directed Energy Deposition, Rachel Boillat-Newport, Sriram Praneeth Isanaka, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

As high-strength aluminum alloys present several processability issues with additive manufacturing (AM), Scalmalloy®, an Al-Mg-Sc-Zr-based alloy, has been developed. This alloy is age-hardenable, allowing it to precipitate out a strengthening precipitate phase, Al3(Sc,Zr). The manufacturer recommends a single-stage aging treatment at 325 °C for 4 h; however, the majority of the literature studies utilize a powder bed processing known as selective laser melting (SLM) over powder-fed processing directed energy deposition (DED). This study addresses the lack of information on heat treatments for DED fabrication by exploring the application of artificial aging temperatures of 300–400 °C for 2, 4, and 6 …


Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma Aug 2024

Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma

Economics Faculty Research & Creative Works

The electricity market crisis, driven by factors such as increased energy demand, rising fuel prices, aging infrastructure, and greenhouse gas emissions, requires a multifaceted approach including the strategic implementation of Carbon Capture and Storage (CCS) technologies, which despite high costs and potential adverse impact on renewable investments, can allow the use of fossil fuels to maintain grid stability, and simultaneously lower carbon footprint. Across the world, several nations are designing financial incentives and improving regulatory frameworks to reduce barriers to the deployment of CCS. However, it is not clearly understood whether and to what extent such policy support would affect …


Tectonic Implications Of Seismic Anisotropy Layering Beneath The Southern Tibetan Plateau Revealed By Integrated Shear Wave Splitting And Receiver Function Analyses, Cong Shen, Stephen S. Gao, Fansheng Kong, Kelly H. Liu Aug 2024

Tectonic Implications Of Seismic Anisotropy Layering Beneath The Southern Tibetan Plateau Revealed By Integrated Shear Wave Splitting And Receiver Function Analyses, Cong Shen, Stephen S. Gao, Fansheng Kong, Kelly H. Liu

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

To investigate continental dynamics underneath the south-central Tibetan plateau, which composes the Himalayan, Lhasa, and Qiangtang blocks, we have conducted comprehensive examinations of seismic azimuthal anisotropy in the crust using receiver functions (RFs) and crustal and mantle anisotropy using teleseismic shear wave splitting (SWS) analysis. In the Qiangtang block, the observed predominantly E-W fast orientations from RF and SWS analyses with similar magnitude are interpreted as resulting from eastward crustal flow with minor contributions from the mantle. In the Lhasa block, the crustal anisotropy is approximately N-S oriented, which is parallel to the strike of rift basins and southward crustal …


Influence Of Aggregate Properties On Skid Resistance Of Pavement Surface Treatments, Alireza Roshan, Magdy Abdelrahman Aug 2024

Influence Of Aggregate Properties On Skid Resistance Of Pavement Surface Treatments, Alireza Roshan, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Skid resistance is a critical aspect for traffic safety since it significantly influences vehicle control and minimizes the distance required for emergency braking. The surface characteristics of pavements play a pivotal role in determining skid resistance. To achieve the optimal skid resistance performance, the pavement must sustain a specific level of friction. Thus, it is advantageous to apply surface treatments in areas that require enhanced friction. This study investigates the impact of factors such as the aggregate source, size, morphological properties, and abrasion levels on the skid resistance and frictional characteristics of a high-friction surface treatment (HFST). A complete investigation …


Indefinability Of Effective Stress For Unsaturated Soils, Xiong Zhang, Sandra Houston Aug 2024

Indefinability Of Effective Stress For Unsaturated Soils, Xiong Zhang, Sandra Houston

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For decades, researchers have searched for an unsaturated soil effective stress that performs analogously to effective stress for saturated soils and provides some simplifications over net stress and suction approaches. A recent debate is whether problems identified with unsaturated soil effective stress can be resolved via elastoplastic analyses. Effective stress equations are reviewed and categorized as being based on volume change, shear strength, yield, or degree of saturation. These equations are evaluated for consistency with saturated soil effective stress expectations using the Barcelona basic model (BBM), simplified into an integrated elastoplastic framework using the modified state surface approach (MSSA). Under …


Determination Of Binary Co2/H2 Adsorption Isotherms And Kinetics Over Porous Organic Cage Cc3 Via Zero-Length Column Technique, Jimmy D.L. Moreno, Kyle Newport, Ali A. Rownaghi, Fateme Rezaei Aug 2024

Determination Of Binary Co2/H2 Adsorption Isotherms And Kinetics Over Porous Organic Cage Cc3 Via Zero-Length Column Technique, Jimmy D.L. Moreno, Kyle Newport, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

Understanding the dynamics of mixed-gas adsorption is essential for industrial-scale adsorptive separations. Also, obtaining binary adsorption isotherms is essential to gain a better understanding of adsorbate-adsorbent interactions in multicomponent gas mixtures. Porous organic cages (POCs) are highly porous, crystalline materials, with a small average pore window that make them promising candidates for separation applications. In this work, we utilized zero-length column (ZLC) technique to not only determine the kinetics of CO2/H2 separation over CC3 but also obtain the binary adsorption isotherms. The ultra crystalline diffusivities of 1.49 x 10–4 and 8.31 x 10–5 cm2 …


Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma Aug 2024

Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma

Economics Faculty Research & Creative Works

The electricity market crisis, driven by factors such as increased energy demand, rising fuel prices, aging infrastructure, and greenhouse gas emissions, requires a multifaceted approach including the strategic implementation of Carbon Capture and Storage (CCS) technologies, which despite high costs and potential adverse impact on renewable investments, can allow the use of fossil fuels to maintain grid stability, and simultaneously lower carbon footprint. Across the world, several nations are designing financial incentives and improving regulatory frameworks to reduce barriers to the deployment of CCS. However, it is not clearly understood whether and to what extent such policy support would affect …


Modeling Powder Spreadability In Powder-Based Processes Using The Discrete Element Method, Austin T. Sutton, M. Hossein Sehhat, Ming C. Leu, Joseph W. Newkirk Jul 2024

Modeling Powder Spreadability In Powder-Based Processes Using The Discrete Element Method, Austin T. Sutton, M. Hossein Sehhat, Ming C. Leu, Joseph W. Newkirk

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Powder-bed fusion (PBF) processes refer to a subset of Additive Manufacturing (AM) techniques where powder is spread on the build-plate before melting (by a laser or electron beam). While PBF processes are attractive due to their ability for realizing complex structures that are either difficult or impossible to create through conventional means, the parts fabricated with these techniques can exhibit defects such as pores, inclusions, and excessive surface roughness. To minimize these defects, much research has been dedicated towards process maturation by optimizing laser or electron beam parameters. However, these developmental efforts typically do not address the recoating process where …


Examining The Oxidation States Of Metals In Aerosols Emitted By Electronic Cigarettes, Kashala Fabrice Kapiamba, Stephen Yaw Owusu, Yangtao Wu, Yue-Wern Huang, Yi Jiang, Yang Wang Jul 2024

Examining The Oxidation States Of Metals In Aerosols Emitted By Electronic Cigarettes, Kashala Fabrice Kapiamba, Stephen Yaw Owusu, Yangtao Wu, Yue-Wern Huang, Yi Jiang, Yang Wang

Biological Sciences Faculty Research & Creative Works

Electronic cigarettes (ECs) emit many toxic substances, including metals, that can pose a threat to users and the environment. The toxicity of the emitted metals depends on their oxidation states. Hence, this study examines the oxidation states of metals observed in EC aerosols. X-ray photoelectron spectroscopy analysis of the filters that collected EC aerosols identified the oxidation states of five primary metals (based on surface sample analysis), including chromium(III) (close to 100%) under low power setting while a noticeable amount of chromium(VI) (15%) at higher power settings of the EC, and copper(II) (100%), zinc(II) (100%), nickel(II) (100%), lead(II) (65%), and …


Hybrid Mechanism Of Electrical Breakdown In Ferroelectric Materials Under High-Pressure Shock Loading, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase, Christopher S. Lynch Jul 2024

Hybrid Mechanism Of Electrical Breakdown In Ferroelectric Materials Under High-Pressure Shock Loading, Sergey I. Shkuratov, Jason Baird, Vladimir G. Antipov, Jay B. Chase, Christopher S. Lynch

Mining Engineering Faculty Research & Creative Works

The unique ability of ferroelectrics to generate high voltage under shock loading is limited by electrical breakdown within the shock-compressed ferroelectric material. Breakdown is a hybrid process of initiation and growth. The possible mechanisms of electrical breakdown in ferroelectric films and bulk ceramics subjected to high-pressure shock loading are discussed and experiments designed to elucidate which mechanisms govern breakdown. Gigapascal shock loading experiments were performed on poled Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 ferroelectric film specimens in the range of 32-156 μm thickness to determine the dependence of the breakdown field on thickness and …


Development Of Multivariate-Coupled Grouting Diffusion Model For Rcc, Xiao Sun, Yao Wang, Hengrui Liu, Zhuanjia Yang, Hongyan Ma Jul 2024

Development Of Multivariate-Coupled Grouting Diffusion Model For Rcc, Xiao Sun, Yao Wang, Hengrui Liu, Zhuanjia Yang, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Grouting Quality of Grout-Enriched Roller Compacted Concrete (RCC) is Difficult to Be Quantified Due to the Fact that the Crucial Effects, Such as Infiltration and the Compaction of the Skeleton of the RCC, Are Not Taken into Consideration. Combined with Model Testing, This Study Proposes an Improved Grouting Prediction Model Which Considers the Coupling Effect of Pore Fractal Properties, Time Variation of Grout Rheological Properties and Infiltration. Moreover, the Influence of Construction Parameters Such as Grouting Parameters, Construction Period Selection, Grouting Pipe Arrangement on the Grouting Effect Was Clarified. the Tests Indicated that the Maximum Diffusion Range of Slurry …


Early Detection Of Pipeline Natural Gas Leakage From Hyperspectral Imaging By Vegetation Indicators And Deep Neural Networks, Pengfei Ma, Tarutal Ghosh Mondal, Zhenhua Shi, Mohammad Hossein Afsharmovahed, Kevin Romans, Liujun Li, Ying Zhuo, Genda Chen Jul 2024

Early Detection Of Pipeline Natural Gas Leakage From Hyperspectral Imaging By Vegetation Indicators And Deep Neural Networks, Pengfei Ma, Tarutal Ghosh Mondal, Zhenhua Shi, Mohammad Hossein Afsharmovahed, Kevin Romans, Liujun Li, Ying Zhuo, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The timely detection of underground natural gas (NG) leaks in pipeline transmission systems presents a promising opportunity for reducing the potential greenhouse gas (GHG) emission. However, existing techniques face notable limitations for prompt detection. This study explores the utility of Vegetation Indicators (VIs) to reflect vegetation health deterioration, thereby representing leak-induced stress. Despite the acknowledged potential of VIs, their sensitivity and separability remain understudied. In this study, we employed ground vegetation as biosensors for detecting methane emissions from underground pipelines. Hyperspectral imaging from vegetation was collected weekly at both plant and leaf scales over two months to facilitate stress detection …


Exploring Equity, Diversity, And Inclusion In Computer Science Undergraduate Curricula, Ouldooz Baghban Karimi, Giulia Toti, Fiona Mcneill, Alice Gao, Rutwa Engineer, Shanon Reckinger, Peggy Lindner, Jinyoung Hur, Rebecca Robinson, Anna Sollazzo, Richard Wicentowski Jul 2024

Exploring Equity, Diversity, And Inclusion In Computer Science Undergraduate Curricula, Ouldooz Baghban Karimi, Giulia Toti, Fiona Mcneill, Alice Gao, Rutwa Engineer, Shanon Reckinger, Peggy Lindner, Jinyoung Hur, Rebecca Robinson, Anna Sollazzo, Richard Wicentowski

Engineering Management and Systems Engineering Faculty Research & Creative Works

One of the less explored approaches to foster equity, diversity, and inclusion (EDI) in Computer Science (CS) is through changes to the curriculum. Despite sporadic work on the adoption of Culturally Responsive Computing (CRC) and Universal Design for Learning (UDL), the inclusion of equity-minded courses, or modifications on specific elements of the curriculum such as introductory programming courses, there has never been a wide exploration or adoption of a successful equity-minded undergraduate CS curriculum. In this work, we explore undergraduate CS curricula, with a special focus on upper division, lower division, and service courses (courses offered to non-CS students). For …


Experimental Study On The Detection Of The Existence And Location Of Mimicked And Unexpected Interface Debonding Defects In An Existing Rectangular Cfst Column With Pzt Materials, Qian Liu, Bin Xu, Genda Chen, Weilong Ni, Zhixun Liu, Chun Lin, Zhiyou Zhuang Jul 2024

Experimental Study On The Detection Of The Existence And Location Of Mimicked And Unexpected Interface Debonding Defects In An Existing Rectangular Cfst Column With Pzt Materials, Qian Liu, Bin Xu, Genda Chen, Weilong Ni, Zhixun Liu, Chun Lin, Zhiyou Zhuang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Interface bonding conditions between concrete and steel materials play key roles in ensuring the composite effect and load-carrying capacity of concrete–steel composite structures such as concrete-filled steel tube (CFST) members in practice. A method using both surface wave and electromechanical impedance (EMI) measurement for detecting the existence and the location of inaccessible interface debonding defects between the concrete core and steel tube in CFST members using piezoelectric lead zirconate titanate (PZT) patches as actuators and sensors is proposed. A rectangular CFST specimen with two artificially mimicked interface debonding defects was experimentally verified using PZT patches as the actuator and sensor. …


Form Pressure Exerted By Concrete For A Large-Scale Structure: Its Quantification And Physicochemical Interpretation, Tae Yong Shin, Seongho Han, Jin Hyun Lee, Jae Hong Kim Jul 2024

Form Pressure Exerted By Concrete For A Large-Scale Structure: Its Quantification And Physicochemical Interpretation, Tae Yong Shin, Seongho Han, Jin Hyun Lee, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Securing safety in formwork is one of the most important tasks to be carried out in the initial stage of construction. The form pressure exerted by fresh concrete needs to be identified, and it should be retained by a formwork system. A design pressure is given in literature and standards, but for large structures its precise prediction is required through a detailed analysis or a mock-up test. This study reports the lateral form pressure distribution generated by fresh concrete through a series of mock-up tests. The tests are designed considering the placement for nuclear containment structures; 3.4 m tall and …


Theoretical Semi-Quantitative Risk Assessment Methodology For Tunnel Design And Construction Processes, Ozgur Satici, Esra Satici Jul 2024

Theoretical Semi-Quantitative Risk Assessment Methodology For Tunnel Design And Construction Processes, Ozgur Satici, Esra Satici

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

All engineering projects involve risk management applications. Sometimes, risks cannot be effectively managed, leading to catastrophic consequences. Engineers must consciously or unconsciously manage these risks. Regardless of how risks are handled, project risks need to be systematically evaluated. Therefore, risk management procedures must be implemented in every project, particularly in geo-engineering projects, to mitigate undesirable consequences and achieve project objectives. However, the use of risk management procedures in underground excavation projects is not common. Numerous commonly employed underground excavation techniques lack assessment of risks, notably geotechnical risks. Most of them only evaluate rock structures and excavation stability in accordance with …


Synergetic Effect Of Viscosity Modifying Admixtures And Polycarboxylate Ether Superplasticizer On Key Characteristics Of Thixotropic Uhpc For Bonded Bridge Deck Overlay Rehabilitation, Le Teng, Ming Jin, Jiadi Du, Kamal H. Khayat Jul 2024

Synergetic Effect Of Viscosity Modifying Admixtures And Polycarboxylate Ether Superplasticizer On Key Characteristics Of Thixotropic Uhpc For Bonded Bridge Deck Overlay Rehabilitation, Le Teng, Ming Jin, Jiadi Du, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Thin bonded ultra-high-performance concrete (UHPC) overlay is an advanced technology for bridge deck rehabilitation. UHPC should be tailored to secure adequate flowability and high thixotropy to facilitate mixing and placement with a low risk of sagging of the material on sloped bridge deck surfaces. The synergetic effect between nano clay (NC) and polycarboxylate ether (PCE) superplasticizer or cellulose-based viscosity modifying admixture (VMA) and PCE on the rheological properties (yield stress, plastic viscosity, and thixotropy), cement hydration, autogenous shrinkage, compressive strength, and porosity was systematically investigated. The bond strength between conventional concrete (CC) representing existing bridge deck concrete and thixotropic UHPC …


Optical Frequency Domain Reflectometry-Based High-Performance Distributed Sensing Empowered By A Data And Physics-Driven Neural Network, Zhaopeng Zhang, Wei Peng, Osamah Alsalman, Lingmei Ma, Jie Huang, Chen Zhu Jul 2024

Optical Frequency Domain Reflectometry-Based High-Performance Distributed Sensing Empowered By A Data And Physics-Driven Neural Network, Zhaopeng Zhang, Wei Peng, Osamah Alsalman, Lingmei Ma, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Optical frequency domain reflectometry (OFDR) based distributed strain sensors are the preferred choice for achieving accurate strain measurements over extensive sensing ranges while maintaining exceptional spatial resolution. However, the simultaneous realization of high spatial resolution, high strain resolution, large strain range, and an extended sensing range presents an exceedingly challenging endeavor. In this study, we introduce and experimentally demonstrate a data and physics-driven neural network-empowered OFDR system designed to attain high-performance distributed sensing. In our experiments, we successfully maintained an impressive sensing resolution of sub-microstrain (0.91 µε) alongside a sharp spatial resolution of sub-millimeter (0.857 mm) across a 140-m sensing …


A Study Of Directionality Effects In Three-Beam Coaxial Titanium Wire-Based Laser Metal Deposition, Remy Mathenia, Braden Mclain, Todd Sparks, Frank Liou Jul 2024

A Study Of Directionality Effects In Three-Beam Coaxial Titanium Wire-Based Laser Metal Deposition, Remy Mathenia, Braden Mclain, Todd Sparks, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Coaxial wire-based laser metal deposition is a versatile and efficient additive process that can achieve a high deposition rate in the manufacturing of complex structures. In this paper, a three-beam coaxial wire system is studied, with particular attention given to the effects of the deposition direction and laser beam orientation on the resulting bead geometry symmetry. With the three-beam laser delivery, the laser spot pattern is not always symmetric with respect to the deposition direction. Single titanium beads are deposited in different directions and at varying deposition rates, and the bead profile is quantitatively scored for multiple symmetry measures. Through …


Analytical And Fem Models For Thermal Analysis And Residual Stresses Using Wire Arc-Based Welding And Additive Manufacturing Of Sus304, Muhammad Arif Mahmood, Usman Tariq, Mihai Oane, Frank Liou Jul 2024

Analytical And Fem Models For Thermal Analysis And Residual Stresses Using Wire Arc-Based Welding And Additive Manufacturing Of Sus304, Muhammad Arif Mahmood, Usman Tariq, Mihai Oane, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Austenitic stainless steel, also known as SUS304, has a wide industrial application. The resultant residual stresses and deformation due to arc welding play a critical role in an in-service SUS04 part failure. Various experimental studies have been presented to predict residual stresses and part deformation. However, these techniques are expensive and time-consuming owing to the trial-and-error approach, limiting their application to industrial applications. Based on the emergent need, this study introduces two simulation models based on analytical and FEM techniques for thermal distribution and residual stress estimation. The experimentally calibrated models results have been implemented for SUS304 multi-pass arc welding. …


In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah Jul 2024

In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The emergence of 2D materials has significantly expanded the wide range of nanomaterials with diverse applications. Notably, their high conductivity, catalytic efficiency, and hydrophobicity have fueled heightened research interests for water treatment applications. This research aimed to investigate the synthesis and characterization of MXene and reduced graphene oxide (rGO) nanocomposites with silver nanoparticles (Ag) for enhanced catalytic activity in the decomposition of Direct Blue-24 dye. In this study, we employed well-established methods, previously documented in the literature, to prepare two distinct nanocomposites. Novel nanocomposites, namely reduced graphene oxide–silver nanoparticles (rGO–Ag) and MXene–silver nanoparticles (MXene–Ag), were synthesized using the hydrothermal and …