Synergetic Effect Of Viscosity Modifying Admixtures And Polycarboxylate Ether Superplasticizer On Key Characteristics Of Thixotropic Uhpc For Bonded Bridge Deck Overlay Rehabilitation, 2024 Missouri University of Science and Technology
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 …
Laboratory Evaluation And Field Demonstration Of Cold In-Place Recycling Asphalt Mixture In Michigan Low-Volume Road, 2024 Michigan Technological University
Laboratory Evaluation And Field Demonstration Of Cold In-Place Recycling Asphalt Mixture In Michigan Low-Volume Road, Dongzhao Jin, Lei Yin, Lance Malburg, Zhanping You
Michigan Tech Publications, Part 2
Cold-in place recycling (CIR) is a promising technology for the rehabilitation of asphalt pavements. However, the CIR asphalt pavement constructed in the field often has high air voids due to the presence of moisture during construction, and the moisture susceptibility of the pavement is crucial in determining its service life. Therefore, the objective of this research was to assess the laboratory performance of CIR asphalt mixes under freeze-thaw conditions (The mix prior to being subjected to freezing and thawing is labeled as "dry condition", while the mix that was placed in a refrigerator at –18 °C for 16 h and …
Understanding The Impact Of Microplastic Contamination On Soil Quality And Eco-Toxicological Risks In Horticulture: A Comprehensive Review, 2024 Edith Cowan University
Understanding The Impact Of Microplastic Contamination On Soil Quality And Eco-Toxicological Risks In Horticulture: A Comprehensive Review, N. P. Gayathri, Geena Prasad, Vaishna Prabhakaran, Vishnu Priya
Research outputs 2022 to 2026
The horticulture sector, essential for global food production, confronts significant challenges with prevalent pollutants, mainly microplastics. The presence of microplastics in the food chain has induced physiological stress and a multifactorial food safety concern. The complexity of the problem, arising from intricate interactions among microplastics, organisms, and ecosystems, poses a substantial challenge to food safety, necessitating an immediate strategic perspective due to the associated risks to human health and eco-toxicology. Significant knowledge gaps persist regarding their impact on terrestrial ecosystems, especially in horticulture. This study addresses the urgent need to comprehend the implications of microplastics on soil health, eco-toxicological risks, …
Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, 2024 Utah State University
Tracking Perfluoroalkyl Substances From Wastewater Influent To Its Accumulation In Vegetables And Forage Grass, Simon Kozik
All Graduate Theses and Dissertations, Fall 2023 to Present
Per and poly-fluorinated alkyl substances (PFAS) are a class of chemicals that are persistent in the environment. PFAS was found in wastewater, which can be used after wastewater treatment for irrigation water, and in the biosolids that can be mixed with soils to provide nutrients and generally improve soil quality. This study found when wastewater was used it increases the level of PFAS in vegetables and forage grass. PFAS concentrations were tracked from the influent of the wastewater treatment plant to the effluent, to the irrigation water, to the soil, and finally into the vegetable and forage grass grown on …
Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, 2024 University of New Mexico
Physical And Stochiometric Controls On Nutrient Uptake And Ecosystem Respiration In Contrasting Sites, Jancoba K. Dorley
Civil Engineering ETDs
Meteorological, hydrological, and biogeochemical processes naturally control stream ecosystems. These processes define the frequency and distribution of precipitation and the supply and demand of solutes and particles to support aquatic food chains through space and time. Studies have also found that stream ecosystems are also controlled by anthropogenic activities, which occur on a much shorter timescale. These anthropogenic activities affect stream ecosystems' structure and function from local to planetary changes to the environment. It is essential for scientists and engineers to understand the relationships between naturally occurring processes and those created by human activities for a better interpretation of stream …
A Review Of Whipple Shield Ballistic Limit Equations, 2024 Missouri University of Science and Technology
A Review Of Whipple Shield Ballistic Limit Equations, S. Ryan, W. (William) P. Schonberg
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Ballistic limit equations (BLEs) are semi-analytical expressions used to predict the risk posed by micrometeoroid and orbital debris (MMOD) impacts on a spacecraft. A foundational BLE, known as the new non-optimum (NNO) equation was published by Eric Christiansen of NASA Johnson Space Center in 1990 for application on Whipple shields – two-plate configurations consisting of a thin sacrificial plate located at some standoff in front of the spacecraft pressure hull or structural wall. Today, BLEs for almost all multi-plate spacecraft structures, e.g., honeycomb sandwich panels, monolithic structures with thermal insulation blankets, etc., are based on the NNO Whipple BLE. We …
Modeling Inflation Transmission Among Different Construction Materials, 2024 Missouri University of Science and Technology
Modeling Inflation Transmission Among Different Construction Materials, Mohamad Abdul Nabi, Islam H. El-Adaway, Rayan H. Assaad
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Cost estimating in the construction industry is challenging due to the high uncertainty associated with the supply chain, especially after the COVID-19 pandemic. Some research studies have addressed such problems by developing models that predict material cost. In fact, all material can be interconnected and interrelated with lead-lag relationships such that any inflation in one material's price can be associated with inflation in other materials' prices, referred to as transmission of inflation. Despite the latter, none of the existing studies have investigated inflation transmission among all construction materials. This paper fills this knowledge gap. The authors used a multistep research …
Microplastics Fouling Mitigation In Forward Osmosis Membranes By The Molecular Assembly Of Sulfobetaine Zwitterion, 2024 Edith Cowan University
Microplastics Fouling Mitigation In Forward Osmosis Membranes By The Molecular Assembly Of Sulfobetaine Zwitterion, Javad Farahbakhsh, Mitra Golgoli, Mehdi Khiadani, Amir Razmjou, Masoumeh Zargar
Research outputs 2022 to 2026
Forward osmosis (FO) membranes have potential for the efficient water and wastewater treatment applications. However, their development has faced significant challenges due to their fouling propensity. In this study, FO membranes modified with sulfobetaine zwitterions (i.e., [2-(Methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide) were fabricated and used for the first time to address microplastic (MP) fouling issue. Water flux, reverse salt flux (RSF), fouling, and flux recovery were evaluated for the membranes loaded with different quantities of the zwitterions ranging from 0.25 % to 2 %. The developed membranes were tested over 49 h with feed solutions containing polyethylene MPs and bovine serum albumin …
Performance Enhancement Of A Solar-Driven Dcmd System Using An Air-Cooled Condenser And Oil: Experimental And Machine Learning Investigations, 2024 Edith Cowan University
Performance Enhancement Of A Solar-Driven Dcmd System Using An Air-Cooled Condenser And Oil: Experimental And Machine Learning Investigations, Pooria Behnam, Abdellah Shafieian, Masoumeh Zargar, Mehdi Khiadani
Research outputs 2022 to 2026
Solar-driven direct contact membrane distillation systems (DCMD) are disadvantaged by low freshwater productivity and low gain-output-ratio (GOR). Consequently, this study aims to achieve two primary objectives: i) improving the solar DCMD performance, and ii) harnessing machine learning models for precise and straightforward modeling of the solar DCMD system. To achieve these goals, a novel solar DCMD system powered with oil-filled heat pipe evacuated tube collectors (HP-ETCs) and equipped with an air-cooled condenser was used for the first time. The system was evaluated under eight different scenarios covering both its energy and economic performances. The performance prediction of three different machine …
Risk–Reward Share Allocation Under Different Integrated Project Delivery Relational Structures: A Monte-Carlo Simulation And Cooperative Game Theoretic Solutions Approach, 2024 Missouri University of Science and Technology
Risk–Reward Share Allocation Under Different Integrated Project Delivery Relational Structures: A Monte-Carlo Simulation And Cooperative Game Theoretic Solutions Approach, Radwa Eissa, Mohamad Abdul Nabi, Islam H. El-Adaway
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Sharing of risks and rewards is considered to be one of the key benefits and principles of integrated project delivery (IPD). Despite its importance, risk–reward strategies are not implemented widely in IPD construction projects due to the lack of a well-defined basis for establishing adequate allocation plans. This paper fills this knowledge gap. This research followed a multistep methodology. First, the authors calculated the risk control valuations of all potential combinations of coalitions for IPD stakeholders. This was performed using interrelated steps of risk identification and quantification, risk assignment based on associated contractual analysis, establishment of a coordination network, and …
Comprehensive Understanding Of Factors Impacting Competitive Construction Bidding, 2024 Missouri University of Science and Technology
Comprehensive Understanding Of Factors Impacting Competitive Construction Bidding, Muaz O. Ahmed, Islam H. El-Adaway, Aubrie Caldwell
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Construction competitive bidding has been studied by many researchers; however, their focus was mainly on certain bidding aspects. Thus, despite their value, existing bidding models have limited applicability for various reasons including the non-inclusion of some real-life factors that impact bidding-related decisions. As such, there is a need for identifying a comprehensive list of bidding factors that impact construction bidding-related decisions, studying their associations, and identifying understudied factors to direct future research efforts. This paper fills this knowledge gap. First, the authors conducted a systematic selection of 124 construction bidding-related articles published within the past 40 years. Second, the authors …
Bioaerosol Size As A Potential Determinant Of Airborne E. Coli Viability Under Ultraviolet Germicidal Irradiation And Ozone Disinfection, 2024 Missouri University of Science and Technology
Bioaerosol Size As A Potential Determinant Of Airborne E. Coli Viability Under Ultraviolet Germicidal Irradiation And Ozone Disinfection, Weixing Hao, Yue-Wern Huang, Yang Wang
Biological Sciences Faculty Research & Creative Works
Ultraviolet germicidal irradiation (UVGI) and ozone disinfection are crucial methods for mitigating the airborne transmission of pathogenic microorganisms in high-risk settings, particularly with the emergence of respiratory viral pathogens such as SARS-CoV-2 and avian influenza viruses. This study quantitatively investigates the influence of UVGI and ozone on the viability of E. coli in bioaerosols, with a particular focus on how E. coli viability depends on the size of the bioaerosols, a critical factor that determines deposition patterns within the human respiratory system and the evolution of bioaerosols in indoor environments. This study used a controlled small-scale laboratory chamber where E. …
Assessment Of Walls With Phase Change Materials Through Synergistic And Performance Measures Using Experimental And Simulated Test Houses, 2024 Olivet Nazarene University
Assessment Of Walls With Phase Change Materials Through Synergistic And Performance Measures Using Experimental And Simulated Test Houses, Cory J. Enfield
ELAIA
Current research on living and working spaces continues to strive to identify the most energy-efficient methods for heating and cooling, and many novel technologies have emerged from the research. One of the most promising, and the topic of this quantitative analysis, is the retrofitting of phase change materials (PCMs) into the walls of structures. Research has shown positive results, such as a reduced transfer of heat through walls, when PCMs are retrofitted into wall construction. The present research takes previously gathered data from test houses, built with typical North American framing, and simulates an additional fourteen test houses from the …
Modeling And Understanding Dispute Causation In The Us Public-Private Partnership Projects, 2024 Missouri University of Science and Technology
Modeling And Understanding Dispute Causation In The Us Public-Private Partnership Projects, Mohamad Abdul Nabi, Rayan H. Assaad, Islam H. El-Adaway
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The partnership between the public and private sectors has led to a new and innovative way of delivering infrastructure projects that is referred to as public-private partnership (PPP). There are various benefits associated with PPP delivery methods including risk sharing, access to private funding, innovation, and flexibility, among others. Despite the proved benefits, contract conflicts and disputes are very common in PPP projects. While previous research studies examined the risks and the potential causes of conflicts in PPP projects, little-to-no research efforts were directed to study and model the interconnectivities between the different causes of conflicts in PPP agreements. To …
Methodology To Design Eco-Friendly Fiber-Reinforced Concrete For 3d Printing, 2024 Missouri University of Science and Technology
Methodology To Design Eco-Friendly Fiber-Reinforced Concrete For 3d Printing, Haodao Li, Alfred Addai-Nimoh, Eric Kreiger, Kamal H. Khayat
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Greater use of locally available supplementary cementitious materials (SCM) to reduce cement content and addition of fiber reinforcement can enhance the performance of 3D printing (3DP) technology in construction. In this study, three classes of eco-friendly 3D printable fiber-reinforced mixtures were targeted, namely ultra-high-performance concrete (UHPC), high-performance concrete (HPC), and conventional concrete (CC). A step-by-step methodology was proposed to maximize the substitution rate of cement with SCM and limestone filler and optimize fiber volume for the successful development of 3D printable fiber-reinforced materials. Binder combinations were initially investigated on the paste level to determine the packing density and robustness. Selected …
Wave Overtopping Layer Thickness On The Crest Of Rubble Mound Seawalls, 2024 Edith Cowan University
Wave Overtopping Layer Thickness On The Crest Of Rubble Mound Seawalls, Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. Van Gent
Research outputs 2022 to 2026
During storms, ensuring the protection of people, vehicles and infrastructure on the crest of coastal structures from wave overtopping hazards is crucial. The thickness of the wave overtopping layer is a key variable used for assessing safety and maintaining a secure design. Traditionally, this parameter is associated with the height difference between the fictitious wave run-up level exceeded by 2% of waves and the crest freeboard of coastal structures. This study aims to investigate the wave overtopping layer thickness on the crest of rubble mound seawalls. To achieve this, a series of 125 small-scale 2D physical model tests were conducted …
Distributed Solar Generation: Current Knowledge And Future Trends, 2024 Missouri University of Science and Technology
Distributed Solar Generation: Current Knowledge And Future Trends, Gasser G. Ali, Islam H. El-Adaway
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Distributed solar generation (DSG) has been growing over the previous years because of its numerous advantages of being sustainable, flexible, reliable, and increasingly affordable. DSG is a broad and multidisciplinary research field because it relates to various fields in engineering, social sciences, economics, public policy, and others. Developing a holistic understanding of the state of research related to DSG can be difficult. Motivated to provide that understanding, the goal of this paper is to explore current and emerging multidisciplinary research trends associated with DSG. To achieve that, (1) a large data set of approximately 66,000 publications was collected; (2) the …
Circular Economy Policies For Decarbonization Of Us Commercial Building Stocks: Data Integration And System Dynamics Coflow Modeling Approach, 2024 Missouri University of Science and Technology
Circular Economy Policies For Decarbonization Of Us Commercial Building Stocks: Data Integration And System Dynamics Coflow Modeling Approach, Radwa Eissa, Islam H. El-Adaway
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Despite the recognition of the built environment as a sector with high potential for reducing embodied emissions, there is a lack of national-level data on embodied carbon emissions attributed to the US commercial building stocks. Hence, there is a need to benchmark the current state of embodied emissions attributed to the commercial built environment and the impact of circular economy (CE) policies for their decarbonization to facilitate well-informed decision-making. This paper fills this knowledge gap through providing policy makers with a framework that estimates the current and future projections of embodied carbon emissions attributable to the US commercial building stocks …
Lateral Load Response Of Semi-Interlocking Mortarless Masonry-Infilled Frames, 2024 Edith Cowan University
Lateral Load Response Of Semi-Interlocking Mortarless Masonry-Infilled Frames, Sonam Dorji, Hossein Derakhshan, David P. Thambiratnam, Alireza Mohyeddin
Research outputs 2022 to 2026
Structural frames infilled with masonry material called masonry-infilled frames (MIFs) are common types of constructions around the world. These structures generally have mortared masonry as infill material which made the buildings stiff during past earthquakes and generated additional torsional forces. With a view to improve the seismic performance of MIFs this paper presents the results of a numerical simulation study on the behaviour of previously-tested MIFs with semi-interlocking masonry (SIM) material. In a simplified micro-modelling approach, the concrete and masonry materials are simulated using Concrete Damaged Plasticity technique and the joints are considered as zero-thickness cohesive interfaces modelled using traction-separation …
Implementation Of Fluid Viscous Damper For 2023 Eeri Seismic Design Competition, 2024 California Polytechnic State University, San Luis Obispo
Implementation Of Fluid Viscous Damper For 2023 Eeri Seismic Design Competition, Dalton J. Muck, Payton S. Mcgee, Payton R. Filippin, Tynan Castro
Architectural Engineering
The authors of this report were a part of the 2023 Earthquake Engineering Research Institute (EERI) student chapter for California Polytechnic State University, San Luis Obispo (Cal Poly). With thirteen other team members, they traveled to San Francisco, CA to compete in the Seismic Design Competition (SDC) hosted by EERI. The team was tasked with preparing a written proposal, design and computer analysis of the structural system, construction of two physical models, as well as creation of a poster and a presentation for a proposed mid-rise building located in the competition host city. The goal of the design of Cal …