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Atomistic‐Scale Investigation Of Effective Stress Principle Of Saturated Porous Materials By Molecular Dynamics, Chao Zhang, Zhen Liu, Peng Deng Sep 2016

Atomistic‐Scale Investigation Of Effective Stress Principle Of Saturated Porous Materials By Molecular Dynamics, Chao Zhang, Zhen Liu, Peng Deng

Department of Civil, Environmental, and Geospatial Engineering Publications

The effective stress principle is one of the most fundamental concepts in the mechanics of porous materials. Several mathematical expressions have been proposed for this fundamental principle, leading to unsettled debates on the validity and applicability of the principle and its mathematical descriptions. Recent developments in atomistic modeling techniques make it possible to understand multiphase systems at the atomistic scale. In this paper, molecular dynamics simulation is explored as a tool to investigate the stress formulation in porous materials. A molecular dynamics framework, including molecular models of phases, interatomic potentials, initial configuration, and simulation procedure, is presented. Numerical simulations based …


Developing The Greatest Blue Economy: Water Productivity, Fresh Water Depletion, And Virtual Water Trade In The Great Lakes Basin, A. L. Mayer, Stanley Mubako, Benjamin L. Ruddell May 2016

Developing The Greatest Blue Economy: Water Productivity, Fresh Water Depletion, And Virtual Water Trade In The Great Lakes Basin, A. L. Mayer, Stanley Mubako, Benjamin L. Ruddell

Michigan Tech Publications

The Great Lakes basin hosts the world's most abundant surface fresh water reserve. Historically an industrial and natural resource powerhouse, the region has suffered economic stagnation in recent decades. Meanwhile, growing water resource scarcity around the world is creating pressure on water-intensive human activities. This situation creates the potential for the Great Lakes region to sustainably utilize its relative water wealth for economic benefit. We combine economic production and trade datasets with water consumption data and models of surface water depletion in the region. We find that, on average, the current economy does not create significant impacts on surface waters, …


Determination Of Specific Heat Capacity On Composite Shape-Stabilized Phase Change Materials And Asphalt Mixtures By Heat Exchange System, Biao Ma, Xue-Yan Zhou, Jiang Liu, Zhanping You, Kun Wei, Xiao-Feng Huang May 2016

Determination Of Specific Heat Capacity On Composite Shape-Stabilized Phase Change Materials And Asphalt Mixtures By Heat Exchange System, Biao Ma, Xue-Yan Zhou, Jiang Liu, Zhanping You, Kun Wei, Xiao-Feng Huang

Michigan Tech Publications

Previous research has shown that composite shape-stabilized phase change material (CPCM) has a remarkable capacity for thermal storage and stabilization, and it can be directly applied to highway construction without leakage. However, recent studies on temperature changing behaviors of CPCM and asphalt mixture cannot intuitively reflect the thermoregulation mechanism and efficiency of CPCM on asphalt mixture. The objective of this paper is to determine the specific heat capacity of CPCM and asphalt mixtures mixed with CPCM using the heat exchange system and the data acquisition system. Studies have shown that the temperature-rise curve of 5 °C CPCM has an obvious …


Field Tests Of Cement Fly-Ash Steel-Slag Pile Composite Foundation, Bing Zhang, Shuai Cui Apr 2016

Field Tests Of Cement Fly-Ash Steel-Slag Pile Composite Foundation, Bing Zhang, Shuai Cui

Department of Civil, Environmental, and Geospatial Engineering Publications

Steel slag is one of the main waste materials in the steelmaking process. As a result, a tremendous amount of steel slag is produced and deposited into storing yards every year. Recycling of the abandoned steel slag is of great environmental and economic value. This study investigates the usage of steel-slag concrete with fly ash as a kind of composite foundation pile material, which can be applied to multi-pile composition foundations for ground improvement involving different pile types. The micromorphology of the concrete, which uses steel slag as aggregate, is analyzed using scanning electron microscopy (SEM). The bearing characteristics of …


Ethanol Based Foamed Asphalt As Potential Alternative For Low Emission Asphalt Technology, Mohd Rosli Mohd Hasan, Zhanping You Apr 2016

Ethanol Based Foamed Asphalt As Potential Alternative For Low Emission Asphalt Technology, Mohd Rosli Mohd Hasan, Zhanping You

Michigan Tech Publications

Foamed asphalt typically relies on water as a foaming agent because water becomes gaseous at elevated temperatures, generating numerous tiny bubbles in the asphalt and causing spontaneous foaming. In this study, ethanol was used as a potential alternative to water as a foaming agent. Ethanol is expected to be a physical blowing agent in the same manner as water, except it requires less energy to foam due to its 78 °C boiling point. This study compares the performance of water and ethanol as foaming agents through the measurements of rotational viscosity, the reduction in temperature during foaming, and volatile loss. …


Reviews And Syntheses: Ocean Acidification And Its Potential Impacts On Marine Ecosystems, Khan M.G. Mostofa, Cong-Qiang Liu, Weidong Zhai, Marco Minella, David Vione, Kunshan Gao, Daisuke Minakata, Et.Al Jan 2016

Reviews And Syntheses: Ocean Acidification And Its Potential Impacts On Marine Ecosystems, Khan M.G. Mostofa, Cong-Qiang Liu, Weidong Zhai, Marco Minella, David Vione, Kunshan Gao, Daisuke Minakata, Et.Al

Department of Civil, Environmental, and Geospatial Engineering Publications

Ocean acidification, a complex phenomenon that lowers seawater pH, is the net outcome of several contributions. They include the dissolution of increasing atmospheric CO2 that adds up with dissolved inorganic carbon (dissolved CO2, H2CO3, HCO3−, and CO32−) generated upon mineralization of primary producers (PP) and dissolved organic matter (DOM). The aquatic processes leading to inorganic carbon are substantially affected by increased DOM and nutrients via terrestrial runoff, acidic rainfall, increased PP and algal blooms, nitrification, denitrification, sulfate reduction, global warming (GW), and by atmospheric CO2 itself through enhanced photosynthesis. They are consecutively associated with enhanced ocean acidification, hypoxia in acidified …


Use Of Lidar In The Design Of Grassed Waterways: Case Study In Agricultural Management In Oklahoma, Annette Sparks Jan 2016

Use Of Lidar In The Design Of Grassed Waterways: Case Study In Agricultural Management In Oklahoma, Annette Sparks

Dissertations, Master's Theses and Master's Reports

Before the advent of Light Detection and Ranging (LiDAR) technology, farm-level infrastructure for sustainable agriculture was designed using topographic maps. LiDAR is a remote sensing method whereby reflected laser pulses are measured to generate high-resolution 3D images of the terrain. This report compares these two methods in the design of grassed waterways for flood drainage and evaluates how the quantitative difference between the two methods can affect the overall hydrologic design. The benefits of LiDAR are expected to be higher accuracy and precision in design, as well as greater reproducibility or consistency, regardless of the designer. To carry out this …


A Cultural And Technical Study Of Wastewater Treatment Plant Maintenance In A Small Community In Peru, Rebecca C. Midkiff Jan 2016

A Cultural And Technical Study Of Wastewater Treatment Plant Maintenance In A Small Community In Peru, Rebecca C. Midkiff

Dissertations, Master's Theses and Master's Reports

Management of wastewater treatment plants (WWTPs) has been found to be especially challenging in small, rural communities of the developing world. This study examined maintenance of two small WWTPs in Leymebamba and Palmira, Peru through interviews with local authorities, observation of maintenance practices, wastewater measurements, and prediction of effects from maintenance with modeling using a wastewater process simulation software, BioWin. Challenges and motivations related to maintenance were investigated with semi-structured interviews, and maintenance practices were recorded during observations. It was found that outside supervision was a key motivating factor, and the existence of an operator who is supported by the …


Sustainability For Shrinking Cities, Justin L. Herrmann, William D. Shuster, Audrey L. Mayer, Ahjond S. Garmestani Jan 2016

Sustainability For Shrinking Cities, Justin L. Herrmann, William D. Shuster, Audrey L. Mayer, Ahjond S. Garmestani

College of Forest Resources and Environmental Science Publications

Shrinking cities are widespread throughout the world despite the rapidly increasing global urban population. These cities are attempting to transition to sustainable trajectories to improve the health and well-being of urban residents, to build their capacity to adapt to changing conditions and to cope with major events. The dynamics of shrinking cities are different than the dynamics of growing cities, and therefore intentional research and planning around creating sustainable cities is needed for shrinking cities. We propose research that can be applied to shrinking cities by identifying parallel challenges in growing cities and translating urban research and planning that is …


Integrated Computational And Experimental Evaluation Of Electromagnetic Energy-Induced Self-Healing Performance Of Asphalt Composites, Zigeng Wang Jan 2016

Integrated Computational And Experimental Evaluation Of Electromagnetic Energy-Induced Self-Healing Performance Of Asphalt Composites, Zigeng Wang

Dissertations, Master's Theses and Master's Reports

The objective of this doctoral research is to investigate the electromagnetic energy induced self-healing effect of modified asphalt mixture material by developing computational and experimental characterization tools. More than 90% of the pavements in United States are constructed by asphalt mixture. The durability of pavement decreased by distresses has significant impact on maintenance costs. The asphalt mixture has self-healing capability because the asphalt could flow and fill the microcracks if enough external energy can be transmitted to the asphalt mixture system. However, the self-healing capability of asphalt is limited based on the climatic condition and traffic volume. Therefore, it is …


Probability-Based Hurricane Resilience Evaluation And Retrofitting For Residential Community, Yadong Dong Jan 2016

Probability-Based Hurricane Resilience Evaluation And Retrofitting For Residential Community, Yadong Dong

Dissertations, Master's Theses and Master's Reports

Wood residential construction is vulnerable to hurricanes, as evident in recent hurricane events. Many studies indicated that the changing climate may very likely alter hurricane patterns, which could lead to more severe hurricane damage to the wood residential construction that accounts for 90% of the residence in the USA. On the other hand, deterioration of material increases the chance of structural failure by reducing the structural capacity (e.g., corrosion of fasteners in roof panel could significantly reduce the withdrawal capacity of the roofing structure during hurricane events).

Currently, most hurricane damage estimations only focus on direct loss (e.g., structural loss). …


The Effect Of Community Connectivity On Water And Sanitation Systems In Rural Panama, M.C. Moritz Jan 2016

The Effect Of Community Connectivity On Water And Sanitation Systems In Rural Panama, M.C. Moritz

Dissertations, Master's Theses and Master's Reports

The world has yet to realize universal access to water and sanitation. Various academic and professional fields provide frameworks for understanding water and sanitation access, but none directly consider the impact of community connectivity. Community connectivity refers to the infrastructures linking rural communities with urban centers. These infrastructures fall under the broad categories of transportation, energy, and telecommunication. This paper examines 23 rural Panamanian communities and compares connectivity measures with the functionality of the communities’ rural water and sanitation systems (RWSS). Community connectivity was evaluated with the Community Connectivity Analysis Tool (CCAT), while the water and sanitation systems were evaluated …


Designing A Permeable Reactive Barrier For The Remediation Of Copper Contaminated Groundwater., Christopher Walkons Jan 2016

Designing A Permeable Reactive Barrier For The Remediation Of Copper Contaminated Groundwater., Christopher Walkons

Dissertations, Master's Theses and Master's Reports

This project details the design of a sorption based pilot-scale permeable reactive barrier (PRB) for the removal of copper from groundwater. The reactive material for the barrier is the residual of coagulants used in drinking water treatment operations. Physical and chemical properties of these water treatment residuals (WTR) have been studied to optimize PRB design. Batch reactor tests have shown that equilibrium sorption of copper can be fit to a Langmuir type isotherm. Kinetic and column experiments have been conducted to understand the significance of chemical and physical mass transfer limitations. A leaching test indicated the concentrations of hazardous elements …


A Sustainability-Based Project Selection Algorithm: Socio-Technical-Economic Project Selection (Steps) Algorithm, Bharathi Bhattu Jan 2016

A Sustainability-Based Project Selection Algorithm: Socio-Technical-Economic Project Selection (Steps) Algorithm, Bharathi Bhattu

Dissertations, Master's Theses and Master's Reports

Multi-dimensional aspects play a vital role in the task of project-decision making. Environmental effects are to be considered in addition to other technical and non-technical aspects in order to avoid undue environmental damage. This current work introduces a new decision-making algorithm (Socio-Technical-Economic Project Selection or STEPS) that is demonstrated with the use of RCA (recycled concrete aggregate) as riprap for slope stabilization and erosion control which leaches chemical arsenic when in contact with water. Arsenic has long been recognized for its lethal properties. The main intention of introducing this new algorithm is to use sustainability concepts of social, technical, and …


Methodology For Analyzing Epoxy-Cnt Phononic Crystals For Wave Attenuation And Guiding, Madhu Kolati Jan 2016

Methodology For Analyzing Epoxy-Cnt Phononic Crystals For Wave Attenuation And Guiding, Madhu Kolati

Dissertations, Master's Theses and Master's Reports

Phononic crystals (PhnCs) control, direct and manipulate sound waves to achieve wave guiding and attenuation. This dissertation presents methodology for analyzing nanotube materials based phononic crystals to achieve control over sound, vibration and stress mitigation. Much of the analytical work presented is in identifying frequency band gaps in which sound or vibration cannot propagate through these PhnCs. Wave attenuation and mitigation analysis is demonstrated using finite element simulation. Engineering principles from current research areas of solid mechanics, solid-state physics, elasto-dynamics, mechanical vibrations and acoustics are employed for the methodology. A considerable effort is put to show that these PhnCs can …


Evaluating The Anaerobic Codigestion Potential Of Stillage And Dairy Manure In A Tubular Digester, Brad J. Weiss Jan 2016

Evaluating The Anaerobic Codigestion Potential Of Stillage And Dairy Manure In A Tubular Digester, Brad J. Weiss

Dissertations, Master's Theses and Master's Reports

Evaluations of the anaerobic treatment of sugarcane stillage and dairy manure in a low cost tubular digester were performed in small scale batch experiments and using mathematical simulations. A local sensitivity analysis of the model was performed, and key input parameters were adjusted until the predicted COD removal was consistent with data obtained using two full-scale digesters. Simulations were performed to evaluate COD removal and biogas production for nine different mixtures of stillage and manure at four different temperatures ranging from 15˚C to 30˚C. Digestion of stillage alone was not effective, but when codigested with 20% or more manure, COD …


Dust Susceptibility At Mine Tailings Impoundments: Thermal Remote Sensing For Dust Susceptibility Characterization And Biological Soil Crusts For Dust Susceptibility Reduction, Bonnie Zwissler Jan 2016

Dust Susceptibility At Mine Tailings Impoundments: Thermal Remote Sensing For Dust Susceptibility Characterization And Biological Soil Crusts For Dust Susceptibility Reduction, Bonnie Zwissler

Dissertations, Master's Theses and Master's Reports

Mining operations produce massive volumes of mine tailings, which are deposited as slurry into permanent tailings impoundments. An important and heavily regulated environmental hazard associated with mine tailings impoundments is fugitive dust emissions. Wind erosion of mine tailings impoundments and the resulting dusting events, especially those caused by cold weather dusting, remain an on-going challenge for the mining industry. The overall goal of this research was to develop and evaluate effective, economical, and sustainable solutions to two major issues facing mine tailings impoundments with regards to dusting: (1) dust monitoring/detection and (2) dust reduction/prevention. Specifically, the research studied iron mine …


A Characterization Of The Water Quality Conditions And Pollutant Loads In Surface Waters Near The Northeast Ohio Regional Sewer District’S Combined Sewer System In Cleveland, Ohio, Nathan Zgnilec Jan 2016

A Characterization Of The Water Quality Conditions And Pollutant Loads In Surface Waters Near The Northeast Ohio Regional Sewer District’S Combined Sewer System In Cleveland, Ohio, Nathan Zgnilec

Dissertations, Master's Theses and Master's Reports

The Northeast Ohio Regional Sewer District (NEORSD, Cleveland, OH) serves over one million citizens through the operation of three waste water treatment plants. NEORSD provides this service through combined and separated sewer systems, which, during rainfall events, are known to deliver large volumes of untreated wastewater containing high concentrations of Escherichia coli (E.coli), ammonia nitrogen, and phosphorus. NEORSD is currently investing $3 billion over the next 25 years to mitigate its combined sewer overflows and plans to allocate additional funds to improve remaining pollutant sources related to its system, e.g. separated sewers. A suite of PC-SWMM pollutant loading models have …


Evaluating Groundwater Recharge In The Saloum Region Of Senegal, Alexander Wohlgemuth Jan 2016

Evaluating Groundwater Recharge In The Saloum Region Of Senegal, Alexander Wohlgemuth

Dissertations, Master's Theses and Master's Reports

Approximately 1.2 billion people in the world live in an area facing physical, or absolute, water scarcity (defined as access to less than 1,000 cubic meters of water). This number is projected to increase to 1.8 billion by the year 2025. Thirty-eight percent of the world’s population lives in arid, semi-arid or dry subhumid regions, which translates to a high dependence on the 30% of the world’s freshwater present in the ground. Further, the rate of water use is increasing rapidly – between two and two and a half times that of population growth, over the last century.

In regions …


Polychlorinated Biphenyl Compound And Metal Contamination And Remediation In Torch Lake, Houghton County, Mi, Ankita Mandelia Jan 2016

Polychlorinated Biphenyl Compound And Metal Contamination And Remediation In Torch Lake, Houghton County, Mi, Ankita Mandelia

Dissertations, Master's Theses and Master's Reports

Torch Lake was subject to approximately 100 years of industrial pollution due to the dumping of waste associated with copper mining in the Keweenaw Peninsula, which lasted from approximately the 1860s through the 1960s. It is well-known that this waste included copper-containing mine tailings. What was less understood are the impacts of polychlorinated biphenyls (PCBs) and heavy metals besides copper on the lake system.

The objectives of this thesis are to summarize the status of contamination and remediation activities in Torch Lake and to estimate the magnitude of potential sources of PCBs to Torch Lake. First, a brief overview of …


Effect Of Fiber Orientation On Dynamic Compressive Properties Of An Ultra-High Performance Concrete, Andrew B. Groeneveld Jan 2016

Effect Of Fiber Orientation On Dynamic Compressive Properties Of An Ultra-High Performance Concrete, Andrew B. Groeneveld

Dissertations, Master's Theses and Master's Reports

Casting structural elements with ultra-high performance concrete (UHPC) tends to create preferential fiber alignment, which affects the strength and must be accounted for in design. Fiber orientation effects in tension have been studied extensively, but less work has been performed for compression. This work characterizes the fiber orientation occurring in a typical UHPC beam and how that orientation affects compressive behavior at high strain rates. Specimens (36 total) were cored from the beam and their fiber orientations were non-destructively evaluated using x-ray computed tomography (CT). Fibers showed flow-induced alignment along the length of the beam, with orientation angles in the …


Pilot-Scale Study Of Low-Tech Methods Of Sustainable Class A Biosolids Production: A Trial Run, Rebecca L. Green Jan 2016

Pilot-Scale Study Of Low-Tech Methods Of Sustainable Class A Biosolids Production: A Trial Run, Rebecca L. Green

Dissertations, Master's Theses and Master's Reports

Water resource recovery facilities can improve sustainability by producing Class A biosolids. However, many conventional methods for achieving Class A biosolids are expensive, with high maintenance and energy costs. However, low-cost, low-tech (LCLT) treatment methods are also available. The overall goal of the larger project of which this study was a part is to develop a rational and universal approach for design of LCLT processes. To achieve this goal, pilot-scale studies of LCLT processes will be performed. The goal of this portion of the project was to perform a trial run pilot-scale study. During the trial run, the pilot-scale biosolids …


Reactivity Of Hydroxyl Radical: Mechanistic Insight Into The Reactivity With Dissolved Organic Matter, Mallika Khare Jan 2016

Reactivity Of Hydroxyl Radical: Mechanistic Insight Into The Reactivity With Dissolved Organic Matter, Mallika Khare

Dissertations, Master's Theses and Master's Reports

Advanced Oxidation Processes (AOPs) that produce highly reactive hydroxyl radicals (HO•) are attractive and promising water and wastewater treatment technologies because HO• can destroy a variety of organic compounds. However, background dissolved organic matter (DOM) significantly reduces the performance of AOPs by scavenging HO•. The conventional experimental approach to identifying ‘average’ reactivity limits our mechanistic understanding of the reaction of HO• with complex mixture of surrogate DOM. This is the first study to use quantum mechanical methods to understand the elementary reactions of HO• with a model monomer of DOM. “Temple Northeastern Birmingham model” (TNB). The theoretically calculated aqueous-phase free …


Temporal Trends And Spatial Variabilities Of Pcb Concentrations In Lake Trout From Lake Superior From 1995 To 2013, Hongyi Lin Jan 2016

Temporal Trends And Spatial Variabilities Of Pcb Concentrations In Lake Trout From Lake Superior From 1995 To 2013, Hongyi Lin

Dissertations, Master's Theses and Master's Reports

It has been frequently reported that concentrations of PCBs in the Great Lakes fish have declined dramatically since their ban on production and use in 1979 in the United States, although some studies suggested that recent rates of decline are leveling off. In order to examine the temporal trends and spatial variabilities of PCB concentrations in lake trout (Salvelinus namaycush) from Lake Superior during the past two decades, statistical analyses were performed on fish sample data collected by two national agencies (U.S. EPA, Environment and Climate Change Canada) and three state agencies (Michigan Department of Environmental Quality, Minnesota …


Risk-Based Assessment And Strengthening Of Electric Power Systems Subjected To Natural Hazards, Abdullahi Salman Jan 2016

Risk-Based Assessment And Strengthening Of Electric Power Systems Subjected To Natural Hazards, Abdullahi Salman

Dissertations, Master's Theses and Master's Reports

Modern economic and social activities are dependent on a complex network of infrastructure systems that are highly interdependent. Electric power systems form the backbone of such complex network as most civil infrastructure systems cannot function properly without reliable power supply. Electric power systems are vulnerable to extensive damage due to natural hazards, as evident in recent hazard events. Hurricanes, earthquakes, floods, tornados and other natural hazards have caused billions of dollars in direct losses due to damage to power systems and indirect losses due to power outages, as well as social disruption. There is, therefore, a need for a comprehensive …


Assessing The Impacts Of Climate Change On The Surface Temperature Of Inland Lakes In Michigan, Kaitlin Reinl Jan 2016

Assessing The Impacts Of Climate Change On The Surface Temperature Of Inland Lakes In Michigan, Kaitlin Reinl

Dissertations, Master's Theses and Master's Reports

The aim of this study was to validate and apply a lake model for predicting the susceptibility of small inland lakes in Michigan to changes in thermal regime and increased cyanobacteria growth as a result of future climate conditions. The Freshwater Lake Model was selected, tested for sensitivity to various inputs, and validated through comparison to observed conditions. The sensitivity analysis showed that the lake model was most sensitive to solar radiation, air temperature, and air humidity. Comparison of predicted climate data with observed conditions revealed highly variable climate model error. The lake model validation was conducted using 10 lakes …


Property Analysis Of The Asphalt Materials Using Molecular Dynamics (Md) Method, Hui Yao Jan 2016

Property Analysis Of The Asphalt Materials Using Molecular Dynamics (Md) Method, Hui Yao

Dissertations, Master's Theses and Master's Reports

The main objectives of this dissertation are to build the Molecular Dynamics (MD) model for the asphalt binders with three components, asphaltenes, aromatics and saturates, and analyze the properties of the asphalt models to discover the interactions and mechanisms of asphalt-aggregate and asphalt-modifier. The contributions of this dissertation are summarized as follows: (1) the Amber Cornell Extension Force Field (ACEFF) was assigned to each component, and most of the parameters of the force field were obtained from the General Amber Force Field (GAFF). Electrostatic Potential (ESP) charges were assigned to each atom with the NWChem calculation; (2) the modified asphalt …


Modeling Impacts Of Combined Sewer Overflows In Swmm In Cleveland, Ohio, Zoe A. Miller Jan 2016

Modeling Impacts Of Combined Sewer Overflows In Swmm In Cleveland, Ohio, Zoe A. Miller

Dissertations, Master's Theses and Master's Reports

Despite its legacy of pollution, the City of Cleveland, Ohio, has historically been at the forefront of water quality management. Today, the Northeast Ohio Regional Sewer District (NEORSD), which serves the Greater Cleveland area, is following a consent decree with the State of Ohio to minimize combined sewer overflows (CSOs), along with implementing an integrated Clean Water Act planning study to prioritize infrastructure improvements with a broader view of water quality objectives. This report summarizes an urban watershed modeling effort to support the integrated planning (IP) process. Specifically, the development, calibration, and validation of the EPA Stormwater Management Model (SWMM) …