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Experimental Study Of Low Cycle Fatigue Properties For Epoxy Resins With Dibutyl Phthalate (Dbp), Zhi Wang, Jiajia Zhou, Lianjian Song, Long Li Dec 2018

Experimental Study Of Low Cycle Fatigue Properties For Epoxy Resins With Dibutyl Phthalate (Dbp), Zhi Wang, Jiajia Zhou, Lianjian Song, Long Li

Department of Civil, Environmental, and Geospatial Engineering Publications

In order to improve the toughness of traditional epoxy resin, dibutyl phthalate (DBP) was introduced into the epoxy resin. The static mechanical performance of plasticized and unplasticized epoxy resin was evaluated. The test results showed that the DBP modified epoxy resin can obtain a higher toughness than conventional epoxy resin, but the elastic modulus and the tensile strength were slightly reduced. The low cycle fatigue test results indicated that the stress ratio and the stress level were two critical factors of fatigue life, which was increased with the growth of stress ratio. It was also found that the fatigue life …


Dynamic Response Analysis Of Rutting Resistance Performance Of High Modulus Asphalt Concrete Pavement, Chundi Si, Enli Chen, Zhanping You, Riulan Tian, Ran Zhang, Junfeng Gao Dec 2018

Dynamic Response Analysis Of Rutting Resistance Performance Of High Modulus Asphalt Concrete Pavement, Chundi Si, Enli Chen, Zhanping You, Riulan Tian, Ran Zhang, Junfeng Gao

Department of Civil, Environmental, and Geospatial Engineering Publications

In order to systematically study the rutting resistance performance of High-Modulus Asphalt Concrete (HMAC) pavements, a finite element method model of HMAC pavement was established using ABAQUS software. Based on the viscoelasticity theory of asphalt, the stress and deformation distribution characteristics of HMAC pavement were studied and compared to conventional asphalt pavement under moving loads. Then, the pavement temperature field model was established to study the temperature variation and the thermal stress in HMAC pavement. Finally, under the condition of continuous temperature variation, the creep behavior and permanent deformation of HMAC pavement were investigated. The results showed that under the …


Effective Exploitation Potential Of Shale Gas From Lower Cambrian Niutitang Formation, Northwestern Hunan, China, Han Cao, Tianyi Wang, Ting Bao, Pinghe Sun, Zheng Zhang, Jingjing Wu Dec 2018

Effective Exploitation Potential Of Shale Gas From Lower Cambrian Niutitang Formation, Northwestern Hunan, China, Han Cao, Tianyi Wang, Ting Bao, Pinghe Sun, Zheng Zhang, Jingjing Wu

Michigan Tech Publications

The marine shale in the Lower Cambrian Niutitang Formation is the dominant shale-gas reservoir in northwestern Hunan, which accounts for more than 70% of unconventional energy in Hunan province. Accurately evaluating the shale-gas exploitation potential is a key to determining whether commercial exploitation standards can be met. In the literature, most existing studies have focused on evaluating the shale-gas exploitation potential based on either accumulation conditions or the shale fracability, which will lead to a gap between the real production and proven gas reserves due to the characteristics of the shale’s low permeability and low porosity. Therefore, further studies are …


Nondestructive Assessment Of Wood Members In A Viewing Tower In Potawatomi State Park, Door County, Wisconsin, Us, Robert Ross, Xiping Wang, C. Adam Senalik Dec 2018

Nondestructive Assessment Of Wood Members In A Viewing Tower In Potawatomi State Park, Door County, Wisconsin, Us, Robert Ross, Xiping Wang, C. Adam Senalik

College of Forest Resources and Environmental Science Publications

The State of Wisconsin’s Department of Natural Resources is responsible for operating one of the largest state park systems in the United States. Potawatomi State Park, located on the Door County peninsula, consists of about 1,200 acres of flat to gently rolling upland terrain bordered by steep slopes and rugged limestone cliffs along Lake Michigan’s shoreline. A 75-ft observation tower sits atop a 150-ft bluff overlooking Lake Michigan. The USDA Forest Service, Forest Products Laboratory, was asked to conduct an assessment of the main support timbers of the tower. This report summarizes the results obtained from the inspection and assessment. …


Rheological Performance Of Bio-Char Modified Asphalt With Different Particle Sizes, Ran Zhang, Qingli Dai, Zhanping You, Hainian Wang, Chao Peng Sep 2018

Rheological Performance Of Bio-Char Modified Asphalt With Different Particle Sizes, Ran Zhang, Qingli Dai, Zhanping You, Hainian Wang, Chao Peng

Michigan Tech Publications

To improve the performance of petroleum asphalt, bio-char was used as a modifier for a petroleum asphalt binder, in this study. The rheological properties of bio-char modified asphalt binders were compared with different particle sizes and contents, with one control and one flake graphite modified asphalt binder. Specifically, the bio-char modifiers with two particle sizes (ranging from 75 μm–150 μm and less than 75 μm) and three contents of 2%, 4%, and 8% were added into the asphalt binder. A flake graphite powder with particle sizes less than 75 μm was used as a comparison modifier. The Scanning Electron Microscopy …


Standardization Of Fatigue Characteristics Of Cement-Treated Aggregate Base Materials Under Different Stress States, Jiawei Xie, Limin Tang, Songtao Lv, Naitian Zhang, Tuo Huang, Hongfu Liu Sep 2018

Standardization Of Fatigue Characteristics Of Cement-Treated Aggregate Base Materials Under Different Stress States, Jiawei Xie, Limin Tang, Songtao Lv, Naitian Zhang, Tuo Huang, Hongfu Liu

Michigan Tech Publications

In this study, to decrease the evaluation uncertainty of the fatigue characteristics of cement-treated aggregate base materials under different test conditions, unconfined compressive, indirect tensile, flexural tensile strength tests and fatigue tests of these base materials with different cement content and at different curing times were carried out. The Weibull distribution was employed to analyze fatigue test results. The standardization model of fatigue characteristics for cement-treated aggregate base materials under different stress states was established. Based on the interval analysis theory, the fatigue characteristic model under different stress states was established using interval parameters. Results revealed that the curing time …


Nonlinear Fatigue Damage Of Cracked Cement Paste After Grouting Enhancement, Zhi Wang, Long Li, Shuaicheng Guo, Qingli Dai Jul 2018

Nonlinear Fatigue Damage Of Cracked Cement Paste After Grouting Enhancement, Zhi Wang, Long Li, Shuaicheng Guo, Qingli Dai

Michigan Tech Publications

Grouting reinforcement is an important part of modern engineering and has grown in popularity due to the benefits of grouting enhancement on cyclic loading. Understanding the fatigue mechanism of grouting-enhanced structures is vital to the design and the long-term stability analysis of such structures. In this study, the fatigue mechanical properties of cracked cement paste after epoxy resin grouting enhancement under different cyclic conditions were investigated in the laboratory and an inverted S-shaped curve was proposed to describe the damage accumulation. The test results indicated that the fatigue axial deformation can be divided into three stages: the initial stage, constant …


Effects Of Titanate Coupling Agent On Engineering Properties Of Asphalt Binders And Mixtures Incorporating Lldpe-Caco3 Pellet, Mohd Rosli Mohd Hasan, Zhanping You, Mohd Khairul Idham Mohd Satar, Muhammad Naqiuddin Mohd Warid, Nurul Hidayah Mohd Kamaruddin, Dongdong Ge, Ran Zhang Jun 2018

Effects Of Titanate Coupling Agent On Engineering Properties Of Asphalt Binders And Mixtures Incorporating Lldpe-Caco3 Pellet, Mohd Rosli Mohd Hasan, Zhanping You, Mohd Khairul Idham Mohd Satar, Muhammad Naqiuddin Mohd Warid, Nurul Hidayah Mohd Kamaruddin, Dongdong Ge, Ran Zhang

Michigan Tech Publications

This study was initiated to evaluate the performance of asphalt binders and mixtures incorporating linear low-density polyethylene- calcium carbonate (LLDPE-CaCO3) pellet, either with or without titanate coupling agent. The detailed manufacturing process of modifier pellets was displayed. The coupling agent was used to enhance the cross-linking between materials by means of winding up covalent bonds or molecule chains, thus improving the performance of composites. In the preparation of modified bitumen, the preheated asphalt binder was mixed with the modifiers using a high shear mixer at 5000 rpm rotational speed for 45 min. Experimental works were conducted to evaluate …


Laboratory Evaluation On Performance Of Compound-Modified Asphalt For Rock Asphalt/Styrene–Butadiene Rubber (Sbr) And Rock Asphalt/Nano-Caco3, Songtao Lv, Shuangshuang Wang, Tong Guo, Chengdong Xia, Jianglong Li, Gui Hou Jun 2018

Laboratory Evaluation On Performance Of Compound-Modified Asphalt For Rock Asphalt/Styrene–Butadiene Rubber (Sbr) And Rock Asphalt/Nano-Caco3, Songtao Lv, Shuangshuang Wang, Tong Guo, Chengdong Xia, Jianglong Li, Gui Hou

Michigan Tech Publications

As a natural modifier of asphalt, rock asphalt has been widely used to improve its thermal stability and aging resistance. However, the thermal cracking resistance of asphalt modified by rock asphalt is unsatisfactory. In order to improve the thermal cracking resistance in low temperature, two kinds of modifiers—styrene–butadiene rubber (SBR) and nano-CaCO3—were selected as the compound modifiers, and then implemented to improve the low-temperature performance of the binder. Then, compound asphalt modified by Buton rock asphalt (BRA) was chosen as the study subject. The thermal stability and aging resistance of asphalt modified by BRA, compound-modified asphalt by BRA/SBR, …


Assessment Of Soil Erosion Vulnerability In The Heavily Populated And Ecologically Fragile Communities In Motozintla De Mendoza, Chiapas, Mexico, Selene González-Morales, Alex Mayer, Neptalí Ramírez-Marcial Jun 2018

Assessment Of Soil Erosion Vulnerability In The Heavily Populated And Ecologically Fragile Communities In Motozintla De Mendoza, Chiapas, Mexico, Selene González-Morales, Alex Mayer, Neptalí Ramírez-Marcial

Michigan Tech Publications

Variability in physical rates and local knowledge of soil erosion was assessed across six rural communities in the Sierra Madre del Sur, Chiapas, Mexico. The average erosion rate estimated using the RUSLE model is 274 t ha-1 yr-1, with the estimated erosion rates ranging from 28 to 717 t ha-1 yr-1. These very high erosion rates are associated with high rainfall erosivity (17 000 MJ mm ha-1 h-1 yr-1) and steep slopes (mean slope Combining double low line 67 %). Many of the highest soil erosion rates are found in communities that are dominated by forestland, but where most of …


Rheological Behavior And Sensitivity Of Wood-Derived Bio-Oil Modified Asphalt Binders, Junfeng Gao, Hainian Wang, Zhanping You, Mohd Rosli Mohd Hasan, Yong Lei, Muhammad Irfan Jun 2018

Rheological Behavior And Sensitivity Of Wood-Derived Bio-Oil Modified Asphalt Binders, Junfeng Gao, Hainian Wang, Zhanping You, Mohd Rosli Mohd Hasan, Yong Lei, Muhammad Irfan

Michigan Tech Publications

The demand for bituminous materials is continuously growing; crude oil-based asphalt binders are non-renewable, and are facing rapid depletion. With the increase of petroleum-based asphalt prices, seeking an alternative, renewable material such as bio-asphalt has become a hot research topic. However, shortcomings in this research area have been identified, notably concerning the high-temperature performance of bio-asphalt at present. This research aims to comprehensively apply conventional tests to, and study the rheological behavior of, the high-temperature performances of bio-asphalt binders, i.e., by temperature and frequency sweeps, using a dynamic shear rheometer (DSR). It will also assess the chemical functional groups of …


Study On Components Determination And Performance Evaluation Of Ls Pre-Maintenance Agent, Yuxiang Tian, Biao Ma, Ke Tian, Ning Li, Xueyan Zhou May 2018

Study On Components Determination And Performance Evaluation Of Ls Pre-Maintenance Agent, Yuxiang Tian, Biao Ma, Ke Tian, Ning Li, Xueyan Zhou

Michigan Tech Publications

Adequate maintenance and taking active preventive measures can effectively prevent the early disease of asphalt pavements before significant damage occurs. By developing a light screening preventive maintenance agent (LS pre-maintenance agent) for strong ultraviolet (UV) radiation areas, based on the asphalt aging and regeneration mechanism, we analyzed the function and basic components and determined the optimum components ratio based on the best proportion of penetrant and solvent oil for solubility. The optimum ratio for quick-drying and long-term storage ability is the mass ratio of rock asphalt, reducing agent, penetrant, and solvent oil, which is 30:20:20:30. The light-shield agent is 5% …


Characteristics Of Moduli Decay For The Asphalt Mixture Under Different Loading Conditions, Songtao Lv, Xiyan Fan, Chengdong Xia, Jianlong Zheng, Dong Chen, Lingyun You May 2018

Characteristics Of Moduli Decay For The Asphalt Mixture Under Different Loading Conditions, Songtao Lv, Xiyan Fan, Chengdong Xia, Jianlong Zheng, Dong Chen, Lingyun You

Michigan Tech Publications

In order to explore the moduli decay patterns of asphalt mixtures under different loading conditions, the nonlinear fatigue damage model was implemented in order to simulate the moduli decay patterns. Then, the direct tensile, indirect tensile, and uniaxial compression fatigue tests were employed under four kinds of stress levels with four parallel tests. The specimens of AC-13C Styrene-butadiene-styrene (SBS) modified mixtures were manufactured. Based on the test results, the decay patterns of the moduli during fatigue tests under different stress states were revealed, and the parameters of the damage model under different test conditions were obtained. By changing the values …


Fatigue Equation Of Cement-Treated Aggregate Base Materials Under A True Stress Ratio, Songtao Lv, Chaochao Liu, Jingting Lan, Hongwei Zhang, Jianlong Zheng, Zhanping You Apr 2018

Fatigue Equation Of Cement-Treated Aggregate Base Materials Under A True Stress Ratio, Songtao Lv, Chaochao Liu, Jingting Lan, Hongwei Zhang, Jianlong Zheng, Zhanping You

Michigan Tech Publications

The objective of this article is to establish a fatigue equation based on the true stress ratio for cement-treated aggregate base materials. The true stress ratio herein means the ratio of the stress and the true strength of the cement-treated aggregate base materials related to loading rates and curing times. The unconfined compressive strength tests and compressive resilience modulus tests were carried out under various loading rates and curing times of 3, 7, 14, 28, 60, 90 days, respectively. According to the test results, the relationship between the unconfined compressive strength (a mix design parameter in China) and the compressive …


Advanced Paving Materials And Technologies, Zhanping You, Qingli Dai, Feipeng Xiao Apr 2018

Advanced Paving Materials And Technologies, Zhanping You, Qingli Dai, Feipeng Xiao

Michigan Tech Publications

No abstract provided.


Advanced Pavement Materials For Sustainable Transportation Infrastructure, Zhanping You, Meor O. Hamzah, Hainian Wang, Aboelkasim Diab, Qingli Dai Feb 2018

Advanced Pavement Materials For Sustainable Transportation Infrastructure, Zhanping You, Meor O. Hamzah, Hainian Wang, Aboelkasim Diab, Qingli Dai

Michigan Tech Publications

Many road managers and stakeholders are looking for more and better options for the construction and maintenance of flexible and rigid pavements. Well-designed strategies for pavement construction and maintenance have attracted the interests of researchers since a large number of existing pavements are facing deterioration all over the world. The selection and engineering properties of paving materials are crucial factors affecting the durability and therefore demanding standards of sustainability of the constructed pavement. Researchers worldwide are putting extensive efforts to develop and promote advanced pavement materials and structures for constructing and maintaining sustainable pavements. Pavement materials that can improve durability, …


Evaluation Of Well Designs To Improve Access To Safe And Clean Water In Rural Tanzania, Aminata Kilungo, Linda Powers, Nathan B. Arnold, Kelli Marie Whelan, Kurt Paterson, Dale Young Jan 2018

Evaluation Of Well Designs To Improve Access To Safe And Clean Water In Rural Tanzania, Aminata Kilungo, Linda Powers, Nathan B. Arnold, Kelli Marie Whelan, Kurt Paterson, Dale Young

Michigan Tech Publications

The objective of this study was to examine three well designs: drilled wells (20–30 m deep), closed dug wells (>5 m deep), and hand-dug open wells (<5 m deep), to determine the water quality for improving access to safe and clean water in rural communities. Heterotrophic plate count (HPC), total coliforms (TC), Escherichia coli (E. coli) and turbidity, were used to assess the water quality of 97 wells. Additionally, the study looked at the microflora diversity of the water, focusing on potential pathogens using outgrowth, PCR, and genome sequencing for 10 wells. Concentrations of TC for the open dug wells (4 × 104 CFU/100 mL) were higher than the drilled (2 × 103 CFU/100 mL) and closed dug wells (3 × 103 CFU/100 mL). E. coli concentration for drilled and closed dug wells was <22 MPN (most probable number)/100 mL, but higher for open wells (>154 MPN/100 mL). The drilled well turbidity (11 NTU) was within the standard deviation of the closed well (28 NTU) compared to open dug wells (49 NTU). Drilled and closed wells had similar microbial diversity. There were no …


2018 Civil And Environmental Engineering Department News, Department Of Civil And Environmental Engineering, Michigan Technological University Jan 2018

2018 Civil And Environmental Engineering Department News, Department Of Civil And Environmental Engineering, Michigan Technological University

Department of Civil, Environmental, and Geospatial Engineering Newsletters

Table of Contents

  • External Awards
  • Faculty Feature
  • Student Features
  • Outreach
  • Alumni Feature
  • CEE Academy
  • Internal Awards
  • Donors


Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner Jan 2018

Viability Of Graywater Reuse In Lesotho’S Lowland Agricultural District, Ryan Wagner

Dissertations, Master's Theses and Master's Reports

Water security has become a large issue with populations rising and weather patterns changing to drier and hotter conditions in southern Africa. Lesotho, a mountainous country landlocked by South Africa, is responsible for a large amount of the rainfall in southern Africa. As such, Lesotho provides water to South Africa in exchange for national economic growth. Lesotho, however, is also prone to droughts and with water reserves being sold to South Africa, water security has become a national issue. This study looked at Lesotho’s current water use habits and found that graywater reuse could lead to much more available water. …


Polychlorinated Biphenyls (Pcbs): A Legacy Of Contamination In Michigan's Rivers, Emily Shaw Jan 2018

Polychlorinated Biphenyls (Pcbs): A Legacy Of Contamination In Michigan's Rivers, Emily Shaw

Dissertations, Master's Theses and Master's Reports

Polychlorinated biphenyls (PCBs) are ubiquitous contaminants worldwide and are the most frequent contaminant at US and bi-national Great Lakes areas of concern (AOCs). This study evaluated existing evidence to answer the questions: how does total PCB contamination compare between fish species, are there spatial patterns in PCB contamination in fish species, and have our remediation efforts been effective? Using multi-variate statistics (e.g. analysis of variance (ANOVA), principal component analysis (PCA), and multiple linear regression (MLR)), this research evaluated Michigan Department of Environmental Quality (MDEQ) fish contaminant monitoring data to attempt to answer the questions above.

PCB concentrations between the species …


A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks Jan 2018

A Model To Predict Concentrations And Uncertainty For Mercury Species In Lakes, Ashley Hendricks

Dissertations, Master's Theses and Master's Reports

To increase understanding of mercury cycling, a seasonal mass balance model was developed to predict mercury concentrations in lakes and fish. Results indicate that seasonality in mercury cycling is significant and is important for a northern latitude lake. Models, when validated, have the potential to be used as an alternative to measurements; models are relatively inexpensive and are not as time intensive. Previously published mercury models have neglected to perform a thorough validation. Model validation allows for regulators to be able to make more informed, confident decisions when using models in water quality management. It is critical to quantify uncertainty; …


Factors Contributing To Elevated Concentrations Of Mercury And Pcbs In Fish In The Inland Lakes Of Michigan's Upper Peninsula And Lake Superior, Mugdha Priyadarshini Jan 2018

Factors Contributing To Elevated Concentrations Of Mercury And Pcbs In Fish In The Inland Lakes Of Michigan's Upper Peninsula And Lake Superior, Mugdha Priyadarshini

Dissertations, Master's Theses and Master's Reports

Mercury (Hg) pollution adversely affects ecosystems and human health. Mercury in the form of methylmercury (MeHg) bioaccumulates in aquatic ecosystems, thereby affecting fish, fish-eating wildlife and humans. The goal of this research was to clarify the effects of environmental factors on MeHg concentrations in fish in the inland lakes of the Upper Peninsula of Michigan. Of the 74 lakes for which data were available, 56 had fish mercury concentrations above the water quality guideline. Multivariate statistical analyses indicated different factors affect fish Hg concentrations in large and small lakes.

Polychlorinated biphenyl (PCB) compounds are a class of persistent, bioaccumulative and …


Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi Jan 2018

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi

Dissertations, Master's Theses and Master's Reports

Cladophora glomerata is a filamentous green alga native to the Great Lakes. However, its nuisance growth in phosphorus rich waters negatively affects the lakes’ aesthetic and water quality. The Great Lakes Cladophora Model (GLCM) v1, developed in 1982, was the first mechanistic model to simulate Cladophora growth basing phosphorus availability and environmental conditions followed by Cladophora Growth Model and GLCM v2. In this study, the light and temperature mediation factors for Cladophora net growth are revised as a necessary step prior to the development of a self-shading algorithm. The concept of a fixed-value, maximum achievable biomass (carrying capacity) employed in …


Evaluation Of Driver Behavior At Highway-Railroad Grade Crossings Based On Environmental Conditions And Driver Demographics, Alawudin Salim Jan 2018

Evaluation Of Driver Behavior At Highway-Railroad Grade Crossings Based On Environmental Conditions And Driver Demographics, Alawudin Salim

Dissertations, Master's Theses and Master's Reports

Although the total number of highway-railroad grade crossing (HRGC) accidents has significantly decreased in recent decades, they remain as one of the highest causes of injuries and fatalities in rail transportation. It is known that driver behavior is the leading cause for accidents at HRGCs, but there is less understanding on the reason for these inappropriate behaviors. This research uses the Strategic Highway Research Program 2 Naturalistic Driving Study (SHRP 2 NDS) data and a behavior scoring methodology developed at Michigan Technological University (Michigan Tech), to evaluate driver behavior when traversing HRGCs. More specifically, it uses a two-sample t-test to …


Predicting The Organic Compound Degradation In Aqueous-Phase Ultraviolet (Uv) And Uv-Based Advanced Oxidation Processes, Erica Coscarelli Jan 2018

Predicting The Organic Compound Degradation In Aqueous-Phase Ultraviolet (Uv) And Uv-Based Advanced Oxidation Processes, Erica Coscarelli

Dissertations, Master's Theses and Master's Reports

Clean safe drinking water is vital for society. With increasing water scarcity and the increased numbers of chemicals identified in waterways, it is important for us to fully understand how to destroy contaminants of concern and prevent potentially hazardous byproducts that may be produced from the degradation processes. Little is known about how nitrogen containing organics behave and degrade in current water treatment systems and therefore their role in water reuse. N-nitrosodimethylamine (NDMA), is carcinogenic and is being formed during conventional chlorination of drinking water. Ultraviolet (UV) photooxidation has been shown to degrade NDMA, but the degradation pathways and their …


Optimizing Chlorine Disinfection By Chlorine Injection Location And Pipe Diameter Selection In A Water Distribution System, Margaret Neff Jan 2018

Optimizing Chlorine Disinfection By Chlorine Injection Location And Pipe Diameter Selection In A Water Distribution System, Margaret Neff

Dissertations, Master's Theses and Master's Reports

Due to a variety of factors chlorination is common water disinfectant for community-scale distribution systems. The town of Suyo, Peru was already equipped with a gravity fed water system and drip chlorinator which achieved 4-log inactivation of viruses throughout the town, however, it was not providing 3-log inactivation of giardia cysts at all points of the system.

This project used an EPANET model to determine and compare the potential benefits of changes which could be made to the pre-existing water system in Suyo.

The model was used to compare current operating conditions of the Suyo system, 1.5 mg/L chlorine addition …


Two Pumps, One Volcano: An Epanet Feasbility Study Of Connecting Two Groundwater Pumps In Rural Coastal Communities In West Ambae, Vanuatu, Helen Amiri Jan 2018

Two Pumps, One Volcano: An Epanet Feasbility Study Of Connecting Two Groundwater Pumps In Rural Coastal Communities In West Ambae, Vanuatu, Helen Amiri

Dissertations, Master's Theses and Master's Reports

In situations where groundwater supply shows vulnerability, improving water distribution network resiliency can be desirable. To do so, one water source can be linked with another to provide a redundant source.

On the South Pacific island of Ambae, the water demands of its residents routinely exceeded supply. Residents had traditionally used rainwater collection as their sole water supply source. In 2017, groundwater drilling operations created an alternative water supply at two community institutions, Ndui Ndui Health Center and Londua Junior Secondary School. One borehole went dry during pump testing; the feasibility of linking these two boreholes is investigated herein.

EPANET …


Understanding Large-Scale Natural Mine Water-Geologic Formation Systems For Geothermal Applications, Ting Bao Jan 2018

Understanding Large-Scale Natural Mine Water-Geologic Formation Systems For Geothermal Applications, Ting Bao

Dissertations, Master's Theses and Master's Reports

Geothermal energy recovery from flooded mines has been gaining momentum worldwide. Numerous mines are flooded after their closure, either naturally or artificially, in which the water in the mines can be heated by the surrounding geologic formations due to geothermal gradients, leading to sizeable man-made reservoirs of warm water. Such mine water, therefore, can be treated as a renewable geothermal resource for heating/cooling buildings, which has the potential to benefit over millions of people in the United States and much more around the world. Though some real projects and/or installations launched worldwide for the use of flooded mines for geothermal …


Transient Simulations Of Freshwater Lens Depletion In Response To A Range Of Sea Level Rise Rates And Climate Gradients, Qiuyuan Nan Jan 2018

Transient Simulations Of Freshwater Lens Depletion In Response To A Range Of Sea Level Rise Rates And Climate Gradients, Qiuyuan Nan

Dissertations, Master's Theses and Master's Reports

The freshwater lens in the island can become the only freshwater resources in some regions. Numerical simulations are used to determine freshwater lens volume and average concentration is in response to the range of sea-level rise rates and climate gradients. The sea-level rise rates (0.56 mm/yr, 6.22 mm/yr, and 11.78 mm/yr) are selected for projected and the climate gradient is computed from the islands in the Bahamian archipelago (Inagua, San Salvador, and Grand Bahamas) in the north, central and south. Based on the simulation results, all cases presented the upward trend of the average salinity but have the oscillation in …


Evaluation, Improvement, And Application Of Models Of Environmental Fate And Transport Of Atmosphere-Surface Exchangeable Pollutants (Aseps), Tanvir Khan Jan 2018

Evaluation, Improvement, And Application Of Models Of Environmental Fate And Transport Of Atmosphere-Surface Exchangeable Pollutants (Aseps), Tanvir Khan

Dissertations, Master's Theses and Master's Reports

Certain toxic, semivolatile chemicals, also known as atmosphere-surface exchangeable pollutants (ASEPs) are emitted into the environment from anthropogenic activities and natural sources. This dissertation focused on the (i) evaluation and improvement of dry particle deposition and atmosphere-surface exchange parameterizations of ASEPs for use in chemical transport models (CTMs), and (ii) application of a dynamic multimedia model to examine recovery of Lake Superior from historical inputs of polychlorinated biphenyl (PCB) compounds (a class of ASEPs) contamination.

Current knowledge has been inadequate to propose quantitative measures of the relative performance of available dry particle deposition parameterizations. In Chapter 1 of this dissertation, …