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Full-Text Articles in Civil and Environmental Engineering

An Analysis Of Using Error Metrics To Determine The Accuracy Of Modeled Historical Streamflow On A Global Scale, Elise Katherine Jackson Apr 2018

An Analysis Of Using Error Metrics To Determine The Accuracy Of Modeled Historical Streamflow On A Global Scale, Elise Katherine Jackson

Theses and Dissertations

Streamflow data is used throughout the world in applications such as flooding, agriculture, and urban planning. Understanding daily and seasonal patterns in streamflow is important for decision makers, so that they can accurately predict and react to seasonal changes in streamflow for the region. This understanding of daily and seasonal patterns has historically been achieved through interpretation of observed historical data at stream reaches throughout the individual regions. Developing countries have limited and sporadic observed stream and rain gage data, making it difficult for stakeholders to manage their water resources to their fullest potential. In areas where observed historical data …


Effects Of Surface Treatments On National Bridge Inventory Condition Ratings For Concrete Bridge Decks In Utah, John Taani De Leon Apr 2018

Effects Of Surface Treatments On National Bridge Inventory Condition Ratings For Concrete Bridge Decks In Utah, John Taani De Leon

Theses and Dissertations

Although the application of surface treatments on bridge decks is expected to positively impact bridge deck condition, the effectiveness of specific surface treatments on extending bridge deck life has not yet been quantified on Utah bridge decks. Therefore, the objectives of this research were to develop and analyze deterioration curves for bare concrete bridge decks and decks with specific treatments commonly used in Utah. The scope of this study was determined by the types and extent of electronically available data, including selected static inventory information; maintenance, rehabilitation, and reconstruction histories; and National Bridge Inventory (NBI) condition ratings for the bridge …


Measuring And Calculating Current Atmospheric Phosphorous And Nitrogen Loadings On Utah Lake Using Field Samples, Laboratory Methods, And Statistical Analysis: Implication For Water Quality Issues, Jacob Milton Olsen Apr 2018

Measuring And Calculating Current Atmospheric Phosphorous And Nitrogen Loadings On Utah Lake Using Field Samples, Laboratory Methods, And Statistical Analysis: Implication For Water Quality Issues, Jacob Milton Olsen

Theses and Dissertations

Atmospheric nutrient loading and transport though precipitation and dry deposition is one of the least understood yet one of the most important pathways of nutrient transport into many lakes. These nutrients, phosphorus and nitrogen, are essential for aquatic life and often play major roles in algae blooms that occur in lakes and reservoirs. Often heavy algal growth intensifies a variety of water quality problems. Utah Lake may be even more susceptible to atmospheric deposition due to its large surface area to volume ratio and proximity to Great Basin dust sources. In this study, eight months of atmospheric deposition data were …


Chloride Concentration And Blow-Through Analysis For Concrete Bridge Decks Rehabilitated Using Hydro-Demolition, Elizabeth Ashleigh Roper Apr 2018

Chloride Concentration And Blow-Through Analysis For Concrete Bridge Decks Rehabilitated Using Hydro-Demolition, Elizabeth Ashleigh Roper

Theses and Dissertations

The objectives of this research were 1) to investigate the effects of hydrodemolition treatment timing on chloride concentration profiles in concrete bridge decks for depths of concrete removal below the top mat of reinforcing steel and 2) to investigate factors that influence the occurrence of blow-throughs in concrete bridge decks when hydrodemolition is used. The research results are intended to provide engineers with guidance about the latest timing of hydrodemolition that can maintain a chloride concentration level below 2.0 lb of chloride per cubic yard of concrete at the levels of both the top and bottom mats of reinforcing steel, …


Effect Of Inclined Loading On Passive Force-Deflection Curves And Skew Adjustment Factors, Joshua Rex Curtis Apr 2018

Effect Of Inclined Loading On Passive Force-Deflection Curves And Skew Adjustment Factors, Joshua Rex Curtis

Theses and Dissertations

Skewed bridges have exhibited poorer performance during lateral earthquake loading in comparison to non-skewed bridges (Apirakvorapinit et al. 2012; Elnashai et al. 2010). Results from numerical modeling by Shamsabadi et al. (2006), small-scale laboratory tests by Rollins and Jessee (2012), and several large-scale tests performed by Rollins et al. at Brigham Young University (Franke 2013; Marsh 2013; Palmer 2013; Smith 2014; Frederickson 2015) led to the proposal of a reduction curve used to determine a passive force skew reduction factor depending on abutment skew angle (Shamsabadi and Rollins 2014). In all previous tests, a uniform longitudinal load has been applied …


Comprehensive Comparison Of Steel Framed Fabric And Conventionally Constructed Aircraft Hangars, Justin M. Iungerich Mar 2018

Comprehensive Comparison Of Steel Framed Fabric And Conventionally Constructed Aircraft Hangars, Justin M. Iungerich

Theses and Dissertations

Through the life of the United States Air Force (USAF), the accepted method for constructing permanent aircraft hangars is the use of materials such as steel and concrete. However, the emerging type of construction known as steel framed fabric (SFF) construction shows potential to meet the requirements of the USAF at a lower life-cycle cost and with faster construction delivery. A comprehensive comparison to conventional hangars is conducted through the means of an extensive literature review, case study analysis, structural analysis with the use of finite element analysis (FEA) software, and a life-cycle cost comparison. Through examination of Department of …


Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A. J. Edlund Mar 2018

Quantifying Permafrost Extent, Condition, And Degradation Rates At Department Of Defense Installations In The Arctic, Christopher A. J. Edlund

Theses and Dissertations

The DoD is planning over $500M in military construction on Eielson Air Force Base (AFB) within the next three years. This construction program will expand the footprint of facilities and change parts of the storm water management scheme, which may have second order effects on the underlying permafrost layer. These changes in permafrost will drive engineering decision making at local and regional levels, and help shape the overall strategy for military readiness in the Arctic. Little site-specific knowledge exists on the human caused effects to permafrost at this location. In 2016, the permafrost degradation rates at Eielson AFB were modeled …


A Surprising Symbiosis: Examining The Mutualism In Department Of Defense Conservation Partnerships, Andrew J. Lankow Mar 2018

A Surprising Symbiosis: Examining The Mutualism In Department Of Defense Conservation Partnerships, Andrew J. Lankow

Theses and Dissertations

Because of the DoD’s unique and significant role in the conservation of natural resources, military leaders and natural resource managers need a trail guide to frame interagency collaboration in a way that shapes productive partnerships. The purpose of this research was to examine successful DoD conservation partnerships in order to identify key success factors (KSFs) and the most prominent challenges faced, and how those characteristics enable the accomplishment of each partner’s objectives. The research questions were answered through a comprehensive literature review and the use of the multiple-case study method. 19 key informants from three installations participated in semi-structured interviews, …


Defining Success In Air Force Infrastructure Asset Management Through Use Of The Delphi Method, Brendan J. Maestas Mar 2018

Defining Success In Air Force Infrastructure Asset Management Through Use Of The Delphi Method, Brendan J. Maestas

Theses and Dissertations

Asset Management has a history of policy mandates within the US Government dating back to 1990’s. In order to accomplish these many directives, the Air Force Civil Engineer community has adopted a mindset and framework commonly referred to as Asset Management. Despite numerous references and guidance to establish Asset Management principles, the Air Force has not yet developed a clear and concise way to define or measure overarching success in Asset Management. This research effort focuses on closing the knowledge gap between issued policy and implementation. It examines Asset Management implementation efforts in other government agencies, private industries, and in …


Cost And Performance Difference Of High Performance Sustainable Buildings, Philip A. Ramsey Mar 2018

Cost And Performance Difference Of High Performance Sustainable Buildings, Philip A. Ramsey

Theses and Dissertations

Varying legislation and executive orders coupled with needs for energy resiliency have led the United States Air Force to pursue sustainable construction. The limited understandings of initial costs to implement these changes have contributed to poor project cost estimating and changed implementation of legal requirements. A student t-test for populations with unequal variance was accomplished on the final normalized contract cost of 1628 Air Force Military Construction (MILCON) projects executed between 2002 and 2017. Future design considerations for net zero energy buildings were compiled from a net zero energy residential community in Fontana, California. There was no statistically significant difference …


Land Cover Influences On Airborne Noise Propagation At Usaf Installations, Ariel L. Waiters Mar 2018

Land Cover Influences On Airborne Noise Propagation At Usaf Installations, Ariel L. Waiters

Theses and Dissertations

Mitigation of aircraft noise and encroachment by residential areas at various U.S. military installations remains a challenge and hampers effective military operations. The Air Force has established standard practices that utilize computational noise models to generate and display noise propagation from military installations. Despite great advances in models and mitigation action plans, the current USAF Noisemap modeling tool and methods do not consider the effects of variation in land cover. Moreover, such limitations could greatly affect the accuracy of predicting aircraft noise pollution. The standard modeling method assumes a ground cover impedance of 225 Kpa*s/m2, which …


Evaluating Contingency Construction Methods: A Delphi Study, William E. Bentley Mar 2018

Evaluating Contingency Construction Methods: A Delphi Study, William E. Bentley

Theses and Dissertations

The purpose of this research was to evaluate which existing RED HORSE vertical construction system was “best” suited for contingency operations and the relative pros/cons/challenges associated with each. RED HORSE units, having existed for over 50 years, currently have 4 active duty squadrons currently employed overseas in multiple military contingency environments. Based on site visits, it was established that the Ultimate Building Machine (UBM)/K-Span, Professionally Engineered Buildings (PEB), and the FrameCAD system are the three most prevalent vertical construction systems/methods in use by RED HORSE. Fourteen Subject Matter Experts (SME) from across the Air Force participated in a Delphi study …


The Effect Of Ms2 Bacteriophage On The Activity And Performance Of Activated Sludge, Sean M. Stuntz Mar 2018

The Effect Of Ms2 Bacteriophage On The Activity And Performance Of Activated Sludge, Sean M. Stuntz

Theses and Dissertations

As a medical waste product, the MS2 bacteriophage has been discharged into wastewater distribution and treatment networks. To categorize its impact to suspended growth treatment methods, this research investigated the effect of the MS2 bacteriophage on activated sludge through a series of respirometry tests. The effects of MS2 bacteriophage at a concentration of 3.2x108 PFU/mL were assessed by determining peak O2 consumption, cumulative O2 consumption, molar CO2/O2 ratios, and shape factors. None of the MS2 samples caused statistically significant effects on the peak or cumulative O2 consumption. The molar CO2/O2 …


Mechanical Properties Of Inconel 718 Processed Using Electron Beam Free Form Fabrication (Ebf3), Brent R. Waters Mar 2018

Mechanical Properties Of Inconel 718 Processed Using Electron Beam Free Form Fabrication (Ebf3), Brent R. Waters

Theses and Dissertations

Electron beam freeform fabrication (EBF3) is a rapid metal deposition process that works efficiently with the wieldable alloy Inconel 718 (IN 718). EBF3 is a developing additive manufacturing (AM) process that can manufacture IN 718 parts directly from computer aided design (CAD) data. EBF3 can produce parts significantly faster and more energy efficient than competing IN 718 AM technologies. The EBF3 process utilizes metal wire feedstock which is induced into a molten pool using a focused electron beam in a vacuum environment. This allows parts to be built layer by layer, creating intricate shapes that …


Occupational Noise Dose Reduction Via Behavior Modification Using In-Ear Dosimetry Among Usaf Personnel Exposed To Continuous Impulse Noise, Jesse A. Trawick Mar 2018

Occupational Noise Dose Reduction Via Behavior Modification Using In-Ear Dosimetry Among Usaf Personnel Exposed To Continuous Impulse Noise, Jesse A. Trawick

Theses and Dissertations

The purpose of this research was to investigate the use of in-ear noise dosimetry and worker feedback to reduce noise exposures among combat arms instructors and heavy equipment operators in the Air Force. Specifically, this thesis sought to determine how effectively hearing protection devices (HPDs) are being utilized currently, and whether providing at-ear noise exposure data to workers results in reduced noise exposures or changes in worker attitude. These questions were addressed by performing a six-month field study using dosimeters to record worker noise exposures under HPDs. Subjects served as their own control, receiving feedback in only the latter half …


Rotational Stiffness Models For Shallow Embedded Column-To-Footing Connections, Ashley Lauren Sadler Mar 2018

Rotational Stiffness Models For Shallow Embedded Column-To-Footing Connections, Ashley Lauren Sadler

Theses and Dissertations

Shallow embedded steel column connections are widely used in steel buildings; however, there is insufficient research about this connection type to understand the actual rotational stiffness that the connection provides. Shallow embedded steel columns are when a steel column is anchored to the foundation slab and then unreinforced concrete is poured around the base plate and the base of the column. This thesis seeks to further quantify the rotational stiffness available in this type of connection due to the added concrete and improve an existing model in order to represent the rotational stiffness. Existing data from two series of experiments …


The Use Of Evidence-Based Design In Hospital Renovation Projects, David S. Whitaker Mar 2018

The Use Of Evidence-Based Design In Hospital Renovation Projects, David S. Whitaker

Theses and Dissertations

Since the 1960s, researchers have been exploring how the design of the built environment impacts the health and well-being of occupants and users. By the 1980s, further research began to focus on healthcare facilities in particular and how design could influence patient healing and medical staff performance (Alfonsi, 2014). Evidence-Based Design (EBD) is "the process of basing decisions about the built environment on credible research to achieve the best possible outcomes" (CHD, 2016). The desired outcomes of Evidence-Based Design recommendations include improvements in the following: patient healing, patient experience and comfort, medical staff performance, and medical staff job satisfaction (CHD, …


A Detailed Hydrodynamic Study To Help Community Based Resiliency Planning Under Extreme Climatic And Weather Events, Md Golam Rabbani Fahad Feb 2018

A Detailed Hydrodynamic Study To Help Community Based Resiliency Planning Under Extreme Climatic And Weather Events, Md Golam Rabbani Fahad

Theses and Dissertations

The State of New Jersey is particularly vulnerable to extreme weather and climatic events. This study concentrates on spatial and temporal vulnerability of these events using climate and hydrodynamic modelling. The first chapter focuses on historical climatic trend of temperature and precipitation as well as the future scenarios using 10 bias corrected climate model output considering high end emission scenario derived from Coupled Model Intercomparison Project Phase 5 (CMIP5). In the second chapter a coastal hydrodynamic model called ADCIRC-2DDI was implemented to assess the impact of hurricanes in the Western North Atlantic (WNAT) model domain. The efficiency of the model …


Analysis Of Cross-Cultural Training Provided To United States Air Force Civil Engineer Officers, And How Engineering Efforts Are Affected On Overseas Air Force Installations: A Delphi Study, Bianca E. Boney Feb 2018

Analysis Of Cross-Cultural Training Provided To United States Air Force Civil Engineer Officers, And How Engineering Efforts Are Affected On Overseas Air Force Installations: A Delphi Study, Bianca E. Boney

Theses and Dissertations

U.S. military personnel perform a wide array of roles and missions at locations all over the world. As such, this research investigates and describes the current process of cultural training, its adequacy, and examines how cultural differences and collaboration efforts may impede or enhance project management and engineering efforts. This qualitative analysis is conducted through a Delphi study of U.S. Air Force officers consisting of 15 subject matter experts (SMEs) with experiences from 13 different countries. All reported to have daily to weekly interactions with locals and foreign partners due to job requirements; however, no set standard of cultural training …


Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu Jan 2018

Hydrothermal Carbonization Of Food Waste For Nutrient Recovery And Reuse, Ifeolu M. Idowu

Theses and Dissertations

Food waste represents a rather large and currently underutilized source of potentially available and reusable nutrients. Laboratory-scale experiments evaluating the hydrothermal carbonization of food wastes collected from restaurants were conducted to understand how changes in feedstock composition and carbonization process conditions influence primary and secondary nutrient fate. Results from this work indicate that at all evaluated reaction times and temperatures, the majority of nitrogen, calcium, and magnesium remain integrated within the solid-phase, while the majority of potassium and sodium reside in the liquid-phase. The fate of phosphorus is dependent on reaction times and temperatures, with solid-phase integration increasing with higher …


Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi Jan 2018

Understanding Geopolymerization Process For Enhancement Of Mechanical Properties Of Fly Ash Based-Geopolymer Concrete, Lateef Najeh Assi

Theses and Dissertations

Concrete is a major construction material that is largely made up of cement. Unfortunately, the manufacturing process for the cement currently used to produce concrete releases a great deal of CO2, which endangers the environment. Hence, finding alternatives to ordinary Portland cement is of extreme importance. The intellectual contribution of this dissertation is the development of an improved understanding of the geopolymerization process so that the compressive strength of cement can be maximized while the need for external heating is minimized. The intent is to create a substance to replace commonly used cement without sacrificing other beneficial properties. The first …


Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar Jan 2018

Assessing Exposure To Occupants In An Indoor Space Due To Expirated Aerosols: Application Of Computational Fluid Dynamics, Firoza Binte Omar

Theses and Dissertations

Indoor environment is an important issue for the well-being of the society. In the United States more than 90% people spend their time indoor, indoor air pollution is more culpable than the pollution outside air. Two third of US businesses lose more than $100,000 per year due to workplace related illness. The trend of sharing the work space has an impact on total sick leaves in a company. Infectious particles released by a flu sufferer’s sneezing, coughing or even laughing can be a vital source. A thorough analysis on infectious particles’ transmission and air flow of the space can provide …


Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed Jan 2018

Impact Of Critical Path Method (Cpm) Of Scheduling On On-Time Completion Of Transportation Projects, Fahim Ahmed

Theses and Dissertations

This study addresses the effectiveness of Critical Path Method (CPM) scheduling on project delivery. Specifically, the on-time completion of projects with and without a CPM schedule is explored. The paper uses data from 2,097 South Carolina transportation projects let after February 2008 and substantially completed by August 2015. The delay analysis uses the original contract completion date as well as the completion date adjusted by change orders. Chi-Squared tests are used to examine the relationship between CPM scheduled projects and delayed projects, and t-tests are used to compare the mean delay (in days) between CPM scheduled and unscheduled projects. The …


Evaluation Of Sonocatalytic Degradation Of Ibuprofen And Sulfamethoxazole In The Presence Of Various Catalysts, Yasir Alhamadani Jan 2018

Evaluation Of Sonocatalytic Degradation Of Ibuprofen And Sulfamethoxazole In The Presence Of Various Catalysts, Yasir Alhamadani

Theses and Dissertations

Over the last two decades, large quantities of products, such as medicines, disinfectants, and personal care products, have been released into surface waters and wastewater treatment facilities by the pharmaceutical and chemical industries which have come to the attention of scientists with regard to their impacts on life in lakes, rivers, and groundwater. Among various types of treatment processes, ultrasonic (US) treatment process was used in this study to investigate the effect catalysts and removal of selected pharmaceutical’s (PhACs) compounds (ibuprofen (IBP) and sulfamethoxazole (SMX)). Carbon nanomaterials (CNMs) have become candidates for numerous applications in nanocomposites, microelectric devices, sensors, energy …


Acoustic Emission Detection In 304h Stainless Steel Due To Intergranular Stress Corrosion Cracking, Joseph W. Hill Jan 2018

Acoustic Emission Detection In 304h Stainless Steel Due To Intergranular Stress Corrosion Cracking, Joseph W. Hill

Theses and Dissertations

Storage of spent nuclear fuel has become problematic in past decades due to delayed completion of long-term repositories for various reasons. Temporary storage containers called Dry Cask Storage Systems (DCSS) made of stainless-steel and surrounded by reinforced concrete have been in use but are exceeding their designed usage periods. Defects in canisters can be exacerbated in climates susceptible to high humidity and salinity levels. As inspection and relicensing of DCSS increases, more efficient monitoring techniques could save nuclear facilities valuable time and resources. Crack detection of the canister walls or welds in real time may be possible utilizing acoustic emission …


Probabilistic Multilevel Constitutive Model Of The Compressive Strength Of Hardened Cement Paste Reinforced With Mwcnts, Yohanna Mejia Cruz Jan 2018

Probabilistic Multilevel Constitutive Model Of The Compressive Strength Of Hardened Cement Paste Reinforced With Mwcnts, Yohanna Mejia Cruz

Theses and Dissertations

Constitutive models available in the literature typically describe the compressive strength of ordinary Portland cement paste (OPC) in a deterministic fashion, in some cases as a function of variables such as W/C, porosity, and the clinker chemical composition. The significant effect of the proportion of W/C on the final strength, porosity and density have been reported in several works in material science. Some studies have shown that the addition of MWCNTs can also modify the microstructure of cement significantly, and improve compressive strength and other mechanical and physical properties. In principle, W/C, MWCNTs addition, porosity, density, and compressive strength are …


Meso-Scale Simulation Of Size-Dependent Shear Behavior In Glass Fiber Reinforced Polymer Reinforced Concrete Beams Without Stirrups, Sina Khodaie Jan 2018

Meso-Scale Simulation Of Size-Dependent Shear Behavior In Glass Fiber Reinforced Polymer Reinforced Concrete Beams Without Stirrups, Sina Khodaie

Theses and Dissertations

There is extensive experimental evidence of the decrease in the shear stress at failure at increasing effective depths in concrete beams reinforced with glass fiberreinforced polymer (GFRP) bars without shear reinforcement. An important practical implication is that extrapolating strength values from typical laboratory-scaled experiments to design larger members may be misleading. The complexity of the underlying mechanics is reflected in the difficulty of using commercially available numerical tools to accurately estimate shear strength irrespective of beam size. This dissertation presents research on a Lattice Discrete Particle Model (LDPM) based model to simulate the response of scaled slender GFRP reinforced concrete …


Development Of Models And Solution Methods For Different Drayage Applications, Samaneh Shiri Jan 2018

Development Of Models And Solution Methods For Different Drayage Applications, Samaneh Shiri

Theses and Dissertations

In the last decades, intermodal freight transport is becoming more attractive in the global supply chains and freight transport policy makings. Intermodal freight transport provides a cost-effective, reliable, and efficient movement of freight by utilizing the strengths of different transport modes. The initial and final segment of intermodal freight transport, performed by truck, is known as “drayage.” The scheduling of truck movements in drayage operation within the service area of an intermodal terminal is an operational problem which leads to a truck scheduling problem that determines the efficient schedule of trucks while satisfying all transportation demands and constraints. Drayage accounts …


Nondestructive Evaluation Of Corrosion Damage In Reinforced Concrete Aged Slab Specimen, Rawya Abdulsattar Abduljabbar Jan 2018

Nondestructive Evaluation Of Corrosion Damage In Reinforced Concrete Aged Slab Specimen, Rawya Abdulsattar Abduljabbar

Theses and Dissertations

The deterioration of concrete bridge decks presents a maintenance challenge for most transportation agencies and bridge owners. This problem increases during the freeze-thaw cycle. De-icing salts can accelerate the deterioration process. Corrosion of steel reinforcement in reinforced concrete structures is considered a dominant factor causing premature deterioration, especially those structures located in a coastal environment. The resulting corrosion product produced has several times the volume of steel, resulting in cracking of the concrete cover if the corrosion is significant. In this study, a bridge deck specimen was subjected to an artificial environment to accelerate the corrosion process. Prior to this …


Computations Of The Dynamic Fracture Of Plane Structures By The Extended Finite Element Method, Iman Asareh Jan 2018

Computations Of The Dynamic Fracture Of Plane Structures By The Extended Finite Element Method, Iman Asareh

Theses and Dissertations

Finite element methods for the simulation of dynamic fracture in plane structures are presented. The method is a modified extended finite element method (XFEM) for dynamic fracture simulations with a new methodology to construct the XFEM basis functions for discontinuities. In contrast to conventional XFEM in which the extended interpolation is defined to only capture the discontinuities, the proposed method describes the enrichment functions so that they reproduce both the discontinuities and the polynomial bases of sufficiently high order which are critical for finite element convergence. Such enrichment functions, by adopting the Duffy’s transformation, can be simply defined in terms …