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Full-Text Articles in Engineering

Systems Approaches To Transdisciplinary Sustainable Development Issues, David Lawrence Zelinka Jan 2019

Systems Approaches To Transdisciplinary Sustainable Development Issues, David Lawrence Zelinka

Civil Engineering Graduate Theses & Dissertations

The goals of this dissertation are twofold. The first is to advance the discipline of sustainability science through the application of systems-based tools (primarily system dynamics) and civil engineering principles. Sustainability science is fundamental to implementing effective strategies for progressing sustainable development and improving human well-being around the planet, but it is still not fully developed as a science and needs new methods and approaches due to the field’s inherent interdisciplinarity and complexity. Civil engineering as a foundation provides mathematical knowledge, computer modeling skills, and a wide breadth of technical understanding, but it lacks the societal, political, and economic ...


Studies Of Earthquake Pounding Risk And Of Above-Code Seismic Design, Moad Isteita Jan 2019

Studies Of Earthquake Pounding Risk And Of Above-Code Seismic Design, Moad Isteita

Civil Engineering Graduate Theses & Dissertations

This thesis tests three hypotheses: (1) Some US practice to determine the required separation distance to preclude pounding between neighboring buildings is overly conservative. (2) Pounding between buildings with aligned floors significantly contributes to collapse. (3) Above-code design of a common engineered commercial building type is cost effective in many though perhaps not all US locations, at least from a benefit-cost-analysis perspective.

The first part of this thesis reexamines the required minimum permissible space between two adjacent buildings to preclude earthquake pounding. This part of the thesis employs and compares three analytical approaches to estimate the minimum safe distance conditioned ...


Sustainable Sanitation Systems: Understanding Priorities, Processes, And Pathways To Success, Allison Davis Jan 2019

Sustainable Sanitation Systems: Understanding Priorities, Processes, And Pathways To Success, Allison Davis

Civil Engineering Graduate Theses & Dissertations

Despite the unprecedented time, attention, and finances dedicated to increasing global access to sanitation, sanitation systems continue to fail at unacceptably high rates. Sanitation failure is a global concern, especially due to diminished public and environmental health and heightened economic costs. A commonly cited reason for sanitation failure is the selection of inappropriate technologies that do not address local priorities. To further evaluate this possible reason for failure, this dissertation employed a multi-method approach in 20 resource-limited communities in southern India with small-scale sanitation systems. Since sanitation priorities are mostly unknown, this research first focused on how to best identify ...


Performance Of Inelastic Structures On Mitigated And Unmitigated Liquefiable Soils: Evaluation Of Numerical Simulations With Centrifuge Tests, Jenny Zulay Ramirez Calderon Jan 2019

Performance Of Inelastic Structures On Mitigated And Unmitigated Liquefiable Soils: Evaluation Of Numerical Simulations With Centrifuge Tests, Jenny Zulay Ramirez Calderon

Civil Engineering Graduate Theses & Dissertations

A series of dynamic centrifuge experiments involving soil-foundation-mitigation-structure (SFMS) interaction on liquefiable soils are used to evaluate the ability of state-of-the-art numerical modeling in reliably predicting system performance (e.g., in terms of foundation settlement, rotation, roof accelerations, and column strains). This research comprises of two major components: (1) calibration and validation of two soil constitutive models with a series of fully drained and undrained, monotonic and cyclic, triaxial tests as well as a free-field centrifuge test on a layered, liquefiable soil deposit (without a building or a mitigation technique); and (2) numerical simulation of centrifuge tests that include multi-degree-of-freedom ...


Leveraging Emotional Engagement Techniques And Adult Learning Principles To Transform Safety Training, Siddharth Bhandari Jan 2019

Leveraging Emotional Engagement Techniques And Adult Learning Principles To Transform Safety Training, Siddharth Bhandari

Civil Engineering Graduate Theses & Dissertations

Safety training despite being the key measure to keeping workers safe within any occupational environment has not kept pace with the significant advancement in the fields of behavioral psychology and education. As a result, researchers have found that the pre-dated safety training techniques on construction sites fail in communicating information in a way that promotes long-term retention of knowledge among adult learners and they also end up generating a negative attitude towards safety among workers. Understanding the psychological antecedents to risk-taking behavior and utilizing prominent adult learning theories to revolutionize safety training could allow academics and practitioners to improve workers ...


Challenges With Sampling And Understanding Lead Corrosion Issues In Puerto Rico After Hurricane Maria, Melanie Rose Warren Jan 2019

Challenges With Sampling And Understanding Lead Corrosion Issues In Puerto Rico After Hurricane Maria, Melanie Rose Warren

Civil Engineering Graduate Theses & Dissertations

In January of 2018, an NSF RAPID project was launched to analyze the water quality in Puerto Rico after Hurricane Maria. More than 40 local drinking water taps were sampled over three sampling campaigns. This reconnaissance systematically included a collection of samples from publicly owned treatment systems (PRASA), privately owned systems operated by communities (non-PRASA), and unmonitored surface spring sources. The first sampling campaign was targeted towards gaining a holistic perspective of the water quality (e.g., bulk water quality parameters, nutrients, major ions, pathogens, DNA, disinfection byproducts (DBPs), and metals concentrations). However, elevated water lead levels in those initial ...


Predicting Construction Safety Performance, Wael Muqhim Alruqi Jan 2019

Predicting Construction Safety Performance, Wael Muqhim Alruqi

Civil Engineering Graduate Theses & Dissertations

Researchers and leading industry practitioners have turned to proactive safety metrics, such as safety leading indicators and safety climate, as predictors of future safety performance. Current academic research shows that the relationships between safety leading indicators and safety lagging indicators remain inconsistent, as well as the relationships between the dimensions of safety climate and safety performance. In addition, prior studies have measured the predictive capacity of these constructs separately even though they are logically associated with one another. Standardizing the measurement of proactive safety metrics and understanding how they relate to one another may facilitate consistency among the indicators or ...


How Much Does Stream-Groundwater Exchange Influence Whole-Stream Metabolism In A Small Mountain Stream?, Erin Elizabeth Jenkins Jan 2019

How Much Does Stream-Groundwater Exchange Influence Whole-Stream Metabolism In A Small Mountain Stream?, Erin Elizabeth Jenkins

Civil Engineering Graduate Theses & Dissertations

The open-channel oxygen method quantifies rates of gross primary productivity (GPP) and ecosystem respiration (ER) by employing the diel dissolved oxygen (DO) curve. This attributes stream metabolism to four processes: photosynthesis, oxidative respiration, reaeration, and groundwater flux. Groundwater flux, however, is often assumed to be negligible, which may introduce bias in estimates of metabolism. To investigate this, whole-stream metabolism and groundwater flux were measured in Como Creek, Colorado during the summer of 2018. Results from the BASE (Bayesian Single-station Estimation) metabolism model indicate that periods of anoxic groundwater input result in an overestimation of ER in baseline simulations. These data ...


A Data-Driven Toolchain For The Operational Performance Analysis And Optimization Of Buildings, Anthony Reed Florita Jan 2019

A Data-Driven Toolchain For The Operational Performance Analysis And Optimization Of Buildings, Anthony Reed Florita

Civil Engineering Graduate Theses & Dissertations

Automation has proven indispensable to advancing human endeavors. Within the built environment its evolution and sophistication are on the cusp of moving beyond automatic control into automated prediction and diagnosis. A data-driven toolchain is developed so human efforts can be focused on high-value concerns. The research examines smart buildings as a cyberphysical construct and places the Bayesian perspective as paramount. Prior knowledge is leveraged through common building energy modeling and simulation tools, which are utilized and extended. An iterative, three-step process is developed to 1) classify building energy performance scenarios, 2) forecast dynamics over a planning horizon of interest, and ...


Quantifying The Onset Of Damage For Light Frame Wood Buildings In Induced Earthquakes, Bridger William Baird Jan 2019

Quantifying The Onset Of Damage For Light Frame Wood Buildings In Induced Earthquakes, Bridger William Baird

Civil Engineering Graduate Theses & Dissertations

Since 2009, the frequency of (moment) magnitude (M) 3.0 earthquakes and larger in the Central United States, and especially Oklahoma, has risen from an average of 2 per year, to 200-700 per year. This increase in seismicity is a result of the deep injection of large quantities of wastewater from oil and gas activities underground.

In this study, damage to built infrastructure from induced earthquakes is investigated through nonlinear dynamic analysis and probabilistic damage assessment for light-frame wood structures common in Oklahoma. Specifically, we focus here on investigating the smallest magnitude of injection-induced earthquake that may cause damage to ...


Strong Form Meshfree Collocation Method For Higher Order And Nonlinear Pdes In Engineering Applications, Andrew Christian Beel Jan 2019

Strong Form Meshfree Collocation Method For Higher Order And Nonlinear Pdes In Engineering Applications, Andrew Christian Beel

Civil Engineering Graduate Theses & Dissertations

The strong form meshfree collocation method based on Taylor approximation and moving least squares is an alternative to finite element methods for solving partial differential equations in engineering applications. This study examines how the proposed alternative method solves (i) higher-order and (ii) nonlinear partial differential equations. First, the proposed method is formulated in Chapter 2 for the general discretization and solution of strong forms of partial differential equations. Chapter 3 presents the convergence and error behavior of the proposed method for the fourth-order Stommel-Munk equation for wind-driven ocean circulation, as well as the numerical solution of this equation on a ...


Evaluation Of A Heating Stove Changeout Program In The Navajo Nation: Pilot Study, Naomi Y. Chang Jan 2019

Evaluation Of A Heating Stove Changeout Program In The Navajo Nation: Pilot Study, Naomi Y. Chang

Civil Engineering Graduate Theses & Dissertations

Many homes on the Navajo Nation rely on wood and coal in old, inefficient heating stoves. An EPA-certified Navajo Hybrid Stove that can burn both wood and coal, was distributed to homes in the Navajo Nation. Collocation experiments were conducted to determine agreement among the DustTrak units and QTrak units. The correction factors and correlations for units of the same instrument were close to one; therefore, no adjustment to the data was necessary. A wood/coal smoke correction factor (W/CSCF) of 2.60 that is representative of wood/coal smoke exposure in Navajo homes was also determined for the ...


Effects Of Ozonation During Ceramic Microfiltration Of Water Containing Natural Organic Matter, Evan Martin Owen Jan 2019

Effects Of Ozonation During Ceramic Microfiltration Of Water Containing Natural Organic Matter, Evan Martin Owen

Civil Engineering Graduate Theses & Dissertations

The application of low-pressure membrane filtration such as microfiltration (MF) and ultrafiltration (UF) have become progressively well-established in the drinking and wastewater technology industry over the past few decades. While polymeric membranes dominate this sector of the water industry, ceramic membranes have become an increasingly popular and advantageous alternative to polymeric materials. Most importantly, ceramic membranes can be effectively employed to treat high-fouling impaired quality source water because of the inherent material robustness, that can withstand in-situ oxidative cleaning regimes.

Given the ozone (O3)-resistant nature of ceramic membranes, this research demonstrated that preozonation plays a crucial role in both ...


Properties Of Nevada Sand Under Monotonic, Sinusoidal, And Irregular Loading, David Allen Provost Jan 2019

Properties Of Nevada Sand Under Monotonic, Sinusoidal, And Irregular Loading, David Allen Provost

Civil Engineering Graduate Theses & Dissertations

This study involved an investigation into the properties of Nevada sand under monotonic, cyclic sinusoidal, and irregular cyclic loading. The study also was used to determine the capabilities of the new Wille Geotechnik triaxial press that was purchased for use at the University of Colorado Boulder. The properties of Nevada sand are important to understand for the ongoing seismic research being conducted at CU Boulder, specifically for the calibration of numerical models to simulate the results of centrifuge testing. There had been previous work completed by others to define the monotonic and cyclic sinusoidal response of the soil, but the ...


Diagnosing Drivers Of Reservoir Sedimentation In The Western Us: A Case Study Of Prineville Reservoir, Oregon, Leah Clare Bensching Jan 2019

Diagnosing Drivers Of Reservoir Sedimentation In The Western Us: A Case Study Of Prineville Reservoir, Oregon, Leah Clare Bensching

Civil Engineering Graduate Theses & Dissertations

There is great need to quantify reservoir storage loss due to sediment. Less than 1% of reservoirs in the US have more than one volume survey. Due to the lack of frequent data collection, a constant rate sediment yield from year to year is often assumed. This study aims to explore the following questions: 1) Can hydrologically-forced sediment algorithms help us advance reservoir sedimentation estimates to improve future planning? 2) To which processes and inputs are reservoir sedimentation estimates most sensitive? 3) What can we learn from models that the linear sediment accumulation assumption fails to assess? It will address ...


Water Quality Of Groundwater In Six Counties In Western Colorado: Evaluating Drinking Water Hazards And Developing Public Tools To Disseminate Well Information, Holly Ann Miller Jan 2019

Water Quality Of Groundwater In Six Counties In Western Colorado: Evaluating Drinking Water Hazards And Developing Public Tools To Disseminate Well Information, Holly Ann Miller

Civil Engineering Graduate Theses & Dissertations

Many residents in six counties on Colorado's Western Slope rely on privately owned groundwater wells as their primary source of drinking water. Because the water quality from these privately-owned wells is unregulated, these wells are often untested, which constitutes a risk to public health. To identify and address the risks to well owners, the West Central Public Health Partnership (WCPHP), recruited homeowners to sample and submit their well water for analyses. The WCPHP requested assistance and expertise to evaluate the hazards of drinking groundwater, and to develop ways to visualize the hazards to educate the public.

Well locations and ...


Radon In Colorado Springs, Co: Measuring And Modeling Before And After Weatherization Of Low-Income Homes, Tess Bloom Jan 2019

Radon In Colorado Springs, Co: Measuring And Modeling Before And After Weatherization Of Low-Income Homes, Tess Bloom

Civil Engineering Graduate Theses & Dissertations

The following thesis details an examination of radon and indoor environmental quality for low-income homes in Colorado Spring, Colorado. This investigation was completed in two parts: a field study and a modeling study. The main aim was to draw conclusions on the connection between weatherization and indoor radon concentration. Additionally, fine particulate matter (PM2.5), total volatile organic compounds (TVOCs), and mold and moisture were investigated before and after weatherization. From the field study, it was determined that there is no connection between weatherization and radon, PM2.5, TVOCs, and mold and moisture. Radon concentrations appears to vary ...


Informing Many-Objective Decision-Making For Water Rights Allocations And Trading Dynamics Conditioned On A Streamflow Prediction Regime In The Elqui River Basin, Melissa A. Estep Jan 2019

Informing Many-Objective Decision-Making For Water Rights Allocations And Trading Dynamics Conditioned On A Streamflow Prediction Regime In The Elqui River Basin, Melissa A. Estep

Civil Engineering Graduate Theses & Dissertations

The Elqui Valley in northern Chile faces increasing water stress due to a growing agricultural sector. This study evaluates how improvements in season-ahead forecasting skill and changes in water rights trading dynamics impact the ability for seasonal reservoir management to meet the water needs of various actors in the basin. By establishing a baseline forecast of perfect foresight of observed streamflow data, the analysis evaluates how the use of an updated forecasting technique compares to climatology in its ability to meet management needs. Using the RiverWare river system modeling tool, multiple scenarios representing different suites of trade and reservoir operating ...


Hydraulic Fracturing Fluid Additives: Method For Detection With Mass Spectrometry, New Identifications, And Utility Of Biological Treatment, Kurban Andrew Sitterley Jan 2019

Hydraulic Fracturing Fluid Additives: Method For Detection With Mass Spectrometry, New Identifications, And Utility Of Biological Treatment, Kurban Andrew Sitterley

Civil Engineering Graduate Theses & Dissertations

Hydraulic fracturing simultaneously uses and generates billions of gallons of water every year that must be sourced and managed. Fracturing fluid chemicals, including many ethoxylated and propoxylated surfactants, are added to water to make fracturing fluid. Flowback and produced water, the primary contributors to the waste stream, are generated during the drilling operations and throughout the life of the well.

Inherent to developing a management approach is adequate methods of characterization and treatment for dissolved components. This research presents the development of a solid phase extraction method for identifying and detecting common fluid additives with mass spectrometry (MS). With this ...


Mechanical And Durability Properties Of Concrete Under Low Temperatures, Yao Wang Jan 2019

Mechanical And Durability Properties Of Concrete Under Low Temperatures, Yao Wang

Civil Engineering Graduate Theses & Dissertations

Frost attack can heavily damage concrete materials and concrete structures. Therefore, it is important to predict the service life of concrete structures considering the effect of the deterioration process. A theoretical model based on Mori-Tanaka micromechanics method was developed to estimate the deterioration of elastic properties of concrete under low temperatures. The model took into account a continuous pore size distribution for cement paste, freezing temperatures with different pore sizes, and damage development in cement paste. The model was able to characterize the stiffening effect due to the formation of solid ice and the weakening effect of the damage development ...


Centrifuge Modeling Of Dense Granular Columns In Layered Liquefiable Soils With Varying Stratigraphy And Overlying Structures, Mahir A. Badanagki Jan 2019

Centrifuge Modeling Of Dense Granular Columns In Layered Liquefiable Soils With Varying Stratigraphy And Overlying Structures, Mahir A. Badanagki

Civil Engineering Graduate Theses & Dissertations

Soil liquefaction and ground failure have been a major source of damage to slopes, embankments, and structures during previous earthquakes. The risk of liquefaction and associated ground deformations can be reduced by various forms of improvement, including the granular column technique. Granular columns are known to be cost effective and environmentally friendly, and they have been in use since the 1970’s to mitigate the liquefaction hazard. Granular columns mitigate the consequences of soil liquefaction through a combination of: 1) installation-induced ground densification, 2) increase in lateral effective stresses in the surrounding soil, 3) increase in shear stiffness, and 4 ...